MAX6318LHUK40BZ中文资料
MAX13085EESA-T中文资料
General DescriptionThe MAX13080E–MAX13089E +5.0V, ±15kV ESD-protect-ed, RS-485/RS-422 transceivers feature one driver and one receiver. These devices include fail-safe circuitry,guaranteeing a logic-high receiver output when receiver inputs are open or shorted. The receiver outputs a logic-high if all transmitters on a terminated bus are disabled (high impedance). The MAX13080E–MAX13089E include a hot-swap capability to eliminate false transitions on the bus during power-up or hot insertion.The MAX13080E/MAX13081E/MAX13082E feature reduced slew-rate drivers that minimize EMI and reduce reflections caused by improperly terminated cables, allowing error-free data transmission up to 250kbps. The MAX13083E/MAX13084E/MAX13085E also feature slew-rate-limited drivers but allow transmit speeds up to 500kbps. The MAX13086E/MAX13087E/MAX13088E driver slew rates are not limited, making transmit speeds up to 16Mbps possible. The MAX13089E slew rate is pin selectable for 250kbps,500kbps, and 16Mbps.The MAX13082E/MAX13085E/MAX13088E are intended for half-duplex communications, and the MAX13080E/MAX13081E/MAX13083E/MAX13084E/MAX13086E/MAX13087E are intended for full-duplex communica-tions. The MAX13089E is selectable for half-duplex or full-duplex operation. It also features independently programmable receiver and transmitter output phase through separate pins.The MAX13080E–MAX13089E transceivers draw 1.2mA of supply current when unloaded or when fully loaded with the drivers disabled. All devices have a 1/8-unit load receiver input impedance, allowing up to 256transceivers on the bus.The MAX13080E/MAX13083E/MAX13086E/MAX13089E are available in 14-pin PDIP and 14-pin SO packages.The MAX13081E/MAX13082E/MAX13084E/MAX13085E/MAX13087E/MAX13088E are available in 8-pin PDIP and 8-pin SO packages. The devices operate over the com-mercial, extended, and automotive temperature ranges.ApplicationsUtility Meters Lighting Systems Industrial Control Telecom Security Systems Instrumentation ProfibusFeatures♦+5.0V Operation♦Extended ESD Protection for RS-485/RS-422 I/O Pins±15kV Human Body Model ♦True Fail-Safe Receiver While Maintaining EIA/TIA-485 Compatibility ♦Hot-Swap Input Structures on DE and RE ♦Enhanced Slew-Rate Limiting Facilitates Error-Free Data Transmission(MAX13080E–MAX13085E/MAX13089E)♦Low-Current Shutdown Mode (Except MAX13081E/MAX13084E/MAX13087E)♦Pin-Selectable Full-/Half-Duplex Operation (MAX13089E)♦Phase Controls to Correct for Twisted-Pair Reversal (MAX13089E)♦Allow Up to 256 Transceivers on the Bus ♦Available in Industry-Standard 8-Pin SO PackageMAX13080E–MAX13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers________________________________________________________________Maxim Integrated Products 1Ordering Information19-3590; Rev 1; 4/05For pricing, delivery, and ordering information,please contact Maxim/Dallas Direct!at 1-888-629-4642, or visit Maxim’s website at .Selector Guide, Pin Configurations, and Typical Operating Circuits appear at end of data sheet.Ordering Information continued at end of data sheet.M A X 13080E –M A X 13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers 2_______________________________________________________________________________________ABSOLUTE MAXIMUM RATINGSDC ELECTRICAL CHARACTERISTICS(V CC = +5.0V ±10%, T A = T MIN to T MAX , unless otherwise noted. Typical values are at V CC = +5.0V and T A = +25°C.) (Note 1)Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.(All Voltages Referenced to GND)Supply Voltage (V CC ).............................................................+6V Control Input Voltage (RE , DE, SLR,H/F , TXP, RXP)......................................................-0.3V to +6V Driver Input Voltage (DI)...........................................-0.3V to +6V Driver Output Voltage (Z, Y, A, B).............................-8V to +13V Receiver Input Voltage (A, B)....................................-8V to +13V Receiver Input VoltageFull Duplex (A, B)..................................................-8V to +13V Receiver Output Voltage (RO)....................-0.3V to (V CC + 0.3V)Driver Output Current.....................................................±250mAContinuous Power Dissipation (T A = +70°C)8-Pin SO (derate 5.88mW/°C above +70°C).................471mW 8-Pin Plastic DIP (derate 9.09mW/°C above +70°C).....727mW 14-Pin SO (derate 8.33mW/°C above +70°C)...............667mW 14-Pin Plastic DIP (derate 10.0mW/°C above +70°C)...800mW Operating Temperature RangesMAX1308_EC_ _.................................................0°C to +75°C MAX1308_EE_ _..............................................-40°C to +85°C MAX1308_EA_ _............................................-40°C to +125°C Junction Temperature......................................................+150°C Storage Temperature Range.............................-65°C to +150°C Lead Temperature (soldering, 10s).................................+300°CMAX13080E–MAX13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers_______________________________________________________________________________________3DC ELECTRICAL CHARACTERISTICS (continued)(V CC = +5.0V ±10%, T A = T MIN to T MAX , unless otherwise noted. Typical values are at V CC = +5.0V and T A = +25°C.) (Note 1)M A X 13080E –M A X 13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers 4_______________________________________________________________________________________DRIVER SWITCHING CHARACTERISTICSMAX13080E/MAX13081E/MAX13082E/MAX13089E WITH SRL = UNCONNECTED (250kbps)(V CC = +5.0V ±10%, T A = T MIN to T MAX , unless otherwise noted. Typical values are at V CC = +5.0V and T A = +25°C.)RECEIVER SWITCHING CHARACTERISTICSMAX13080E/MAX13081E/MAX13082E/MAX13089E WITH SRL = UNCONNECTED (250kbps)(V CC = +5.0V ±10%, T A = T MIN to T MAX , unless otherwise noted. Typical values are at V CC = +5.0V and T A = +25°C.)MAX13080E–MAX13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers_______________________________________________________________________________________5DRIVER SWITCHING CHARACTERISTICSMAX13083E/MAX13084E/MAX13085E/MAX13089E WITH SRL = V CC (500kbps)(V CC = +5.0V ±10%, T A = T MIN to T MAX , unless otherwise noted. Typical values are at V CC = +5.0V and T A = +25°C.)RECEIVER SWITCHING CHARACTERISTICSMAX13083E/MAX13084E/MAX13085E/MAX13089E WITH SRL = V CC (500kbps)(V CC = +5.0V ±10%, T A = T MIN to T MAX , unless otherwise noted. Typical values are at V CC = +5.0V and T A = +25°C.)M A X 13080E –M A X 13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers 6_______________________________________________________________________________________DRIVER SWITCHING CHARACTERISTICSMAX13086E/MAX13087E/MAX13088E/MAX13089E WITH SRL = GND (16Mbps)(V CC = +5.0V ±10%, T A = T MIN to T MAX , unless otherwise noted. Typical values are at V CC = +5.0V and T A = +25°C.)RECEIVER SWITCHING CHARACTERISTICSMAX13086E/MAX13087E/MAX13088E/MAX13089E WITH SRL = GND (16Mbps)(V CC = +5.0V ±10%, T A = T MIN to T MAX , unless otherwise noted. Typical values are at V CC = +5.0V and T A = +25°C.)Note 2:∆V OD and ∆V OC are the changes in V OD and V OC , respectively, when the DI input changes state.Note 3:The short-circuit output current applies to peak current just prior to foldback current limiting. The short-circuit foldback outputcurrent applies during current limiting to allow a recovery from bus contention.MAX13080E–MAX13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers_______________________________________________________________________________________70.800.901.501.101.001.201.301.401.60-40-10520-253550958011065125SUPPLY CURRENT vs. TEMPERATURETEMPERATURE (°C)S U P P L Y C U R R E N T (m A )0201040305060021345OUTPUT CURRENTvs. RECEIVER OUTPUT-HIGH VOLTAGEM A X 13080E -89E t o c 02OUTPUT HIGH VOLTAGE (V)O U T P U T C U R R E N T (m A )20104030605070021345OUTPUT CURRENTvs. RECEIVER OUTPUT-LOW VOLTAGEM A X 13080E -89E t o c 03OUTPUT LOW VOLTAGE (V)O U T P U T C U R R E N T (m A )4.04.44.24.84.65.25.05.4RECEIVER OUTPUT-HIGH VOLTAGEvs. TEMPERATURETEMPERATURE (°C)O U T P U T H I G H V O L T A G E (V )-40-10520-2535509580110651250.10.70.30.20.40.50.60.8RECEIVER OUTPUT-LOW VOLTAGEvs. TEMPERATURETEMPERATURE (°C)O U T P U T L O W V O L T A G E (V )-40-10520-25355095801106512502040608010012014016012345DRIVER DIFFERENTIAL OUTPUT CURRENT vs. DIFFERENTIAL OUTPUT VOLTAGEDIFFERENTIAL OUTPUT VOLTAGE (V)D I F FE R E N T I A L O U T P U T C U R R E N T (m A )2.02.82.43.63.24.44.04.8DRIVER DIFFERENTIAL OUTPUT VOLTAGE vs. TEMPERATURED I F FE R E N T I A L O U T P U T V O L T A G E (V )-40-10520-253550958011065125TEMPERATURE (°C)40201008060120140180160200-7-5-4-6-3-2-1012354OUTPUT CURRENT vs. TRANSMITTEROUTPUT-HIGH VOLTAGEOUTPUT HIGH VOLTAGE (V)O U T P U T C U R R E N T (m A )60402080100120140160180200042681012OUTPUT CURRENT vs. TRANSMITTEROUTPUT-LOW VOLTAGEOUTPUT-LOW VOLTAGE (V)O U T P U T C U R R E N T (m A )Typical Operating Characteristics(V CC = +5.0V, T A = +25°C, unless otherwise noted.)M A X 13080E –M A X 13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers 8_______________________________________________________________________________________21543679810SHUTDOWN CURRENT vs. TEMPERATUREM A X 13080E -89E t o c 10S H U T D O W N C U R R E N T (µA )-40-10520-253550958011065125TEMPERATURE (°C)600800700100090011001200DRIVER PROPAGATION DELAY vs. TEMPERATURE (250kbps)D R I VE R P R O P A G A T I O N D E L A Y (n s )-40-10520-253550958011065125TEMPERATURE (°C)300400350500450550600DRIVER PROPAGATION DELAY vs. TEMPERATURE (500kbps)D R I VE R P R O P A G A T I O N D E L A Y (n s )-40-10520-253550958011065125TEMPERATURE (°C)1070302040506080DRIVER PROPAGATION DELAY vs. TEMPERATURE (16Mbps)D R I VE R P R O P A G A T I O N D E L A Y (n s )-40-10520-253550958011065125TEMPERATURE (°C)40201008060120140160180RECEIVER PROPAGATION DELAYvs. TEMPERATURE (250kpbs AND 500kbps)R E C E I V E R P R O P A G A T I O N D E L A Y (n s )-40-10520-253550958011065125TEMPERATURE (°C)40201008060120140160180RECEIVER PROPAGATION DELAYvs. TEMPERATURE (16Mbps)R EC E I V E R P R O P A G AT I O N D E L A Y (n s )-40-10520-253550958011065125TEMPERATURE (°C)2µs/div DRIVER PROPAGATION DELAY (250kbps)DI 2V/divV Y - V Z 5V/divR L = 100Ω200ns/divRECEIVER PROPAGATION DELAY(250kbps AND 500kbps)V A - V B 5V/divRO 2V/divTypical Operating Characteristics (continued)(V CC = +5.0V, T A = +25°C, unless otherwise noted.)MAX13080E–MAX13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers_______________________________________________________________________________________9Test Circuits and Waveforms400ns/divDRIVER PROPAGATION DELAY (500kbps)DI 2V/divR L = 100ΩV Y - V Z 5V/div10ns/div DRIVER PROPAGATION DELAY (16Mbps)DI 2V/divR L = 100ΩV Y 2V/divV Z 2V/div40ns/divRECEIVER PROPAGATION DELAY (16Mbps)V B 2V/divR L = 100ΩRO 2V/divV A 2V/divTypical Operating Characteristics (continued)(V CC = +5.0V, T A = +25°C, unless otherwise noted.)Figure 2. Driver Timing Test CircuitM A X 13080E –M A X 13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers 10______________________________________________________________________________________Test Circuits and Waveforms (continued)Figure 4. Driver Enable and Disable Times (t DHZ , t DZH , t DZH(SHDN))DZL DLZ DLZ(SHDN)MAX13080E–MAX13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 TransceiversTest Circuits and Waveforms (continued)Figure 6. Receiver Propagation Delay Test CircuitM A X 13080E –M A X 13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 TransceiversMAX13080E–MAX13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 TransceiversMAX13080E/MAX13083E/MAX13086EMAX13081E/MAX13084E/MAX13086E/MAX13087EFunction TablesM A X 13080E –M A X 13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers MAX13082E/MAX13085E/MAX13088EFunction Tables (continued)MAX13089EDetailed Description The MAX13080E–MAX13089E high-speed transceivers for RS-485/RS-422 communication contain one driver and one receiver. These devices feature fail-safe circuit-ry, which guarantees a logic-high receiver output when the receiver inputs are open or shorted, or when they are connected to a terminated transmission line with all dri-vers disabled (see the Fail-Safe section). The MAX13080E/MAX13082E/MAX13083E/MAX13085E/ MAX13086E/MAX13088E/MAX13089E also feature a hot-swap capability allowing line insertion without erroneous data transfer (see the Hot Swap Capability section). The MAX13080E/MAX13081E/MAX13082E feature reduced slew-rate drivers that minimize EMI and reduce reflec-tions caused by improperly terminated cables, allowing error-free data transmission up to 250kbps. The MAX13083E/MAX13084E/MAX13085E also offer slew-rate limits allowing transmit speeds up to 500kbps. The MAX13086E/MAX13087E/MAX13088Es’ driver slew rates are not limited, making transmit speeds up to 16Mbps possible. The MAX13089E’s slew rate is selectable between 250kbps, 500kbps, and 16Mbps by driving a selector pin with a three-state driver.The MAX13082E/MAX13085E/MAX13088E are half-duplex transceivers, while the MAX13080E/MAX13081E/ MAX13083E/MAX13084E/MAX13086E/MAX13087E are full-duplex transceivers. The MAX13089E is selectable between half- and full-duplex communication by driving a selector pin (H/F) high or low, respectively.All devices operate from a single +5.0V supply. Drivers are output short-circuit current limited. Thermal-shutdown circuitry protects drivers against excessive power dissi-pation. When activated, the thermal-shutdown circuitry places the driver outputs into a high-impedance state.Receiver Input Filtering The receivers of the MAX13080E–MAX13085E, and the MAX13089E when operating in 250kbps or 500kbps mode, incorporate input filtering in addition to input hysteresis. This filtering enhances noise immunity with differential signals that have very slow rise and fall times. Receiver propagation delay increases by 25% due to this filtering.Fail-Safe The MAX13080E family guarantees a logic-high receiver output when the receiver inputs are shorted or open, or when they are connected to a terminated transmission line with all drivers disabled. This is done by setting the receiver input threshold between -50mV and -200mV. If the differential receiver input voltage (A - B) is greater than or equal to -50mV, RO is logic-high. If (A - B) is less than or equal to -200mV, RO is logic-low. In the case of a terminated bus with all transmitters disabled, the receiv-er’s differential input voltage is pulled to 0V by the termi-nation. With the receiver thresholds of the MAX13080E family, this results in a logic-high with a 50mV minimumnoise margin. Unlike previous fail-safe devices, the-50mV to -200mV threshold complies with the ±200mVEIA/TIA-485 standard.Hot-Swap Capability (Except MAX13081E/MAX13084E/MAX13087E)Hot-Swap InputsWhen circuit boards are inserted into a hot or powered backplane, differential disturbances to the data buscan lead to data errors. Upon initial circuit board inser-tion, the data communication processor undergoes itsown power-up sequence. During this period, the processor’s logic-output drivers are high impedanceand are unable to drive the DE and RE inputs of these devices to a defined logic level. Leakage currents up to±10µA from the high-impedance state of the proces-sor’s logic drivers could cause standard CMOS enableinputs of a transceiver to drift to an incorrect logic level. Additionally, parasitic circuit board capacitance couldcause coupling of V CC or GND to the enable inputs. Without the hot-swap capability, these factors could improperly enable the transceiver’s driver or receiver.When V CC rises, an internal pulldown circuit holds DElow and RE high. After the initial power-up sequence,the pulldown circuit becomes transparent, resetting thehot-swap tolerable input.Hot-Swap Input CircuitryThe enable inputs feature hot-swap capability. At theinput there are two NMOS devices, M1 and M2 (Figure 9). When V CC ramps from zero, an internal 7µstimer turns on M2 and sets the SR latch, which alsoturns on M1. Transistors M2, a 1.5mA current sink, andM1, a 500µA current sink, pull DE to GND through a5kΩresistor. M2 is designed to pull DE to the disabledstate against an external parasitic capacitance up to100pF that can drive DE high. After 7µs, the timer deactivates M2 while M1 remains on, holding DE low against three-state leakages that can drive DE high. M1 remains on until an external source overcomes the required input current. At this time, the SR latch resetsand M1 turns off. When M1 turns off, DE reverts to a standard, high-impedance CMOS input. Whenever V CCdrops below 1V, the hot-swap input is reset.For RE there is a complementary circuit employing two PMOS devices pulling RE to V CC. MAX13080E–MAX13089E+5.0V, ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 TransceiversM A X 13080E –M A X 13089EMAX13089E ProgrammingThe MAX13089E has several programmable operating modes. Transmitter rise and fall times are programma-ble, resulting in maximum data rates of 250kbps,500kbps, and 16Mbps. To select the desired data rate,drive SRL to one of three possible states by using a three-state driver: V CC , GND, or unconnected. F or 250kbps operation, set the three-state device in high-impedance mode or leave SRL unconnected. F or 500kbps operation, drive SRL high or connect it to V CC .F or 16Mbps operation, drive SRL low or connect it to GND. SRL can be changed during operation without interrupting data communications.Occasionally, twisted-pair lines are connected backward from normal orientation. The MAX13089E has two pins that invert the phase of the driver and the receiver to cor-rect this problem. F or normal operation, drive TXP and RXP low, connect them to ground, or leave them uncon-nected (internal pulldown). To invert the driver phase,drive TXP high or connect it to V CC . To invert the receiver phase, drive RXP high or connect it to V CC . Note that the receiver threshold is positive when RXP is high.The MAX13089E can operate in full- or half-duplex mode. Drive H/F low, leave it unconnected (internal pulldown), or connect it to GND for full-duplex opera-tion. Drive H/F high for half-duplex operation. In full-duplex mode, the pin configuration of the driver and receiver is the same as that of a MAX13080E. In half-duplex mode, the receiver inputs are internally connect-ed to the driver outputs through a resistor-divider. This effectively changes the function of the device’s outputs.Y becomes the noninverting driver output and receiver input, Z becomes the inverting driver output and receiver input. In half-duplex mode, A and B are still connected to ground through an internal resistor-divider but they are not internally connected to the receiver.±15kV ESD ProtectionAs with all Maxim devices, ESD-protection structures are incorporated on all pins to protect against electro-static discharges encountered during handling and assembly. The driver outputs and receiver inputs of the MAX13080E family of devices have extra protection against static electricity. Maxim’s engineers have devel-oped state-of-the-art structures to protect these pins against ESD of ±15kV without damage. The ESD struc-tures withstand high ESD in all states: normal operation,shutdown, and powered down. After an ESD event, the MAX13080E–MAX13089E keep working without latchup or damage.ESD protection can be tested in various ways. The transmitter outputs and receiver inputs of the MAX13080E–MAX13089E are characterized for protec-tion to the following limits:•±15kV using the Human Body Model•±6kV using the Contact Discharge method specified in IEC 61000-4-2ESD Test ConditionsESD performance depends on a variety of conditions.Contact Maxim for a reliability report that documents test setup, test methodology, and test results.Human Body ModelFigure 10a shows the Human Body Model, and Figure 10b shows the current waveform it generates when dis-charged into a low impedance. This model consists of a 100pF capacitor charged to the ESD voltage of interest,which is then discharged into the test device through a 1.5k Ωresistor.IEC 61000-4-2The IEC 61000-4-2 standard covers ESD testing and performance of finished equipment. However, it does not specifically refer to integrated circuits. The MAX13080E family of devices helps you design equip-ment to meet IEC 61000-4-2, without the need for addi-tional ESD-protection components.+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 TransceiversThe major difference between tests done using the Human Body Model and IEC 61000-4-2 is higher peak current in IEC 61000-4-2 because series resistance is lower in the IEC 61000-4-2 model. Hence, the ESD with-stand voltage measured to IEC 61000-4-2 is generally lower than that measured using the Human Body Model. Figure 10c shows the IEC 61000-4-2 model, and Figure 10d shows the current waveform for IEC 61000-4-2 ESD Contact Discharge test.Machine Model The machine model for ESD tests all pins using a 200pF storage capacitor and zero discharge resis-tance. The objective is to emulate the stress caused when I/O pins are contacted by handling equipment during test and assembly. Of course, all pins require this protection, not just RS-485 inputs and outputs.Applications Information256 Transceivers on the BusThe standard RS-485 receiver input impedance is 12kΩ(1-unit load), and the standard driver can drive up to 32-unit loads. The MAX13080E family of transceivers has a1/8-unit load receiver input impedance (96kΩ), allowingup to 256 transceivers to be connected in parallel on one communication line. Any combination of these devices,as well as other RS-485 transceivers with a total of 32-unit loads or fewer, can be connected to the line.Reduced EMI and ReflectionsThe MAX13080E/MAX13081E/MAX13082E feature reduced slew-rate drivers that minimize EMI and reduce reflections caused by improperly terminated cables, allowing error-free data transmission up to250kbps. The MAX13083E/MAX13084E/MAX13085Eoffer higher driver output slew-rate limits, allowing transmit speeds up to 500kbps. The MAX13089E withSRL = V CC or unconnected are slew-rate limited. WithSRL unconnected, the MAX13089E error-free data transmission is up to 250kbps. With SRL connected toV CC,the data transmit speeds up to 500kbps. MAX13080E–MAX13089E+5.0V, ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 TransceiversM A X 13080E –M A X 13089ELow-Power Shutdown Mode (Except MAX13081E/MAX13084E/MAX13087E)Low-power shutdown mode is initiated by bringing both RE high and DE low. In shutdown, the devices typically draw only 2.8µA of supply current.RE and DE can be driven simultaneously; the devices are guaranteed not to enter shutdown if RE is high and DE is low for less than 50ns. If the inputs are in this state for at least 700ns, the devices are guaranteed to enter shutdown.Enable times t ZH and t ZL (see the Switching Characteristics section) assume the devices were not in a low-power shutdown state. Enable times t ZH(SHDN)and t ZL(SHDN)assume the devices were in shutdown state. It takes drivers and receivers longer to become enabled from low-power shutdown mode (t ZH(SHDN), t ZL(SHDN))than from driver/receiver-disable mode (t ZH , t ZL ).Driver Output ProtectionTwo mechanisms prevent excessive output current and power dissipation caused by faults or by bus contention.The first, a foldback current limit on the output stage,provides immediate protection against short circuits over the whole common-mode voltage range (see the Typical Operating Characteristics ). The second, a thermal-shut-down circuit, forces the driver outputs into a high-imped-ance state if the die temperature exceeds +175°C (typ).Line LengthThe RS-485/RS-422 standard covers line lengths up to 4000ft. F or line lengths greater than 4000ft, use the repeater application shown in Figure 11.Typical ApplicationsThe MAX13082E/MAX13085E/MAX13088E/MAX13089E transceivers are designed for bidirectional data commu-nications on multipoint bus transmission lines. F igures 12 and 13 show typical network applications circuits. To minimize reflections, terminate the line at both ends in its characteristic impedance, and keep stub lengths off the main line as short as possible. The slew-rate-lim-ited MAX13082E/MAX13085E and the two modes of the MAX13089E are more tolerant of imperfect termination.Chip InformationTRANSISTOR COUNT: 1228PROCESS: BiCMOS+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 TransceiversFigure 11. Line Repeater for MAX13080E/MAX13081E/MAX13083E/MAX13084E/MAX13086E/MAX13087E/MAX13089E in Full-Duplex Mode+5.0V, ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 TransceiversMAX13080E–MAX13089EM A X 13080E –M A X 13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 TransceiversPin Configurations and Typical Operating CircuitsMAX13080E–MAX13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers______________________________________________________________________________________21Pin Configurations and Typical Operating Circuits (continued)M A X 13080E –M A X 13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers 22______________________________________________________________________________________Ordering Information (continued)MAX13080E–MAX13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers______________________________________________________________________________________23Package Information (continued)(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,go to /packages .)。
MAX3181EEUK-T资料
For free samples & the latest literature: , or phone 1-800-998-8800.For small orders, phone 1-800-835-8769.General DescriptionThe MAX3180E–MAX3183E single RS -232 receivers in a SOT23-5 package are designed for space- and cost-constrained applications requiring minimal RS -232communications. The receiver inputs are protected to ±15kV using IEC 1000-4-2 Air-Gap Discharge, to ±8kV using IEC 1000-4-2 Contact Discharge, and to ±15kV per the Human Body Model, ensuring compliance with international standards.The devices minimize power and heat dissipation by consuming only 0.5µA supply current from a +3.0V to +5.5V supply, and they guarantee true RS -232 perfor-mance up to a 1.5Mbps data rate. The MAX3180E/MAX3182E feature a three-state TTL/CMOS receiver output that is controlled by an EN logic input. The MAX3181E/MAX3183E feature an INVALID output that indicates valid RS-232 signals at the receiver input for applications requiring automatic system wake-up. The MAX3182E/MAX3183E have a noninverting output,while the MAX3180E/MAX3181E have a standard inverting output.ApplicationsFeatureso Tiny SOT23-5 Packageo ESD-Protected RS-232 Input±15kV—Human Body Model±8kV—IEC 1000-4-2, Contact Discharge ±15kV—IEC 1000-4-2, Air-Gap Discharge o 0.5µA Supply Currento 1.5Mbps Guaranteed Data Rateo Meets EIA/TIA-232 and V.28/V.24 Specifications Down to V CC = +3.0V o INVALID Output Indicates Valid RS-232 Signal at Receiver Input (MAX3181E/MAX3183E)o Three-State TTL/CMOS Receiver Output (MAX3180E/MAX3182E)o Noninverting RS-232 Output (MAX3182E/MAX3183E)MAX3180E–MAX3183E±15kV ESD-Protected, 0.5µA, +3V to +5.5V ,1.5Mbps RS-232 Receivers in SOT23-5________________________________________________________________Maxim Integrated Products 119-1479; Rev 1; 7/99Ordering InformationM A X 3180E –M A X 3183E±15kV ESD-Protected, 0.5µA, +3V to +5.5V ,1.5Mbps RS-232 Receivers in SOT23-52_______________________________________________________________________________________ABSOLUTE MAXIMUM RATINGSELECTRICAL CHARACTERISTICS(V CC = +3.0V to +5.5V, T A = T MIN to T MAX , unless otherwise noted. Typical values are at V CC = +5.0V, T A = +25°C.) (Note 1)Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.V CC to GND..............................................................-0.3V to +6V RIN to GND..........................................................................±25V EN , ROUT, INVALID to GND......................-0.3V to (V CC + 0.3V)Continuous Power Dissipation (T A = +70°C)SOT23-5 (derate 7.1mW/°C above +70°C)...................571mWOperating Temperature Range ...........................-40°C to +85°C Storage Temperature Range.............................-65°C to +150°C Lead Temperature (soldering, 10sec).............................+300°CMAX3180E–MAX3183E±15kV ESD-Protected, 0.5µA, +3V to +5.5V ,1.5Mbps RS-232 Receivers in SOT23-5_______________________________________________________________________________________3ELECTRICAL CHARACTERISTICS (continued)(V CC = +3.0V to +5.5V, T A = T MIN to T MAX , unless otherwise noted. Typical values are at V CC = +5.0V, T A = +25°C.) (Note 1)Typical Operating Characteristics(V CC = +5V, T A = +25°C, unless otherwise noted.)00.20.10.40.30.60.50.700.51.0 1.5SUPPLY CURRENT vs. DATA RATEDATA RATE (Mbps)S U P P L Y C U R R E N T (m A )2302702502903303103503.0 3.5 5.04.54.0 5.5RIN TO INVALID HIGH vs. SUPPLY VOLTAGEM A X 3180E -02V CC (V)t I N V H (n s )Note 1:Specifications are 100% tested at T A = +25°C. Limits over temperature are guaranteed by design.Detailed DescriptionThe MAX3180E–MAX3183E are EIA/TIA-232 and V.28/V.24communications receivers that convert RS -232signals to CMOS logic levels. They operate on a +3V to +5.5V supply, have 1.5Mbps data rate capability, and feature enhanced electrostatic discharge (ESD) protec-tion (see ESD Protection ). All of these devices achieve a typical supply current of 0.5µA. The MAX3180E/MAX3182E have a receiver enable control (EN ). The MAX3181E/MAX3183E contain a signal invalid output (INVALID ). The MAX3180E/MAX3181E invert the ROUT signal relative to RIN (standard RS -232). The MAX3182E/MAX3183E outputs are not inverted. The devices come in tiny SOT23-5 packages.M A X 3180E –M A X 3183E±15kV ESD-Protected, 0.5µA, +3V to +5.5V ,1.5Mbps RS-232 Receivers in SOT23-54_______________________________________________________________________________________25353045405550603.03.54.04.55.05.5RIN TO INVALID LOW vs. V CCM A X 3180E -03V CC (V)t I N V L (µs )Typical Operating Characteristics (continued)(V CC = +5V, T A = +25°C, unless otherwise noted.)5V010V 0-10V RINROUTENABLE5V 0500ns/divMAX3180EENABLE ASSERTION TO ROUT RESPONSEV CC = 5.0V R L = 50k ΩC L = 100pFReceiver Output EnablePin DescriptionFUNCTIONOutput of the Valid Input Detector Inverting Receiver Output Figure 1. Receiver Propagation-Delay Timing Noninverting Receiver OutputSignal Invalid DetectorIf no valid signal levels appear on RIN for 30µs (typ),INVALID goes low. This event typically occurs if the RS -232 cable is disconnected, or if the connected peripheral transmitter is turned off. INVALID goes high when a valid level is applied to the RS -232 receiver input. Figure 2 shows the input levels and timing dia-gram for INVALID operation.Enable InputThe MAX3180E/MAX3182E feature an enable input (EN ). Drive EN high to force ROUT into a high-imped-ance state. In this state, the devices ignore incoming RS-232 signals. Pull EN low for normal operation.ESD ProtectionAs with all Maxim devices, ES D protection structures are incorporated on all pins to protect against ES D encountered during handling and assembly. The receiver inputs of the MAX3180E–MAX3183E have extra protection against static electricity. Maxim’s engineers have developed state-of-the-art structures enabling these pins to withstand ESD up to ±15kV without dam-age or latchup. The receiver inputs of the MAX3180E–MAX3183E are characterized for protection to the fol-lowing limits:•±15kV using the Human Body Model•±8kV using the Contact Discharge method specified in IEC 1000-4-2•±15kV using the Air-Gap Discharge method speci-fied in IEC 1000-4-2Human Body ModelFigure 3 shows the Human Body Model, and Figure 4shows the current waveform it generates when dis-charged into a low impedance. This model consists ofa 100pF capacitor charged to the ESD voltage of inter-est, and then discharged into the test device through a 1.5k Ωresistor.MAX3180E–MAX3183E±15kV ESD-Protected, 0.5µA, +3V to +5.5V ,1.5Mbps RS-232 Receivers in SOT23-5_______________________________________________________________________________________5Figure 3. Human Body ESD Test ModelFigure 4. Human Body Model Current WaveformFigure 2. Input Levels and INVALID TimingM A X 3180E –M A X 3183EIEC 1000-4-2The IEC 1000-4-2 standard covers ES D testing and performance of finished equipment; it does not specifi-cally refer to ICs. The MAX3180E–MAX3183E enable the design of equipment that meets the highest level (Level 4) of IEC 1000-4-2 without the need for additional ESD-protection components.The major difference between tests done using the Human Body Model and IEC 1000-4-2 is higher peak current in IEC 1000-4-2. Because series resistance is lower in the IEC 1000-4-2 model, the ES D withstand voltage measured to this standard is generally lower than that measured using the Human Body. Figure 5shows the IEC 1000-4-2 model, and Figure 6 shows thecurrent waveform for the ±8kV IEC 1000-4-2 Level 4ESD Contact Discharge test.The Air-Gap test involves approaching the device with a charged probe. The Contact Discharge method con-nects the probe to the device before the probe is ener-gized.Power-Supply DecouplingIn most circumstances, a 0.1µF V CC bypass capacitor is adequate. Connect the bypass capacitor as close to the IC as possible.±15kV ESD-Protected, 0.5µA, +3V to +5.5V ,1.5Mbps RS-232 Receivers in SOT23-56_______________________________________________________________________________________Figure 5. IEC 1000-4-2 ESD Test ModelFigure 6. IEC 1000-4-2 ESD Generator Current WaveformMAX3180E–MAX3183E±15kV ESD-Protected, 0.5µA, +3V to +5.5V ,1.5Mbps RS-232 Receivers in SOT23-5_______________________________________________________________________________________7Pin Configurations/Functional Diagrams___________________Chip InformationTRANSISTOR COUNT: 41M A X 3180E –M A X 3183E±15kV ESD-Protected, 0.5µA, +3V to +5.5V ,1.5Mbps RS-232 Receivers in SOT23-5Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.8_____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600©1999 Maxim Integrated ProductsPrinted USAis a registered trademark of Maxim Integrated Products.Package Information。
MAX6358TWUT-T中文资料
MAX6358_ _UT-T -40°C to +85°C 6 SOT23-6 MAX6359_ _UT-T -40°C to +85°C 6 SOT23-6 MAX6360_ _UT-T -40°C to +85°C 6 SOT23-6 SV 2.93 1.58 * The _ _ are placeholders for the threshold voltage levels of the UW 2.78 1.67 devices. Substitute the part number suffix in the Voltage ThresUV 2.78 1.58 hold Levels table for the desired voltage level. All devices are available in tape-and-reel only. There is a 2500 piece minimum RW 2.63 1.67 order increment for the SOT package. RV 2.63 1.58 Devices are available in both leaded and lead-free packaging. Note: Standard versions are shown in bold. Sample stock is genSpecify lead-free by replacing “-T” with “+T” when ordering. erally held on the standard versions only. Contact factory for availPin Configurations appear at end of data sheet. ability. Selector Guide appears at end of data sheet. ________________________________________________________________ Maxim Integrated Products 1
MAX882中文资料
19-0275; Rev 0; 12/94
5V/3.3V or Adjustable, Low-Dropout, Low IQ, 200mA Linear Regulators
_______________General Description
The MAX882/MAX883/MAX884 linear regulators maximize battery life by combining ultra-low supply currents and low dropout voltages. They feature 200mA output current capability at up to +125°C junction temperature and come in a 1.5W SOIC package. The 1.5W package (compared to 0.47W for standard SOIC packages) allows a wider operating range for the input voltage and output current. The MAX882/MAX883/MAX884 use a Pchannel MOSFET pass transistor to maintain a low 11µA (15µA max) supply current from no-load to the full 200mA output. Unlike earlier bipolar regulators, there are no PNP base current losses that increase with output current. And, in dropout, the MOSFET does not suffer from excessive base currents that occur when PNP transistors go into saturation. Typical dropout voltages are 220mV at 5V and 200mA, or 320mV at 3.3V and 200mA. The MAX882 features a 7µA standby mode that disables the output but keeps the reference, low-battery comparator, and biasing circuitry alive. The MAX883/MAX884 feature a shutdown (OFF) mode that turns off all circuitry, reducing supply current to less than 1µA. All three devices include a low-battery-detection comparator, foldback current limiting, reverse-current protection, and thermal overload protection. The output is preset at 3.3V for the MAX882/MAX884 and 5V for the MAX883. In addition, all devices employ Dual Mode™ operation, allowing user-adjustable outputs from 1.25V to 11V using external resistors. The input voltage supply range is 2.7V to 11.5V. For low-dropout linear regulators with output currents up to 500mA, refer to the MAX603/MAX604 data sheet.
MAX830中文资料
STEP-DOWN CONVERTER
* CoilCraft DO3316-104
________________________________________________________________ Maxim Integrated Products
1
Call toll free 1-800-998-8800 for free samples or literature.
* THIS THERMAL RESISTANCE NUMBER IS WITH THE DEVICE WELL MOUNTED ON 1 oz. COPPER WITH THERMAL PASTE BETWEEN THE IC AND THE UNDERLYING GROUND PLANE. LOWER THERMAL RESISTANCE IS POSSIBLE (SEE APPLICATIONS SECTION).
NUAL KIT MA ATION U EET L H A S V A E T WS DA FOLLO
___________________________Features
o Input Range: Up to 30V o 1A On-Chip Power Switch o Adjustable Output (MAX830) Fixed Outputs: 5V (MAX831) 3.3V (MAX832) 3V (MAX833) o 100kHz Switching Frequency o Excellent Dynamic Characteristics o Few External Components o 8mA Quiescent Current o 16-Pin SO Package o Evaluation Kit Available
MAX809SN160T1资料
MAX809 Series,MAX810 SeriesVery Low Supply Current 3-Pin Microprocessor Reset MonitorsThe MAX809 and MAX810 are cost–effective system supervisor circuits designed to monitor V CC in digital systems and provide a reset signal to the host processor when necessary. No external components are required.The reset output is driven active within 10 µsec of V CC falling through the reset voltage threshold. Reset is maintained active for a minimum of 140 msec after V CC rises above the reset threshold. The MAX810 has an active–high RESET output while the MAX809 has an active–low RESET output. The output of the MAX809 is guaranteed valid down to V CC = 1.0 V. Both devices are available in a SOT–23 package.The MAX809/810 are optimized to reject fast transient glitches on the V CC line. Low supply current of 1.0 µA (V CC= 3.2 V) makes these devices suitable for battery powered applications.Features•Precision V CC Monitor for 2.5 V, 3.0 V, 3.3 V, and 5.0 V Supplies •Precision Monitoring V oltages from 1.6 V to 4.9 V Availablein 100 mV Steps•140 msec Guaranteed Minimum RESET Output Duration •RESET Output Guaranteed to V CC = 1.0 V•Low Supply Current•V CC Transient Immunity•Small SOT–23 Package•No External Components•Wide Operating Temperature: –40°C to 105°CTypical Applications•Computers•Embedded Systems•Battery Powered Equipment•Critical µP Power Supply MonitoringV CCFigure 1. Typical Application DiagramDevice Package ShippingORDERING INFORMATIONMAX809xTR SOT–233000 Tape/Reel MAX809SNxxxT1SOT–233000 Tape/Reel NOTE:*SOT–23 is equivalent to JEDEC (TO–236) **RESET is for MAX809***RESET is for MAX810SOT–23(TO–236)CASE 318PIN CONFIGURATION312V CCGNDRESET**SOT–23*(Top View)xx, xxx= Specific Device Codem= Date Codey= Yearw= Work WeekMARKINGDIAGRAMS32xxxm1(RESET)***MAX810xTR SOT–233000 Tape/ReelSee general marking information in the device marking section on page 8 of this data sheet.DEVICE MARKING INFORMATION NOTE: The “x” and “xxx” denotes a suffix for V cc voltage threshold options – see page 8 for more details.32xxyw1See specific device markinginformation on page 8.PIN DESCRIPTIONABSOLUTE MAXIMUM RATINGS* (Note 1)1.This device series contains ESD protection and exceeds the following tests:Human Body Model 2000 V per MIL–STD–883, Method 3015. Machine Model Method 350 V.2.The maximum package power dissipation limit must not be exceeded.P D +T J(max)*T Aq JAwith T J(max) = 150°C ELECTRICAL CHARACTERISTICS T A = –40°C to +105°C unless otherwise noted. Typical values are at T A = +25°C. (Note 3)The following data is given for MAX809 threshold levels: 1.60 V, 2.32 V, 2.93 V, 4.63 V and 4.90 V.AELECTRICAL CHARACTERISTICS(continued) T A = –40°C to +105°C unless otherwise noted. Typical values are at T A = +25°C. (Note 4) The following data is given for MAX809 threshold levels: 1.60 V, 2.32 V, 2.93 V, 4.63 V and 4.90 V.A5.Contact your ON Semiconductor sales representative for other threshold voltage options.ELECTRICAL CHARACTERISTICS (V CC = Full Range, T A = –40°C to +85°C unless otherwise noted. Typical values are at T A = +25°C, V CC = 5.0 V for L/M/J, 3.3 V for T/S, 3.0 V for R) (Note 6) The following data is given for MAX809 threshold levels: 2.63 V, 3.08 V, 4.00 V and 4.38 V; MAX810 threshold levels: 2.63 V, 2.93 V, 3.08 V, 4.38 V and 4.63 V.AAPPLICATIONS INFORMATIONV CC Transient RejectionThe MAX809 provides accurate V CC monitoring and reset timing during power–up, power–down, and brownout/sag conditions, and rejects negative–going transients (glitches)on the power supply line. Figure 2 shows the maximum transient duration vs. maximum negative excursion (overdrive) for glitch rejection. Any combination of duration and overdrive which lies under the curve will not generate a reset signal. Combinations above the curve are detected as a brownout or power–down. Typically, transient that goes 100 mV below the reset threshold and lasts 5 µs or less will not cause a reset pulse. Transient immunity can be improved by adding a capacitor in close proximity to the V CC pin of the MAX809.Figure 2. Maximum Transient Duration vs. Overdrivefor Glitch Rejection at 25°CV CC10.010080110.060.0M A X I M U M T R A N S I E N T D U R A T I O N (µs e c )20120RESET COMPARATOR OVERDRIVE (mV)160.06040RESET Signal Integrity During Power–DownThe MAX809 RESET output is valid to V CC = 1.0 V .Below this voltage the output becomes an “open circuit” and does not sink current. This means CMOS logic inputs to the µP will be floating at an undetermined voltage. Most digital systems are completely shutdown well above this voltage.However, in situations where RESET must be maintainedvalid to V CC = 0 V , a pull–down resistor must be connected from RESET to ground to discharge stray capacitances and hold the output low (Figure 3). This resistor value, though not critical, should be chosen such that it does not appreciably load RESET under normal operation (100 k W will be suitable for most applications).Figure 3. Ensuring RESET Valid to V CC = 0 VProcessors With Bidirectional I/O PinsSome µP’s (such as Motorola 68HC11) have bi–directional reset pins. Depending on the current drive capability of the processor pin, an indeterminate logic level may result if there is a logic conflict. This can be avoided by adding a 4.7 k W resistor in series with the output of the MAX809 (Figure 4). If there are other components in the system which require a reset signal, they should be buffered so as not to load the reset line. If the other components are required to follow the reset I/O of the µP, the buffer should be connected as shown with the solid line.Figure 4. Interfacing to Bidirectional Reset I/OBUFFERED RESETThe following data is given for MAX809 threshold levels: 1.60 V, 2.32 V, 2.93 V, 4.63 V and 4.90 V.1.10S U P P L Y C U R R E N T I N M I C R O A M PTEMPERATURE (°C)N O R M A L I Z E D P O W E R –U P R E S E T T I M E O U T–404020–206080Figure 7. Normalized Power–Up Reset vs.Temperature Figure 8. Normalized Reset Threshold Voltagevs. TemperatureTEMPERATURE (°C)–404020–206080The following data is given for MAX809 threshold levels: 2.63 V, 3.08 V, 4.00 V and 4.38 V;MAX810 threshold levels: 2.63 V, 2.93 V, 3.08 V, 4.38 V and 4.63 V.S U P P L Y C U R R E N T ( A )m 040206080100P O W E R -D O W N R E S E T D E L A Y ( s e c )m TEMPERATURE (C °)-40-200204085Figure 13. Power–Up Reset Timeout vs.Temperature TEMPERATURE (C °)-40-20020406085225235230240245250P O W E R -U P R E S E T T I M E O U T (m s e c )60Figure 14. Normalized Reset Threshold vs.TemperatureTAPING FORMComponent Taping Orientation for 3L SOT–23 (JEDEC–236) Devices(Mark Right Side Up)SOT–23Package Carrier Width (W)Pitch (P)Part Per Full ReelReel Size 8 mm4 mm30007 inchesTape & Reel Specifications TableMARKING AND THRESHOLD INFORMATIONm = Date Codey = Yearw = Work WeekPACKAGE DIMENSIONSSOT–23PLASTIC PACKAGE (TO–236)CASE 318–08ISSUE AHNOTES:1.DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982.2.CONTROLLING DIMENSION: INCH.3.MAXIMUM LEAD THICKNESS INCLUDES LEADNotesNotes11ON Semiconductor and are trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC reserves the right to make changes without further notice to any products herein. SCILLC makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does SCILLC assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation special, consequential or incidental damages. “Typical” parameters which may be provided in SCILLC data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All operating parameters, including “Typicals” must be validated for each customer application by customer’s technical experts. SCILLC does not convey any license under its patent rights nor the rights of others.SCILLC products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the SCILLC product could create a situation where personal injury or death may occur. Should Buyer purchase or use SCILLC products for any such unintended or unauthorized application, Buyer shall indemnify and hold SCILLC and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that SCILLC was negligent regarding the design or manufacture of the part. SCILLC is an Equal Opportunity/Affirmative Action Employer. PUBLICATION ORDERING INFORMATIONJAPAN: ON Semiconductor, Japan Customer Focus Center4–32–1 Nishi–Gotanda, Shinagawa–ku, Tokyo, Japan 141–0031Phone: 81–3–5740–2700Email: r14525@。
MAX3841中文资料
PARAMETER
SYMBOL
CONDITIONS
MIN TYP MAX UNITS
Core Supply Current Data Rate
ICC
Excluding CML termination currents
(Note 1)
65
90
mA
0
12.5 Gbps
CML Input Differential CML Input Common Mode
Termination Currents)
Ordering Information
PART
TEMP RANGE
MAX3841ETG -40°C to +85°C
PINPACKAGE
24 Thin QFN
PKG. CODE
T2444-1
Pin Configuration appears at end of data sheet.
12
dB
CML Output Differential CML Output Termination
VOUT
(Note 2) Single ended
400
500
42.5
50
600 57.5
mVP-P Ω
CML Output Transition Time Deterministic Jitter Random Jitter Propagation Delay
Note 4: Measured at 9.953Gbps using a pattern of 100 ones, 27 - 1 PRBS, 100 zeros, 27 - 1 PRBS, and at 12.5Gbps using a ±K28.5 pattern. VCC_IN = VCC_OUT = 1.8V, and VIN = 400mVP-P differential.
MAX6818中文资料
Ordering Information
PART
TEMP. RANGE
PIN-
SOT
PACKAGE TOP MARK
MAX6816EUS-T -40°C to +85°C 4 SOT143
KABA
MAX6817EUT-T -40°C to +85°C 6 SOT23-6
OUT Short-Circuit Duration (One or Two Outputs to GND)....................................Continuous
Continuous Power Dissipation (TA = +70°C) 4-Pin SOT143 (derate 4.0mW/°C above +70°C)..........320mW 6-Pin SOT23 (derate 8.7mW/°C above +70°C)............691mW 20-Pin SSOP (derate 8.0mW/°C above +70°C) ...........640mW
Input Threshold
Input Hysteresis Input Pull-Up Resistance IN Input Current Input Voltage Range Undervoltage-Lockout Threshold
SYMBOL VCC ICC
tDP
VIL
VIH
CONDITIONS
Operating Temperature Range ...........................-40°C to +85°C Storage Temperature Range .............................-65°C to +160°C Lead Temperature (soldering, 10sec) .............................+300°C
MAX6387XS18D7中文资料
MAX6387XS18D7中⽂资料General Description The MAX6381–MAX6390 microprocessor (µP) supervisory circuits monitor power-supply voltages from +1.8V to +5.0V while consuming only 3µA of supply current at +1.8V. Whenever V CC falls below the factory-set reset thresholds, the reset output asserts and remains assert-ed for a minimum reset timeout period after V CC rises above the reset threshold. Reset thresholds are available from +1.58V to +4.63V, in approximately 100mV incre-ments. Seven minimum reset timeout delays ranging from 1ms to 1200ms are available.The MAX6381/MAX6384/MAX6387 have a push-pull active-low reset output. The MAX6382/MAX6385/ MAX6388 have a push-pull active-high reset output, and the MAX6383/MAX6386/MAX6389/MAX6390 have an open-drain active-low reset output. The MAX6384/MAX6385/MAX6386 also feature a debounced manual reset input (with internal pullup resistor). The MAX6387/MAX6388/MAX6389 have an auxiliary input for monitoring a second voltage. The MAX6390 offers a manual reset input with a longer V CC reset timeout period (1120ms or 1200ms) and a shorter manual reset timeout (140ms or 150ms). The MAX6381/MAX6382/MAX6383 are available in 3-pin SC70 and6-pinµDFN packages and the MAX6384–MAX6390 are available in 4-pin SC70 andFeaturesFactory-Set Reset Threshold Voltages Rangingfrom +1.58V to +4.63V in Approximately 100mVIncrements±2.5% Reset Threshold Accuracy OverTemperature (-40°C to +125°C)Seven Reset Timeout Periods Available: 1ms,20ms, 140ms, 280ms, 560ms, 1120ms,1200ms (min)3 Reset Output OptionsActive-Low Push-PullActive-High Push-PullActive-Low Open-DrainReset Output State Guaranteed ValidDown to V CC= 1VManual Reset Input (MAX6384/MAX6385/MAX6386)Auxiliary RESET IN(MAX6387/MAX6388/MAX6389)V CC Reset Timeout (1120ms or 1200ms)/ManualReset Timeout (140ms or 150ms) (MAX6390)Negative-Going V CC Transient ImmunityLow Power Consumption of 6µA at +3.6Vand 3µA at +1.8VPin Compatible withMAX809/MAX810/MAX803/MAX6326/MAX6327/MAX6328/MAX6346/MAX6347/MAX6348,and MAX6711/MAX6712/MAX6713Tiny 3-Pin/4-Pin SC70 and 6-Pin µDFN PackagesMAX6381–MAX6390 SC70/µDFN, Single/Dual Low-Voltage,Low-Power µP Reset Circuits ________________________________________________________________Maxim Integrated Products1Pin Configurations19-1839; Rev 4; 4/07Ordering InformationOrdering Information continued at end of data sheet.Typi cal Operati ng Ci rcui t appears at end of data sheet.Selector Guide appears at end of data sheet.after "XR", "XS", or "LT." Insert reset timeout delay (see ResetTimeout Delay table) after "D" to complete the part number.Sample stock is generally held on standard versions only (seeStandard Versions table). Standard versions have an orderincrement requirement of 2500 pieces. Nonstandard versionshave an order increment requirement of 10,000 pieces.Contact factory for availability of nonstandard versions.+Denotes a lead-free package.For pricing, delivery, and ordering information,please contact Maxim Direct at 1-888-629-4642,or visit Maxim’s website at /doc/5700977901f69e3143329415.html .ComputersControllersIntelligent InstrumentsCritical µP and µCPower MonitoringPortable/Battery-Powered EquipmentDual Voltage SystemsM A X 6381–M A X 6390SC70/µDFN, Single/Dual Low-Voltage, Low-Power µP Reset CircuitsABSOLUTE MAXIMUM RATINGSELECTRICAL CHARACTERISTICS(V CC = full range, T A = -40°C to +125°C, unless otherwise specified. Typical values are at T A = +25°C.) (Note 1)Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.V CC to GND..........................................................-0.3V to +6.0V RESET Open-Drain Output....................................-0.3V to +6.0V RESET , RESET (push-pull output)..............-0.3V to (V CC + 0.3V)MR , RESET IN.............................................-0.3V to (V CC + 0.3V)Input Current (V CC ).............................................................20mA Output Current (all pins).....................................................20mAContinuous Power Dissipation (T A = +70°C)3-Pin SC70 (derate 2.9mW/°C above +70°C)..............235mW 4-Pin SC70 (derate 3.1mW/°C above +70°C)..............245mW 6-Pin µDFN (derate 2.1mW/°C above +70°C)..........167.7mW Operating Temperature Range .........................-40°C to+125°C Storage Temperature Range.............................-65°C to +150°C Lead Temperature (soldering,10s).................................+300°CMAX6381–MAX6390SC70/µDFN, Single/Dual Low-Voltage,Low-Power µP Reset Circuits_______________________________________________________________________________________3M A X 6381–M A X 6390SC70/µDFN, Single/Dual Low-Voltage, Low-Power µP Reset Circuits4______________________________________________________________________________________Typical Operating Characteristics(T A = +25°C, unless otherwise noted.)215436789-40-105-25203550658095110125SUPPLY CURRENT vs. TEMPERATURE(NO LOAD)TEMPERATURE (°C)S U P P L Y C U R R E N T (µA )25292735333137394143-40-105-25203550658095110125POWER-DOWN RESET DELAYvs. TEMPERATURETEMPERATURE (°C)P O W E R -D O W N R E S E T D E L A Y (µs )0.940.980.961.021.001.061.041.08-40-10520-253550658095110125 NORMALIZED POWER-UP RESET TIMEOUTvs. TEMPERATUREM A X 6381/90 t o c 03TEMPERATURE (°C)N O R M A L I Z E D R E S E T T I M E O U T P E R I O D0.9900.9851.0150.9950.9901.0001.0051.0101.020-40-10520-253550958011065125 M A X 6381/90 t o c 04TEMPERATURE (°C)N O R M A L I Z E D R E S E T TH R E S H O L D NORMALIZED RESET THRESHOLDvs. TEMPERATURE00.40.20.80.61.01.2063912OUTPUT-VOLTAGE LOW vs. SINK CURRENTI SINK (mA)V O L (V )01.00.52.01.52.53.00500750250100012501500OUTPUT-VOLTAGE HIGH vs. SOURCE CURRENTI SOURCE (µA)V O H (V )45001100010010MAXIMUM TRANSIENT DURATION vs. RESET COMPARATOR OVERDRIVE15050350250500200100400300RESET COMPARATOR OVERDRIVE, V TH - V CC (mV)M A X I M U M T R A N S I E N T D U R A T I O N (µs )3.53.93.74.54.34.14.74.95.35.15.5-40-105-25203550658095110125RESET IN TO RESET DELAYvs. TEMPERATUREM A X 6381/90 t o c 08TEMPERATURE (°C)R E S E T I N D E L A Y (µs )MAX6381–MAX6390SC70/µDFN, Single/Dual Low-Voltage,Low-Power µP Reset CircuitsPin DescriptionM A X 6381–M A X 6390SC70/µDFN, Single/Dual Low-Voltage, Low-Power µP Reset Circuits6_______________________________________________________________________________________ Detailed DescriptionRESET OutputA µP reset input starts the µP in a known state. These µP supervisory circuits assert reset to prevent code execution errors during power-up, power-down, or brownout conditions.Reset asserts when V CC is below the reset threshold;once V CC exceeds the reset threshold, an internal timer keeps the reset output asserted for the reset timeout period. After this interval, reset output deasserts. Reset output is guaranteed to bein the correct logic state for V CC ≥1V.Manual Reset Input (MAX6384/MAX6385/MAX6386/MAX6390)Many µP-based products require manual reset capabil-ity, allowing the operator, a test technician, or external logic circuitry to initiate a reset. A logic low on MR asserts reset. Reset remains asserted while MR is low,and for the reset active timeout period (t RP ) after MR returns high. This input has an internal 63k ?pullup resistor (1.56k ?for MAX6390), so it can be left uncon-nected if it is not used. MR can be driven with TTL or CMOS logic levels, or with open-drain/collector outputs.Connect a normally open momentary switch from MR to G ND to create a manual-reset function; external debounce circuitry is not required. If MR is driven from long cables or if the device is used in a noisy environ-ment, connecting a 0.1µF capacitor from MR to G ND provides additional noise immunity.RESET IN Comparator(MAX6387/MAX6388/MAX6389)RESET IN is compared to an internal +1.27V reference.If the voltage at RESET IN is less than 1.27V, reset asserts. Use the RESET IN comparator as a user-adjustable reset detector or as a secondary power-sup-ply monitor by implementing a resistor-divider at RESET IN (shown in Figure 1). Reset asserts when either V CC or RESET IN falls below its respective threshold volt-age. Use the following equation to set the threshold:V INTH = V THRST (R1/R2 + 1)where V THRST = +1.27V. To simplify the resistor selec-tion, choose a value of R2 and calculate R1:R1 = R2 [(V INTH /V THRST ) - 1]Since the input current at RESET IN is 50nA (max),large values can be used for R2 with no significant loss in accuracy.___________Applications InformationNegative-Going V CC TransientsIn addition to issuing a reset to the µP during power-up,power-down, and brownout conditions, the MAX6381–MAX6390 are relatively immune to short dura-tion negative-going V CC transients (glitches).The Typical Operating Characteristics section shows the Maximum Transient Durations vs. Reset Comparator Overdrive, for which the MAX6381–MAX6390 do not generate a reset pulse. This graph was generated usinga negative-going pulse applied to V CC , starting above the actual reset threshold and ending below it by the magnitude indicated (reset comparator overdrive). The graph indicates the typical maximum pulse width a neg-ative-going V CC transient may have without causing a reset pulse to be issued. As the magnitude of the tran-sient increases (goes farther below the reset threshold),the maximum allowable pulse width decreases. A 0.1µF capacitor mounted as close as possible to V CC provides additional transient immunity.Ensuring a Valid RESET Output Down to V CC = 0VThe MAX6381–MAX6390 are guaranteed to operate properly down to V CC = 1V. In applications that require valid reset levels down to V CC = 0V, a pulldown resistor to active-low outputs (push/pull only, Figure 2) and a pullup resistor to active-high outputs (push/pull only)will ensure that the reset line is valid while the reset out-put can no longer sink or source current. This schemedoes not work with the open-drain outputs of the MAX6383/MAX6386/MAX6389/MAX6390. The resistor value used is not critical, but it must be small enough not to load the reset output when V CC is above the reset threshold. For most applications, 100k ?is ade-quate.MAX6381–MAX6390SC70/µDFN, Single/Dual Low-Voltage,Low-Power µP Reset Circuits_______________________________________________________________________________________7M A X 6381–M A X 6390SC70/µDFN, Single/Dual Low-Voltage, Low-Power µP Reset Circuits 8_______________________________________________________________________________________ Selector GuideOrdering Information (continued)Note:Insert reset threshold suffix (see Reset Threshold table)after "XR", "XS", or "LT." Insert reset timeout delay (see Reset Timeout Delay table) after "D" to complete the part number.Sample stock is generally held on standard versions only (see Standard Versions table). Standard versions have an order increment requirement of 2500 pieces. Nonstandard versions have an order increment requirement of 10,000 pieces.Contact factory for availability of nonstandard versions.*MAX6390 is available with D4 or D7 timing only.+Denotes a lead-free package.MAX6381–MAX6390SC70/µDFN, Single/Dual Low-Voltage,Low-Power µP Reset Circuits_______________________________________________________________________________________9Chip InformationTRANSISTOR COUNT: 647PROCESS: BiCMOSPin Configurations (continued)M A X 6381–M A X 6390SC70/µDFN, Single/Dual Low-Voltage, Low-Power µP Reset Circuits10______________________________________________________________________________________ Package Information(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,go to /doc/5700977901f69e3143329415.html /packages .)MAX6381–MAX6390SC70/µDFN, Single/Dual Low-Voltage,Low-Power µP Reset Circuits______________________________________________________________________________________11Package Information (continued)(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,go to /doc/5700977901f69e3143329415.html /packages .)M A X 6381–M A X 6390SC70/µDFN, Single/Dual Low-Voltage, Low-Power µP Reset Circuits12______________________________________________________________________________________ Package Information (continued)(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,go to /doc/5700977901f69e3143329415.html /packages .)SC70/µDFN, Single/Dual Low-Voltage,Low-Power µP Reset CircuitsMaxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600____________________13?2007 Maxim Integrated Productsis a registered trademark of Maxim Integrated Products, Inc.MAX6381–MAX6390Package Information (continued)(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,go to /doc/5700977901f69e3143329415.html /packages .)Revision HistoryPages changed at Rev 4: Title on all pages, 1, 2, 5,7–13。
MAX630CSA+中文资料
General DescriptionMaxim’s MAX630 and MAX4193 CMOS DC-DC regula-tors are designed for simple, efficient, minimum-size DC-DC converter circuits in the 5mW to 5W range. The MAX630 and MAX4193 provide all control and power handling functions in a compact 8-pin package: a 1.31V bandgap reference, an oscillator, a voltage com-parator, and a 375mA N-channel output MOSF ET. A comparator is also provided for low-battery detection.Operating current is only 70µA and is nearly indepen-dent of output switch current or duty cycle. A logic-level input shuts down the regulator to less than 1µA quies-cent current. Low-current operation ensures high effi-ciency even in low-power battery-operated systems.The MAX630 and MAX4193 are compatible with most battery voltages, operating from 2.0V to 16.5V.The devices are pin compatible with the Raytheon bipo-lar circuits, RC4191/2/3, while providing significantly improved efficiency and low-voltage operation. Maxim also manufactures the MAX631, MAX632, and MAX633DC-DC converters, which reduce the external compo-nent count in fixed-output 5V, 12V, and 15V circuits.See Table 2 at the end of this data sheet for a summary of other Maxim DC-DC converters.Applications+5V to +15V DC-DC ConvertersHigh-Efficiency Battery-Powered DC-DC Converters+3V to +5V DC-DC Converters 9V Battery Life ExtensionUninterruptible 5V Power Supplies5mW to 5W Switch-Mode Power SuppliesFeatures♦High Efficiency—85% (typ)♦70µA Typical Operating Current ♦1µA Maximum Quiescent Current ♦2.0V to 16.5V Operation♦525mA (Peak) Onboard Drive Capability ♦±1.5% Output Voltage Accuracy (MAX630)♦Low-Battery Detector♦Compact 8-Pin Mini-DIP and SO Packages ♦Pin Compatible with RC4191/2/3MAX630/MAX4193CMOS Micropower Step-UpSwitching Regulator________________________________________________________________Maxim Integrated Products 1Pin ConfigurationOrdering InformationTypical Operating Circuit19-0915; Rev 2; 9/08For pricing, delivery, and ordering information,please contact Maxim/Dallas Direct!at 1-888-629-4642, or visit Maxim’s website at .*Dice are specified at T A = +25°C. Contact factory for dice specifications.**Contact factory for availability and processing to MIL-STD-883.†Contact factory for availibility.M A X 630/M A X 4193CMOS Micropower Step-Up Switching Regulator 2_______________________________________________________________________________________ABSOLUTE MAXIMUM RATINGSELECTRICAL CHARACTERISTICSStresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.Supply Voltage.......................................................................18V Storage Temperature Range ............................-65°C to +160°C Lead Temperature (soldering, 10s).................................+300°C Operating Temperature RangeMAX630C, MAX4193C........................................0°C to +70°C MAX630E, MAX4193E.....................................-40°C to +85°C MAX630M, MAX4193M..................................-55°C to +125°CPower Dissipation8-Pin PDIP (derate 6.25mW/°C above +50°C).............468mW 8-Pin SO (derate 5.88mW/°C above +50°C)................441mW 8-Pin CERDIP (derate 8.33mW/°C above +50°C)........833mW Input Voltage (Pins 1, 2, 6, 7).....................-0.3V to (+V S + 0.3V)Output Voltage, L X and LBD..................................................18V L X Output Current..................................................525mA (Peak)LBD Output Current............................................................50mAMAX630/MAX4193CMOS Micropower Step-UpSwitching Regulator_______________________________________________________________________________________3L X ON-RESISTANCE vs.TEMPERATURETEMPERATURE (°C)L X R O N (Ω)100755025-25-5024680125SUPPLY CURRENT vs.TEMPERATUREM A X 630/4193 t o c 02TEMPERATURE (°C)I S (μA )100755025-25-50402080601201001400125SUPPLY CURRENT vs.SUPPLY VOLTAGEM A X 630/4193 t o c 03+V S (V)I S (μA )14121086425015010025020030016Typical Operating Characteristics(T A = +25°C, unless otherwise noted.)ELECTRICAL CHARACTERISTICSNote 1:Guaranteed by correlation with DC pulse measurements.Note 2:The operating frequency range is guaranteed by design and verified with sample testing.Detailed DescriptionThe operation of the MAX630 can best be understood by examining the voltage regulating loop of F igure 1.R1 and R2 divide the output voltage, which is com-pared with the 1.3V internal reference by comparator COMP1. When the output voltage is lower than desired,the comparator output goes high and the oscillator out-put pulses are passed through the NOR gate latch,turning on the output N-channel MOSFET at pin 3, L X .As long as the output voltage is less than the desired voltage, pin 3 drives the inductor with a series of pulses at the oscillator frequency.Each time the output N-channel MOSFET is turned on,the current through the external coil, L1, increases,storing energy in the coil. Each time the output turns off,the voltage across the coil reverses sign and the volt-age at L X rises until the catch diode, D1, is forward biased, delivering power to the output.When the output voltage reaches the desired level,1.31V x (1 + R1 / R2), the comparator output goes low and the inductor is no longer pulsed. Current is then supplied by the filter capacitor, C1, until the output volt-age drops below the threshold, and once again L X is switched on, repeating the cycle. The average duty cycle at L X is directly proportional to the output current.Output Driver (L X Pin)The MAX630/MAX4193 output device is a large N-channel MOSFET with an on-resistance of 4Ωand a peak current rating of 525mA. One well-known advan-tage that MOSF ETs have over bipolar transistors in switching applications is higher speed, which reduces switching losses and allows the use of smaller, lighter,less costly magnetic components. Also important is that MOSF ETs, unlike bipolar transistors, do not require base current that, in low-power DC-DC converters,often accounts for a major portion of input power.The operating current of the MAX630 and MAX4193increases by approximately 1µA/kHz at maximum power output due to the charging current required by the gate capacitance of the L X output driver (e.g., 40µA increase at a 40kHz operating frequency). In compari-son, equivalent bipolar circuits typically drive their NPN L X output device with 2mA of base drive, causing the bipolar circuit’s operating current to increase by a fac-tor of 10 between no load and full load.OscillatorThe oscillator frequency is set by a single external, low-cost ceramic capacitor connected to pin 2, C X . 47pF sets the oscillator to 40kHz, a reasonable compromise between lower switching losses at low frequencies and reduced inductor size at higher frequencies.M A X 630/M A X 4193CMOS Micropower Step-Up Switching Regulator 4_______________________________________________________________________________________Low-Battery DetectorThe low-battery detector compares the voltage on LBR with the internal 1.31V reference. The output, LBD, is an open-drain N-channel MOSFET. In addition to detecting and warning of a low battery voltage, the comparator can also perform other voltage-monitoring operations such as power-failure detection.Another use of the low-battery detector is to lower the oscillator frequency when the input voltage goes below a specified level. Lowering the oscillator frequency increases the available output power, compensating for the decrease in available power caused by reduced input voltage (see Figure 5).Logic-Level Shutdown InputThe shutdown mode is entered whenever I C (pin 6) is driven below 0.2V or left floating. When shut down, theMAX630’s analog circuitry, oscillator, L X , and LBD out-puts are turned off. The device’s quiescent current dur-ing shutdown is typically 10nA (1µA max).Bootstrapped OperationIn most circuits, the preferred source of +V S voltage for the MAX630 and MAX4193 is the boosted output volt-age. This is often referred to as a “bootstrapped” oper-ation since the circuit figuratively “lifts” itself up.The on-resistance of the N-channel L X output decreas-es with an increase in +V S ; however, the device operat-ing current goes up with +V S (see the Typical Operating Characteristics , I S vs. +V S graph). In circuits with very low output current and input voltages greater than 3V, it may be more efficient to connect +V S direct-ly to the input voltage rather than bootstrap.MAX630/MAX4193CMOS Micropower Step-UpSwitching Regulator_______________________________________________________________________________________5Figure 1. +5V to +15V Converter and Block DiagramM A X 630/M A X 4193External ComponentsResistorsSince the LBR and V FB input bias currents are specified as 10nA (max), the current in the dividers R1/R2 and R3/R4 (Figure 1) may be as low as 1µA without signifi-cantly affecting accuracy. Normally R2 and R4 are between 10k Ωand 1M Ω, which sets the current in the voltage-dividers in the 1.3µA to 130µA range. R1 and R3 can then be calculated as follows:where V OUT is the desired output voltage and V LB isthe desired low-battery warning threshold.If the I C (shutdown) input is pulled up through a resistor rather than connected directly to +V S , the current through the pullup resistor should be a minimum of 4µAInductor ValueThe available output current from a DC-DC voltageboost converter is a function of the input voltage, exter-nal inductor value, output voltage, and the operating frequency.The inductor must 1) have the correct inductance, 2) be able to handle the required peak currents, and 3) have acceptable series resistance and core losses. If the inductance is too high, the MAX630 will not be able to deliver the desired output power, even with the L X out-put on for every oscillator cycle. The available output power can be increased by either decreasing the inductance or the frequency. Reducing the frequency increases the on-period of the L X output, thereby increasing the peak inductor current. The available out-put power is increased since it is proportional to the square of the peak inductor current (I PK ).where P OUT includes the power dissipated in the catchdiode (D1) as well as that in the load. If the inductance is too low, the current at L X may exceed the maximum rating. The minimum allowed inductor value is expressed by:where I MAX ≈525mA (peak L X current) and t ON is the on-time of the L X output.The most common MAX630 circuit is a boost-mode converter (Figure 1). When the N-channel output device is on, the current linearly rises since:At the end of the on-time (14µs for 40kHz, 55% duty-cycle oscillator) the current is:The energy in the coil is:At maximum load, this cycle is repeated 40,000 timesper second, and the power transferred through the coil is 40,000 x 5.25 = 210mW. Since the coil only supplies the voltage above the input voltage, at 15V, the DC-DC converter can supply 210mW / (15V - 5V) = 21mA. The coil provides 210mW and the battery directly supplies another 105mW, for a total of 315mW of output power. If the load draws less than 21mA, the MAX630 turns on its output only often enough to keep the output voltage at a constant 15V.Reducing the inductor value increases the available output current: lower L increases the peak current,thereby increasing the available power. The external inductor required by the MAX630 is readily obtained from a variety of suppliers (Table 1). Standard coils are suitable for most applications.Types of InductorsMolded InductorsThese are cylindrically wound coils that look similar to 1W resistors. They have the advantages of low cost and ease of handling, but have higher resistance, higher losses, and lower power handling capability than other types.102112131131104134131131ΩΩΩΩ≤≤=−≤≤=− .. ..R M R R x V VR M R R x V VOUTLBCMOS Micropower Step-Up Switching Regulator 6_______________________________________________________________________________________Potted Toroidal InductorsA typical 1mH, 0.82Ωpotted toroidal inductor (Dale TE-3Q4TA) is 0.685in in diameter by 0.385in high and mounts directly onto a PC board by its leads. Such devices offer high efficiency and mounting ease, but at a somewhat higher cost than molded inductors.Ferrite Cores (Pot Cores)Pot cores are very popular as switch-mode inductors since they offer high performance and ease of design.The coils are generally wound on a plastic bobbin,which is then placed between two pot core sections. A simple clip to hold the core sections together com-pletes the inductor. Smaller pot cores mount directly onto PC boards through the bobbin terminals. Cores come in a wide variety of sizes, often with the center posts ground down to provide an air gap. The gap pre-vents saturation while accurately defining the induc-tance per turn squared.Pot cores are suitable for all DC-DC converters, but are usually used in the higher power applications. They are also useful for experimentation since it is easy to wind coils onto the plastic bobbins.Toroidal CoresIn volume production, the toroidal core offers high per-formance, low size and weight, and low cost. They are,however, slightly more difficult for prototyping, in that manually winding turns onto a toroid is more tedious than on the plastic bobbins used with pot cores.Toroids are more efficient for a given size since the flux is more evenly distributed than in a pot core, where the effective core area differs between the post, side, top,and bottom.Since it is difficult to gap a toroid, manufacturers produce toroids using a mixture of ferromagnetic powder (typically iron or Mo-Permalloy powder) and a binder. The perme-ability is controlled by varying the amount of binder,which changes the effective gap between the ferromag-netic particles. Mo-Permalloy powder (MPP) cores have lower losses and are recommended for the highest effi-ciency, while iron powder cores are lower cost.DiodesIn most MAX630 circuits, the inductor current returns to zero before L X turns on for the next output pulse. This allows the use of slow turn-off diodes. On the other hand, the diode current abruptly goes from zero to full peak current each time L X switches off (Figure 1, D1).To avoid excessive losses, the diode must therefore have a fast turn-on time.F or low-power circuits with peak currents less than 100mA, signal diodes such as 1N4148s perform well.For higher-current circuits, or for maximum efficiency at low power, the 1N5817 series of Schottky diodes are recommended. Although 1N4001s and other general-purpose rectifiers are rated for high currents, they are unacceptable because their slow turn-on time results in excessive losses.MAX630/MAX4193CMOS Micropower Step-UpSwitching Regulator_______________________________________________________________________________________7Table 1. Coil and Core ManufacturersM A X 630/M A X 4193Filter CapacitorThe output-voltage ripple has two components, with approximately 90 degrees phase difference between them. One component is created by the change in the capacitor’s stored charge with each output pulse. The other ripple component is the product of the capacitor’s charge/discharge current and its effective series resis-tance (ESR). With low-cost aluminum electrolytic capacitors, the ESR-produced ripple is generally larger than that caused by the change in charge.where V IN is the coil input voltage, L is its inductance, f is the oscillator frequency, and ESR is the equivalent series resistance of the filter capacitor.The output ripple resulting from the change in charge on the filter capacitor is:where t CHG and t DIS are the charge and dischargetimes for the inductor (1/2f can be used for nominal cal-culations).Oscillator Capacitor, C XThe oscillator capacitor, C X , is a noncritical ceramic or silver mica capacitor. C X can also be calculated by:where f is the desired operating frequency in Hertz, and C INT is the sum of the stray capacitance on the C X pin and the internal capacitance of the package. The internal capacitance is typically 1pF for the plastic package and 3pF for the CERDIP package. Typical stray capacitances are about 3pF for normal PC board layouts, but will be significantly higher if a socket is used.Bypassing and CompensationSince the inductor-charging current can be relatively large, high currents can flow through the ground con-nection of the MAX630/MAX4193. To prevent unwanted feedback, the impedance of the ground path must be as low as possible, and supply bypassing should be used for the device.When large values (>50k Ω) are used for the voltage-setting resistors, R1 and R2 of F igure 1, stray capaci-tance at the V FB input can add a lag to the feedback response, destabilizing the regulator, increasing low-frequency ripple, and lowering efficiency. This can often be avoided by minimizing the stray capacitance at the V FB node. It can also be remedied by adding a lead compensation capacitor of 100pF to 10nF in paral-lel with R1 in Figure 1.DC-DC Converter ConfigurationsDC-DC converters come in three basic topologies:buck, boost, and buck-boost (Figure 2). The MAX630 is usually operated in the positive-voltage boost circuit,where the output voltage is greater than the input.The boost circuit is used where the input voltage is always less than the desired output and the buck circuit is used where the input is greater than the output. Thebuck-boost circuit inverts, and can be used with, inputCMOS Micropower Step-Up Switching Regulator 8_______________________________________________________________________________________Figure 2. DC-DC Converter Configurationsvoltages that are either greater or less than the output. DC-DC converters can also be classified by the control method. The two most common are pulse-width modu-lation (PWM) and pulse-frequency modulation (PF M). PWM switch-mode power-supply ICs (of which current-mode control is one variant) are well-established in high-power off-line switchers. Both PWM and PF M cir-cuits control the output voltage by varying duty cycle. In the PWM circuit, the frequency is held constant and the width of each pulse is varied. In the PFM circuit, the pulse width is held constant and duty cycle is con-trolled by changing the pulse repetition rate.The MAX630 refines the basic PFM by employing a con-stant-frequency oscillator. Its output MOSFET is switched on when the oscillator is high and the output voltages is lower than desired. If the output voltage is higher than desired, the MOSFET output is disabled for that oscillator cycle. This pulse skipping varies the average duty cycle, and thereby controls the output voltage.Note that, unlike the PWM ICs, which use an op amp as the control element, the MAX630 uses a comparator tocompare the output voltage to an onboard reference. This reduces the number of external components and operating current.Typical Applications+5V to +15V DC-DC Converter Figure 1 shows a simple circuit that generates +15V at approximately 20mA from a +5V input. The MAX630 has a ±1.5% reference accuracy, so the output voltage has an untrimmed accuracy of ±3.5% if R1 and R2 are 1% resistors. Other output voltages can also be select-ed by changing the feedback resistors. Capacitor C X sets the oscillator frequency (47pF = 40kHz), while C1 limits output ripple to about 50mV.With a low-cost molded inductor, the circuit’s efficiency is about 75%, but an inductor with lower series resis-tance such as the Dale TE3Q4TA increases efficiency to around 85%. A key to high efficiency is that the MAX630 itself is powered from the +15V output. This provides the onboard N-channel output device with 15V gate drive, lowering its on-resistance to about 4Ω. When +5V power is first applied, current flows through L1 and D1, supplying the MAX630 with 4.4V for startup.+5V to ±15V DC-DC Converter The circuit in F igure 3 is similar to that of F igure 1 except that two more windings are added to the induc-tor. The 1408 (14mm x 8mm) pot core specified is an IEC standard size available from many manufacturers (see Table 1). The -15V output is semiregulated, typi-cally varying from -13.6V to -14.4V as the +15V load current changes from no load to 20mA.2.5W, 3V to 5V DC-DC ConverterSome systems, although battery powered, need high currents for short periods, and then shut down to a low-power state. The extra circuitry of Figure 4 is designed tomeet these high-current needs. Operating in the buck-boost or flyback mode, the circuit converts -3V to +5V.The left side of Figure 4 is similar to Figure 1 and sup-plies 15V for the gate drive of the external power MOS-FET. This 15V gate drive ensures that the external deviceis completely turned on and has low on-resistance.The right side of F igure 4 is a -3V to +5V buck-boost converter. This circuit has the advantage that when theMAX630 is turned off, the output voltage falls to 0V,unlike the standard boost circuit, where the output volt-age is V BATT- 0.6V when the converter is shut down.When shut down, this circuit uses less than 10µA, withmost of the current being the leakage current of the power MOSFET.The inductor and output-filter capacitor values havebeen selected to accommodate the increased power levels. With the values indicated, this circuit can supplyup to 500mA at 5V, with 85% efficiency. Since the leftside of the circuit powers only the right-hand MAX630,the circuit starts up with battery voltages as low as1.5V, independent of the loading on the +5V output.MAX630/MAX4193CMOS Micropower Step-UpSwitching Regulator _______________________________________________________________________________________9M A X 630/M A X 4193+3V Battery to +5V DC-DC ConverterA common power-supply requirement involves conver-sion of a 2.4V or 3V battery voltage to a 5V logic sup-ply. The circuit in Figure 5 converts 3V to 5V at 40mA with 85% efficiency. When I C (pin 6) is driven low, the output voltage will be the battery voltage minus the drop across diode D1.The optional circuitry using C1, R3, and R4 lowers the oscillator frequency when the battery voltage falls to 2.0V. This lower frequency maintains the output-power capability of the circuit by increasing the peak inductor current, compensating for the reduced battery voltage.Uninterruptable +5V SupplyIn Figure 6, the MAX630 provides a continuous supply of regulated +5V, with automatic switchover between line power and battery backup. When the line-powered input voltage is at +5V, it provides 4.4V to the MAX630and trickle charges the battery. If the line-powered input falls below the battery voltage, the 3.6V battery supplies power to the MAX630, which boosts the bat-tery voltage up to +5V, thus maintaining a continuous supply to the uninterruptable +5V bus. Since the +5V output is always supplied through the MAX630, there are no power spikes or glitches during power transfer.The MAX630’s low-battery detector monitors the line-powered +5V, and the LBD output can be used to shut down unnecessary sections of the system during power failures. Alternatively, the low-battery detector could monitor the NiCad battery voltage and provide warning of power loss when the battery is nearly discharged.Unlike battery backup systems that use 9V batteries,this circuit does not need +12V or +15V to recharge the battery. Consequently, it can be used to provide +5V backup on modules or circuit cards that only have 5V available.9V Battery Life ExtenderFigure 7’s circuit provides a minimum of 7V until the 9V battery voltage falls to less than 2V. When the battery voltage is above 7V, the MAX630’s I C pin is low, putting it into the shutdown mode that draws only 10nA. When the battery voltage falls to 7V, the MAX8212 voltage detector’s output goes high, enabling the MAX630. The MAX630 then maintains the output voltage at 7V, even as the battery voltage falls below 7V. The LBD is used to decrease the oscillator frequency when the battery voltage falls to 3V, thereby increasing the output cur-rent capability of the circuit.CMOS Micropower Step-Up Switching Regulator 10______________________________________________________________________________________Figure 4. High-Power 3V to 5V Converter with ShutdownNote that this circuit (with or without the MAX8212) can be used to provide 5V from four alkaline cells. The initial volt-age is approximately 6V, and the output is maintained at 5V even when the battery voltage falls to less than 2V.Dual-Tracking RegulatorA MAX634 inverting regulator is combined with a MAX630 in F igure 8 to provide a dual-tracking ±15Voutput from a 9V battery. The reference for the -15V output is derived from the positive output through R3and R4. Both regulators are set to maximize output power at low-battery voltage by reducing the oscillator frequency, through LBR, when V BATT falls to 7.2V.MAX630/MAX4193Switching Regulator______________________________________________________________________________________11Figure 5. 3V to 5V Converter with Low-Battery Frequency ShiftFigure 7. Battery Life Extension Down to 3V InFigure 6. Uninterruptable +5V SupplyM A X 630/M A X 4193Switching Regulator 12______________________________________________________________________________________Table 2. Maxim DC-DC ConvertersFigure 8. ±12V Dual-Tracking RegulatorMAX630/MAX4193Switching Regulator______________________________________________________________________________________13Package InformationFor the latest package outline information, go to /packages .Chip TopographyLBR17I CV FB6230.089"(2.26mm)C XL XM A X 630/M A X 4193Switching Regulator Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.14____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600©2008 Maxim Integrated Productsis a registered trademark of Maxim Integrated Products, Inc.Revision History。
MAX9635中文资料
16-BIT ADC
Байду номын сангаас
6-BIT RANGE DIGITAL
CDR, TIM
SIGNAL
CONTROL PROCESSING
16-BIT ADC
方框图
VCC
SDA SCL I2C AO INT
N
GND
________________________________________________________________ Maxim Integrated Products 1 本文是英文数据资料的译文，文中可能存在翻译上的不准确或错误。如需进一步确认，请在您的设计中参考英文资料。
平板PC/笔记本电脑 TV/投影仪/显示器
数字照明管理 便携设备
蜂窝电话/智能电话
安全系统
应用
业内功耗最低的 环境光传感器，内置ADC
特性
♦♦0.045流明至188,000流明宽检测范围 ♦♦小尺寸、2mm x 2mm x 0.6mm UTDFN-Opto封装 ♦♦VCC = 1.7V至3.6V ♦♦工作电流ICC = 0.65µA ♦♦-40°C至+85°C工作温度范围
由于能够检测极其微弱的光线，非常适合光线较暗的工作 环境。
片上光电二极管的光谱响应针对人眼对环境光的响应进行优 化，集成红外及紫外线屏蔽功能。自适应增益电路可自动选
择正确的流明范围优化测试(计数值 / 流明)。
IC设计工作在1.7V至3.6V供电范围，满负荷工作时仅 消 耗0.65µA电流。器件采用小尺寸2mm x 2mm x 0.6mm UTDFN-Opto封装。
有关价格、供货及订购信息，请联络Maxim亚洲销售中心：10800 852 1249 (北中国区)，10800 152 1249 (南中国区)， 或访问Maxim的中文网站：。
MAX4080SASA-T中文资料
General DescriptionThe MAX4080/MAX4081 are high-side, current-sense amplifiers with an input voltage range that extends from 4.5V to 76V making them ideal for telecom, automotive,backplane, and other systems where high-voltage cur-rent monitoring is critical. The MAX4080 is designed for unidirectional current-sense applications and the MAX4081 allows bidirectional current sensing. The MAX4081 single output pin continuously monitors the transition from charge to discharge and avoids the need for a separate polarity output. The MAX4081requires an external reference to set the zero-current output level (V SENSE = 0V). The charging current is rep-resented by an output voltage from V REF to V CC , while discharge current is given from V REF to GND.For maximum versatility, the 76V input voltage range applies independently to both supply voltage (V CC )and common-mode input voltage (V RS+). H igh-side current monitoring does not interfere with the ground path of the load being measured, making the MAX4080/MAX4081 particularly useful in a wide range of high-voltage systems.The combination of three gain versions (5V/V, 20V/V,60V/V = F, T, S suffix) and a user-selectable, external sense resistor sets the full-scale current reading and its proportional output voltage. The MAX4080/MAX4081offer a high level of integration, resulting in a simple,accurate, and compact current-sense solution.The MAX4080/MAX4081 operate from a 4.5V to 76V sin-gle supply and draw only 75µA of supply current. These devices are specified over the automotive operating temperature range (-40°C to +125°C) and are available in a space-saving 8-pin µMAX or SO package.ApplicationsAutomotive (12V, 24V, or 42V Batteries)48V Telecom and Backplane Current MeasurementBidirectional Motor Control Power-Management SystemsAvalanche Photodiode and PIN-Diode Current MonitoringGeneral System/Board-Level Current Sensing Precision High-Voltage Current SourcesFeatures♦Wide 4.5V to 76V Input Common-Mode Range ♦Bidirectional or Unidirectional I SENSE ♦Low-Cost, Compact, Current-Sense Solution ♦Three Gain Versions Available5V/V (MAX4080F/MAX4081F)20V/V (MAX4080T/MAX4081T)60V/V (MAX4080S/MAX4081S)♦±0.1% Full-Scale Accuracy ♦Low 100µV Input Offset Voltage ♦Independent Operating Supply Voltage ♦75µA Supply Current (MAX4080)♦Reference Input for Bidirectional OUT (MAX4081)♦Available in a Space-Saving 8-Pin µMAX PackageMAX4080/MAX408176VVoltage Output________________________________________________________________Maxim Integrated Products 1Pin ConfigurationsOrdering Information19-2562; Rev 0; 10/02For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,or visit Maxim’s website at .Selector Guide appears at end of data sheet.M A X 4080/M A X 408176V , High-Side, Current-Sense Amplifiers with Voltage Output 2_______________________________________________________________________________________ABSOLUTE MAXIMUM RATINGSStresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.V CC to GND............................................................-0.3V to +80V RS+, RS- to GND....................................................-0.3V to +80V OUT to GND.............-0.3V to the lesser of +18V or (V CC + 0.3V)REF1A, REF1B to GND(MAX4081 Only)....-0.3V to the lesser of +18V or (V CC + 0.3V)Output Short Circuit to GND.......................................Continuous Differential Input Voltage (V RS + - V RS -)...............................±80V Current into Any Pin..........................................................±20mAContinuous Power Dissipation (T A = +70°C)8-Pin µMAX (derate 4.5mW/°C above +70°C).............362mW 8-Pin SO (derate 5.88mW/°C above +70°C)................471mW Operating Temperature Range .........................-40°C to +125°C Junction Temperature......................................................+150°C Storage Temperature Range.............................-65°C to +150°C Lead Temperature (soldering, 10s).................................+300°CDC ELECTRICAL CHARACTERISTICSMAX4080/MAX408176V , High-Side, Current-Sense Amplifiers withVoltage Output_______________________________________________________________________________________3DC ELECTRICAL CHARACTERISTICS (continued)M A X 4080/M A X 408176V , High-Side, Current-Sense Amplifiers with Voltage Output 4_______________________________________________________________________________________AC ELECTRICAL CHARACTERISTICSNote 2:V REF is defined as the average voltage of V REF1A and V REF1B . REF1B is usually connected to REF1A or GND.V SENSE is defined as V RS+- V RS-.Note 3:The common-mode range at the low end of 4.5V applies to the most positive potential at RS+ or RS-. Depending on thepolarity of V SENSE and the device’s gain, either RS+ or RS- can extend below 4.5V by the device’s typical full-scale value of V SENSE .Note 4:Negative V SENSE applies to MAX4081 only.Note 5:V SENSE is:MAX4080F, 10mV to 1000mV MAX4080T, 10mV to 250mV MAX4080S, 10mV to 100mV MAX4081F, -500mV to +500mV MAX4081T, -125mV to +125mV MAX4081S, -50mV to +50mVNote 6:V OS is extrapolated from the gain accuracy test for the MAX4080 and measured as (V OUT - V REF )/A V at V SENSE = 0V, for theMAX4081.Note 7:V SENSE is:MAX4080F, 500mV MAX4080T, 125mV MAX4080S, 50mV MAX4081F/T/S, 0VV REF1B = V REF1A = 2.5VNote 8:Output voltage is internally clamped not to exceed 18V.Note 9:Output settles to within 1% of final value.Note 10:The device will not experience phase reversal when overdriven.MAX4080/MAX408176V , High-Side, Current-Sense Amplifiers withVoltage Output_______________________________________________________________________________________52015105302535-125-75-50-25-1000255075100125INPUT OFFSET VOLTAGE HISTOGRAMINPUT OFFSET VOLTAGE (μV)P E R C E N T A G E (%)INPUT OFFSET VOLTAGE vs. TEMPERATURE-300-250-150-200050-50-100300100150200250I N P U T O F F S E T V O L T A G E (μV )-502550-2575100125150TEMPERATURE (°C)-0.5-0.2-0.3-0.40-0.10.40.30.20.10.5-50-250255075100125GAIN ACCURACY vs. TEMPERATURETEMPERATURE (°C)G A I N A C C U R A C Y (%)GAIN ACCURACY vs. V CCV CC (V)G A I N A C C U R A C Y (%)6452402816-0.15-0.10-0.05-0.20476M A X 4080 t o c 05FREQUENCY (Hz)C O M M O N -M ODE R E J E C T I O N R A T I O (d B )100k10k1k10010-120-100-110-90-80-60-70-50-40-20-30-100-13011M MAX4081F/T/SCOMMON-MODE REJECTION RATIOvs. FREQUENCYM A X 080 t o c 06FREQUENCY (Hz)P O W E R -S U P P L Y R E J E C T I O N R A T I O (d B )100k 10k 1k 10010-120-100-110-90-80-60-70-50-40-20-30-100-13011MMAX4081F/T/SPOWER-SUPPLY REJECTION RATIOvs. FREQUENCYM A X 4080 t o c 07FREQUENCY (Hz)R E F E R E N C E R E J E C T I O N R A T I O (dB )-110-90-100-80-60-70-50-40-20-30-100-120MAX4081F/T/SREFERENCE REJECTION RATIOvs. FREQUENCY10k1k100101100k FREQUENCY (kHz)G A I N (d B )100101510152025303540455000.11000MAX4080F/T/SSMALL-SIGNAL GAIN vs. FREQUENCYFREQUENCY (kHz)G A I N (d B )10010151015202530354045500.11000MAX4081F/T/SSMALL-SIGNAL GAIN vs. FREQUENCYTypical Operating Characteristics(V CC = V RS+= 48V, V SENSE = 0V, C LOAD = 20pF, R LOAD = ∞, T A = +25°C, unless otherwise noted.)M A X 4080/M A X 408176V , High-Side, Current-Sense Amplifiers with Voltage Output 6_______________________________________________________________________________________Typical Operating Characteristics (continued)(V CC = V RS+= 48V, V SENSE = 0V, C LOAD = 20pF, R LOAD = ∞, T A = +25°C, unless otherwise noted.)6065757080854281640526476MAX4080SUPPLY CURRENT vs. V CCV CC (V)S U P P L Y C U R R E N T (μA )V CC (V)S U P P L Y C U R R E N T (μA )6452162840859095100105110115120125476MAX4081SUPPLY CURRENT vs. V CC65807570908511010510095115-50-250255075100125MAX4080SUPPLY CURRENT vs. TEMPERATUREM A X 4080 t o c 12TEMPERATURE (°C)S U P P L Y C U R RE N T (μA )65807570908511010510095115-50-250255075100125MAX4081SUPPLY CURRENT vs. TEMPERATURETEMPERATURE (°C)S U P P L Y C U R R E N T (μA )I OUT (SOURCING) (mA)V O U T H I G H V O L T A G E (V C C - V O H ) (V )0.90.80.60.70.20.30.40.50.10.050.100.150.200.250.300.350.400.450.5001.0V OUT HIGH VOLTAGE vs. I OUT (SOURCING)450400350300250200150100505010015020025030000500V OUT LOW VOLTAGE vs. I OUT (SINKING)I OUT (SINKING) (μA)V O U T L O W V O L T A G E (m V )MAX4080 toc16INPUT 5mV/div OUTPUT 25mV/div 20μs/div MAX4080FSMALL-SIGNAL TRANSIENT RESPONSEMAX4080 toc17INPUT 5mV/div OUTPUT 100mV/div 20μs/div MAX4080TSMALL-SIGNAL TRANSIENT RESPONSEMAX4080 toc18INPUT 5mV/divOUTPUT 300mV/div20μs/divMAX4080SSMALL-SIGNAL TRANSIENT RESPONSEMAX4080/MAX408176V , High-Side, Current-Sense Amplifiers withVoltage Output_______________________________________________________________________________________7MAX4080 toc19INPUT 10mV/div OUTPUT 50mV/div 20μs/div MAX4081FSMALL-SIGNAL TRANSIENT RESPONSEMAX4080 toc20INPUT 2.5mV/div OUTPUT 50mV/div 20μs/div MAX4081TSMALL-SIGNAL TRANSIENT RESPONSEMAX4080 toc21INPUT 1mV/divOUTPUT 50mV/div20μs/divMAX4081SSMALL-SIGNAL TRANSIENT RESPONSEMAX4080 toc22INPUT 400mV/div OUTPUT 2V/div 20μs/div MAX4080FLARGE-SIGNAL TRANSIENT RESPONSEMAX4080 toc23INPUT 100mV/div OUTPUT 2V/div 20μs/div MAX4080TLARGE-SIGNAL TRANSIENT RESPONSEMAX4080 toc24INPUT 33mV/divOUTPUT 2V/div20μs/divMAX4080SLARGE-SIGNAL TRANSIENT RESPONSEMAX4080 toc25INPUT 400mV/div OUTPUT 2V/div 20μs/div MAX4081FLARGE-SIGNAL TRANSIENT RESPONSEMAX4080 toc26INPUT 100mV/div OUTPUT 2V/div 20μs/div MAX4081TLARGE-SIGNAL TRANSIENT RESPONSEMAX4080 toc27INPUT 33mV/divOUTPUT 2V/div20μs/divMAX4081SLARGE-SIGNAL TRANSIENT RESPONSETypical Operating Characteristics (continued)(V CC = V RS+= 48V, V SENSE = 0V, C LOAD = 20pF, R LOAD = ∞, T A = +25°C, unless otherwise noted.)M A X 4080/M A X 408176V , High-Side, Current-Sense Amplifiers with Voltage Output 8_______________________________________________________________________________________Typical Operating Characteristics (continued)(V CC = V RS+= 48V, V SENSE = 0V, C LOAD = 20pF, R LOAD = ∞, T A = +25°C, unless otherwise noted.)4μs/div V CC -TRANSIENT RESPONSEV CC 5V/divV OUT 1V/divV RS+ = 20V V CC = 20V STEP V REF1 = V REF2 = 2.5VV CC = 40VV CC = 20VMAX4080 toc29INPUT 500mV/divOUTPUT 2V/div 20μs/div MAX4080FSATURATION RECOVERY RESPONSE(V CC = 4.5V)MAX4080 toc30V CC (0 TO 10V)5V/divOUTPUT 2.5V/div100μs/divMAX4080T STARTUP DELAY (V SENSE = 250mV)Detailed DescriptionThe MAX4080/MAX4081 unidirectional and bidirectional high-side, current-sense amplifiers feature a 4.5V to 76V input common-mode range that is independent of supply voltage. This feature allows the monitoring of current out of a battery as low as 4.5V and also enables high-side current sensing at voltages greater than the supply voltage (V CC ). The MAX4080/MAX4081 monitors current through a current-sense resistor and amplifies the voltage across the resistor. The MAX4080 senses current unidirectionally, while the MAX4081 senses cur-rent bidirectionally.The 76V input voltage range of the MAX4080/MAX4081applies independently to both supply voltage (V CC )and common-mode, input-sense voltage (V RS+). High-side current monitoring does not interfere with the ground path of the load being measured, making the MAX4080/MAX4081 particularly useful in a wide range of high-voltage systems.Battery-powered systems require a precise bidirectional current-sense amplifier to accurately monitor the bat-tery’s charge and discharge. The MAX4081 charging current is represented by an output voltage from V REF to V CC , while discharge current is given from V REF to GND. Measurements of OUT with respect to V REF yield a positive and negative voltage during charge and dis-charge, as illustrated in Figure 1 for the MAX4081T.Current MonitoringThe MAX4080 operates as follows: current from the source flows through R SENSE to the load (Figure 2), cre-ating a sense voltage, V SENSE . Since the internal-sense amplifier’s inverting input has high impedance, negligible current flows through RG2 (neglecting the input bias current). Therefore, the sense amplifier’s inverting input voltage equals V SOURCE - (I LOAD )(R SENSE ). The ampli-fier’s open-loop gain forces its noninverting input to the same voltage as the inverting input. Therefore, the drop across RG1 equals V SENSE . The internal current mirror multiplies I RG1by a current gain factor, β, to give I A2= β✕IRG1. Amplifier A2 is used to convert the output current to a voltage and then sent through amplifier A3.Total gain = 5V/V for MAX4080F, 20V/V for the MAX4080T, and 60V/V for the MAX4080S.The MAX4081 input stage differs slightly from the MAX4080 (Figure 3). Its topology allows for monitoring of bidirectional currents through the sense resistor.When current flows from RS+ to RS-, the MAX4081matches the voltage drop across the external sense resistor, R SENSE , by increasing the current through the Q1 and RG1. In this way, the voltages at the input ter-minals of the internal amplifier A1 are kept constant and an accurate measurement of the sense voltage is achieved. In the following amplifier stages of the MAX4081, the output signal of amplifier A2 is level-shifted to the reference voltage (V REF = V REF1A =V REF1B ), resulting in a voltage at the output pin (OUT)MAX4080/MAX408176V , High-Side, Current-Sense Amplifiers withVoltage Output_______________________________________________________________________________________9Pin DescriptionM A X 4080/M A X 4081that swings above V REF voltage for positive-sense volt-ages and below V REF for negative-sense voltages.V OUT is equal to V REF when V SENSE is equal to zero.Set the full-scale output range by selecting R SENSE and the appropriate gain version of the MAX4080/MAX4081.76V , High-Side, Current-Sense Amplifiers with Voltage Output 10______________________________________________________________________________________Figure 1. MAX4081T OUT Transfer CurveFigure 3. MAX4081 Functional DiagramFigure 2. MAX4080 Functional DiagramMAX4080/MAX408176V , High-Side, Current-Sense Amplifiers withVoltage Output______________________________________________________________________________________11For the bidirectional MAX4081, the V OUT reference level is controlled by REF1A and REF1B. V REF is defined as the average voltage of V REF1A and V REF1B . Connect REF1A and REF1B to a low-noise, regulated voltage source to set the output reference level. In this mode,V OUT equals V REF1A when V SENSE equals zero (see Figure 4).Alternatively, connect REF1B to ground, and REF1A to a low-noise, regulated voltage source. In this case, the out-put reference level (V REF ) is equal to V REF1A divided by two. V OUT equals V REF1A /2 when V SENSE equals zero.In either mode, the output swings above the reference voltage for positive current-sensing (V RS+> V RS-). The output swings below the reference voltage for negative current-sensing (V RS+< V RS-).Recommended Component ValuesIdeally, the maximum load current develops the full-scale sense voltage across the current-sense resistor.Choose the gain needed to yield the maximum output voltage required for the application:V OUT = V SENSE ✕A Vwhere V SENSE is the full-scale sense voltage, 1000mV for gain of 5V/V, 250mV for gain of 20V/V, 100mV for gain of 60V/V, and A V is the gain of the device.In applications monitoring a high current, ensure that R SENSE is able to dissipate its own I 2R loss. If the resis-tor’s power dissipation is exceeded, its value may drift or it may fail altogether.The MAX4080/MAX4081 sense a wide variety of cur-rents with different sense-resistor values. Table 1 lists common resistor values for typical operation.M A X 4080/M A X 4081The full-scale output voltage is V OUT = R SENSE ✕I LOAD (MAX)✕A V , for the MAX4080 and V OUT = V REF ±R SENSE ✕ I LOAD(MAX)✕ A V for the MAX4081.V SENSE(MAX)is 1000mV for the 5V/V gain version,250mV for the 20V/V gain version, and 100mV for the 60V/V gain version.Choosing the Sense ResistorChoose R SENSE based on the following criteria:•Voltage Loss:A high R SENSE value causes the power-source voltage to degrade through IR loss. For minimal voltage loss, use the lowest R SENSE value.•Accuracy:A high R SENSE value allows lower cur-rents to be measured more accurately. This is due to offsets becoming less significant when the sense voltage is larger. For best performance, select R SENSE to provide approximately 1000mV (gain of 5V/V), 250mV (gain of 20V/V), or 100mV (gain of 60V/V) of sense voltage for the full-scale current in each application.•Efficiency and Power Dissipation:At high current levels, the I 2R losses in R SENSE can be significant.Take this into consideration when choosing the resistor value and its power dissipation (wattage)rating. Also, the sense resistor’s value might drift if it is allowed to heat up excessively.•Inductance:Keep inductance low if I SENSE has a large high-frequency component. Wire-wound resis-tors have the highest inductance, while metal film is somewhat better. Low-inductance, metal-film resis-tors are also available. Instead of being spiral-wrapped around a core, as in metal-film or wire-wound resistors, they are a straight band of metal and are available in values under 1Ω.Because of the high currents that flow through R SENSE ,take care to eliminate parasitic trace resistance from causing errors in the sense voltage. Either use a four-terminal current-sense resistor or use Kelvin (force and sense) PC board layout techniques.Dynamic Range ConsiderationAlthough the MAX4081 have fully symmetrical bidirec-tional V SENSE input capability, the output voltage range is usually higher from REF to V CC and lower from REF to GND (unless the supply voltage is at the lowest end of the operating range). Therefore, the user must con-sider the dynamic range of current monitored in both directions and choose the supply voltage and the refer-ence voltage (REF) to make sure the output swing above and below REF is adequate to handle the swings without clipping or running out of headroom.Power-Supply Bypassing and GroundingFor most applications, bypass V CC to GND with a 0.1µF ceramic capacitor. In many applications, V CC can be connected to one of the current monitor terminals (RS+or RS-). Because V CC is independent of the monitored voltage, V CC can be connected to a separate regulated supply.If V CC will be subject to fast-line transients, a series resistor can be added to the power-supply line of the MAX4080/MAX4081 to minimize output disturbance.This resistance and the decoupling capacitor reduce the rise time of the transient. For most applications, 1k Ωin conjunction with a 0.1µF bypass capacitor work well.The MAX4080/MAX4081 require no special considera-tions with respect to layout or grounding. Consideration should be given to minimizing errors due to the large charge and discharge currents in the system.76V , High-Side, Current-Sense Amplifiers with Voltage Output 12______________________________________________________________________________________Figure 4. MAX4081 Reference InputsPower ManagementThe bidirectional capability of the MAX4081 makes it an excellent candidate for use in smart battery packs. In the application diagram (Figure 5), the MAX4081 moni-tors the charging current into the battery as well as the discharge current out of the battery. The microcon-troller stores this information, allowing the system to query the battery's status as needed to make system power-management decisions.MAX4080/MAX408176V , High-Side, Current-Sense Amplifiers withVoltage Output______________________________________________________________________________________13Typical Operating CircuitChip InformationTRANSISTOR COUNT: 185PROCESS: BipolarFigure 5. MAX4081 Used In Smart-Battery ApplicationM A X 4080/M A X 408176V , High-Side, Current-Sense Amplifiers with Voltage Output 14______________________________________________________________________________________Package Information(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,go to /packages .)MAX4080/MAX408176V , High-Side, Current-Sense Amplifiers withVoltage OutputMaxim cannot assume responsib ility for use of any circuitry other than circuitry entirely emb odied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________15©2002 Maxim Integrated Productsis a registered trademark of Maxim Integrated Products.Package Information (continued)(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,go to /packages .)。
MAX6381XR44D5资料
General Description The MAX6381–MAX6390 microprocessor (µP) supervisory circuits monitor power-supply voltages from +1.8V to +5.0V while consuming only 3µA of supply current at +1.8V. Whenever V CC falls below the factory-set reset thresholds, the reset output asserts and remains assert-ed for a minimum reset timeout period after V CC rises above the reset threshold. Reset thresholds are available from +1.58V to +4.63V, in approximately 100mV incre-ments. Seven minimum reset timeout delays ranging from 1ms to 1200ms are available.The MAX6381/MAX6384/MAX6387 have a push-pull active-low reset output. The MAX6382/MAX6385/ MAX6388 have a push-pull active-high reset output, and the MAX6383/MAX6386/MAX6389/MAX6390 have an open-drain active-low reset output. The MAX6384/MAX6385/MAX6386 also feature a debounced manual reset input (with internal pullup resistor). The MAX6387/MAX6388/MAX6389 have an auxiliary input for monitoring a second voltage. The MAX6390 offers a manual reset input with a longer V CC reset timeout period (1120ms or 1200ms) and a shorter manual reset timeout (140ms or 150ms).The MAX6381/MAX6382/MAX6383 are available in 3-pin SC70 and6-pinµDFN packages and the MAX6384–MAX6390 are available in 4-pin SC70 andFeatures♦Factory-Set Reset Threshold Voltages Rangingfrom +1.58V to +4.63V in Approximately 100mVIncrements♦±2.5% Reset Threshold Accuracy OverTemperature (-40°C to +125°C)♦Seven Reset Timeout Periods Available: 1ms,20ms, 140ms, 280ms, 560ms, 1120ms,1200ms (min)♦3 Reset Output OptionsActive-Low Push-PullActive-High Push-PullActive-Low Open-Drain♦Reset Output State Guaranteed ValidDown to V CC= 1V♦Manual Reset Input (MAX6384/MAX6385/MAX6386)♦Auxiliary RESET IN(MAX6387/MAX6388/MAX6389)♦V CC Reset Timeout (1120ms or 1200ms)/ManualReset Timeout (140ms or 150ms) (MAX6390)♦Negative-Going V CC Transient Immunity♦Low Power Consumption of 6µA at +3.6Vand 3µA at +1.8V♦Pin Compatible withMAX809/MAX810/MAX803/MAX6326/MAX6327/MAX6328/MAX6346/MAX6347/MAX6348,and MAX6711/MAX6712/MAX6713♦Tiny 3-Pin/4-Pin SC70 and 6-Pin µDFN PackagesMAX6381–MAX6390 SC70/µDFN, Single/Dual Low-Voltage,Low-Power µP Reset Circuits ________________________________________________________________Maxim Integrated Products1Pin Configurations19-1839; Rev 4; 4/07Ordering InformationOrdering Information continued at end of data sheet.Typi cal Operati ng Ci rcui t appears at end of data sheet.Selector Guide appears at end of data sheet.after "XR", "XS", or "LT." Insert reset timeout delay (see ResetTimeout Delay table) after "D" to complete the part number.Sample stock is generally held on standard versions only (seeStandard Versions table). Standard versions have an orderincrement requirement of 2500 pieces. Nonstandard versionshave an order increment requirement of 10,000 pieces.Contact factory for availability of nonstandard versions.+Denotes a lead-free package.For pricing, delivery, and ordering information,please contact Maxim Direct at 1-888-629-4642,or visit Maxim’s website at .ComputersControllersIntelligent InstrumentsCritical µP and µCPower MonitoringPortable/Battery-Powered EquipmentDual Voltage SystemsM A X 6381–M A X 6390SC70/µDFN, Single/Dual Low-Voltage, Low-Power µP Reset CircuitsABSOLUTE MAXIMUM RATINGSELECTRICAL CHARACTERISTICS(V CC = full range, T A = -40°C to +125°C, unless otherwise specified. Typical values are at T A = +25°C.) (Note 1)Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.V CC to GND..........................................................-0.3V to +6.0V RESET Open-Drain Output....................................-0.3V to +6.0V RESET , RESET (push-pull output)..............-0.3V to (V CC + 0.3V)MR , RESET IN.............................................-0.3V to (V CC + 0.3V)Input Current (V CC ).............................................................20mA Output Current (all pins).....................................................20mAContinuous Power Dissipation (T A = +70°C)3-Pin SC70 (derate 2.9mW/°C above +70°C)..............235mW 4-Pin SC70 (derate 3.1mW/°C above +70°C)..............245mW 6-Pin µDFN (derate 2.1mW/°C above +70°C)..........167.7mW Operating Temperature Range .........................-40°C to +125°C Storage Temperature Range.............................-65°C to +150°C Lead Temperature (soldering, 10s).................................+300°CMAX6381–MAX6390SC70/µDFN, Single/Dual Low-Voltage,Low-Power µP Reset Circuits_______________________________________________________________________________________3M A X 6381–M A X 6390SC70/µDFN, Single/Dual Low-Voltage, Low-Power µP Reset Circuits 4______________________________________________________________________________________Typical Operating Characteristics(T A = +25°C, unless otherwise noted.)215436789-40-105-25203550658095110125SUPPLY CURRENT vs. TEMPERATURE(NO LOAD)TEMPERATURE (°C)S U P P L Y C U R R E N T (µA )25292735333137394143-40-105-25203550658095110125POWER-DOWN RESET DELAYvs. TEMPERATURETEMPERATURE (°C)P O W E R -D O W N R E S E T D E L A Y (µs )0.940.980.961.021.001.061.041.08-40-10520-253550658095110125NORMALIZED POWER-UP RESET TIMEOUTvs. TEMPERATUREM A X 6381/90 t o c 03TEMPERATURE (°C)N O R M A L I Z E D R E S E T T I M E O U T P E R I O D0.9900.9851.0150.9950.9901.0001.0051.0101.020-40-10520-253550958011065125M A X 6381/90 t o c 04TEMPERATURE (°C)N O R M A L I Z E D R E S E T TH R E S H O L D NORMALIZED RESET THRESHOLDvs. TEMPERATURE00.40.20.80.61.01.2063912OUTPUT-VOLTAGE LOW vs. SINK CURRENTI SINK (mA)V O L (V )01.00.52.01.52.53.00500750250100012501500OUTPUT-VOLTAGE HIGH vs. SOURCE CURRENTI SOURCE (µA)V O H (V )45001100010010MAXIMUM TRANSIENT DURATION vs. RESET COMPARATOR OVERDRIVE15050350250500200100400300RESET COMPARATOR OVERDRIVE, V TH - V CC (mV)M A X I M U M T R A N S I E N T D U R A T I O N (µs )3.53.93.74.54.34.14.74.95.35.15.5-40-105-25203550658095110125RESET IN TO RESET DELAYvs. TEMPERATUREM A X 6381/90 t o c 08TEMPERATURE (°C)R E S E T I N D E L A Y (µs )MAX6381–MAX6390SC70/µDFN, Single/Dual Low-Voltage,Low-Power µP Reset CircuitsPin DescriptionM A X 6381–M A X 6390SC70/µDFN, Single/Dual Low-Voltage, Low-Power µP Reset Circuits 6_______________________________________________________________________________________Detailed DescriptionRESET OutputA µP reset input starts the µP in a known state. These µP supervisory circuits assert reset to prevent code execution errors during power-up, power-down, or brownout conditions.Reset asserts when V CC is below the reset threshold;once V CC exceeds the reset threshold, an internal timer keeps the reset output asserted for the reset timeout period. After this interval, reset output deasserts. Reset output is guaranteed to be in the correct logic state for V CC ≥1V.Manual Reset Input (MAX6384/MAX6385/MAX6386/MAX6390)Many µP-based products require manual reset capabil-ity, allowing the operator, a test technician, or external logic circuitry to initiate a reset. A logic low on MR asserts reset. Reset remains asserted while MR is low,and for the reset active timeout period (t RP ) after MR returns high. This input has an internal 63k Ωpullup resistor (1.56k Ωfor MAX6390), so it can be left uncon-nected if it is not used. MR can be driven with TTL or CMOS logic levels, or with open-drain/collector outputs.Connect a normally open momentary switch from MR to G ND to create a manual-reset function; external debounce circuitry is not required. If MR is driven from long cables or if the device is used in a noisy environ-ment, connecting a 0.1µF capacitor from MR to G ND provides additional noise immunity.RESET IN Comparator(MAX6387/MAX6388/MAX6389)RESET IN is compared to an internal +1.27V reference.If the voltage at RESET IN is less than 1.27V, reset asserts. Use the RESET IN comparator as a user-adjustable reset detector or as a secondary power-sup-ply monitor by implementing a resistor-divider at RESET IN (shown in Figure 1). Reset asserts when either V CC or RESET IN falls below its respective threshold volt-age. Use the following equation to set the threshold:V INTH = V THRST (R1/R2 + 1)where V THRST = +1.27V. To simplify the resistor selec-tion, choose a value of R2 and calculate R1:R1 = R2 [(V INTH /V THRST ) - 1]Since the input current at RESET IN is 50nA (max),large values can be used for R2 with no significant loss in accuracy.___________Applications InformationNegative-Going V CC TransientsIn addition to issuing a reset to the µP during power-up,power-down, and brownout conditions, the MAX6381–MAX6390 are relatively immune to short dura-tion negative-going V CC transients (glitches).The Typical Operating Characteristics section shows the Maximum Transient Durations vs. Reset Comparator Overdrive, for which the MAX6381–MAX6390 do not generate a reset pulse. This graph was generated usinga negative-going pulse applied to V CC , starting above the actual reset threshold and ending below it by the magnitude indicated (reset comparator overdrive). The graph indicates the typical maximum pulse width a neg-ative-going V CC transient may have without causing a reset pulse to be issued. As the magnitude of the tran-sient increases (goes farther below the reset threshold),the maximum allowable pulse width decreases. A 0.1µF capacitor mounted as close as possible to V CC provides additional transient immunity.Ensuring a Valid RESET Output Down to V CC = 0VThe MAX6381–MAX6390 are guaranteed to operate properly down to V CC = 1V. In applications that require valid reset levels down to V CC = 0V, a pulldown resistor to active-low outputs (push/pull only, Figure 2) and a pullup resistor to active-high outputs (push/pull only)will ensure that the reset line is valid while the reset out-put can no longer sink or source current. This schemedoes not work with the open-drain outputs of the MAX6383/MAX6386/MAX6389/MAX6390. The resistor value used is not critical, but it must be small enough not to load the reset output when V CC is above the reset threshold. For most applications, 100k Ωis ade-quate.MAX6381–MAX6390SC70/µDFN, Single/Dual Low-Voltage,Low-Power µP Reset Circuits_______________________________________________________________________________________7M A X 6381–M A X 6390SC70/µDFN, Single/Dual Low-Voltage, Low-Power µP Reset Circuits 8_______________________________________________________________________________________Selector GuideOrdering Information (continued)Note:Insert reset threshold suffix (see Reset Threshold table)after "XR", "XS", or "LT." Insert reset timeout delay (see Reset Timeout Delay table) after "D" to complete the part number.Sample stock is generally held on standard versions only (see Standard Versions table). Standard versions have an order increment requirement of 2500 pieces. Nonstandard versions have an order increment requirement of 10,000 pieces.Contact factory for availability of nonstandard versions.*MAX6390 is available with D4 or D7 timing only.+Denotes a lead-free package.MAX6381–MAX6390SC70/µDFN, Single/Dual Low-Voltage,Low-Power µP Reset Circuits_______________________________________________________________________________________9Chip InformationTRANSISTOR COUNT: 647PROCESS: BiCMOSPin Configurations (continued)M A X 6381–M A X 6390SC70/µDFN, Single/Dual Low-Voltage, Low-Power µP Reset Circuits 10______________________________________________________________________________________Package Information(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,go to /packages .)MAX6381–MAX6390SC70/µDFN, Single/Dual Low-Voltage,Low-Power µP Reset Circuits______________________________________________________________________________________11Package Information (continued)(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,go to /packages .)M A X 6381–M A X 6390SC70/µDFN, Single/Dual Low-Voltage, Low-Power µP Reset Circuits 12______________________________________________________________________________________Package Information (continued)(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,go to /packages .)SC70/µDFN, Single/Dual Low-Voltage,Low-Power µP Reset CircuitsMaxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600____________________13©2007 Maxim Integrated Productsis a registered trademark of Maxim Integrated Products, Inc.MAX6381–MAX6390Package Information (continued)(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,go to /packages .)Revision HistoryPages changed at Rev 4: Title on all pages, 1, 2, 5,7–13。
MAX6314US27D3+中文资料
General DescriptionThe MAX6314 low-power CMOS microprocessor (µP)supervisory circuit is designed to monitor power supplies in µP and digital systems. The MAX6314’s RESET output is bidirectional, allowing it to be directly connected to µPs with bidirectional reset inputs, such as the 68HC11. It provides excellent circuit reliability and low cost by eliminating external components and adjustments. The MAX6314 also provides a debounced manual reset input.This device performs a single function: it asserts a reset signal whenever the V CC supply voltage falls below a preset threshold or whenever manual reset is asserted.Reset remains asserted for an internally programmed interval (reset timeout period) after V CC has risen above the reset threshold or manual reset is deasserted.The MAX6314 comes with factory-trimmed reset threshold voltages in 100mV increments from 2.5V to 5V. Preset timeout periods of 1ms, 20ms, 140ms,and 1120ms (minimum) are also available. The device comes in a SOT143 package.F or a µP supervisor with an open-drain reset pin, see the MAX6315 data sheet.________________________ApplicationsComputers ControllersIntelligent InstrumentsCritical µP and µC Power Monitoring Portable/Battery-Powered EquipmentFeatures♦Small SOT143 Package♦RESET Output Simplifies Interface to Bidirectional Reset I/Os♦Precision Factory-Set V CC Reset Thresholds:100mV Increments from 2.5V to 5V♦±1.8% Reset Threshold Accuracy at T A = +25°C ♦±2.5% Reset Threshold Accuracy Over Temp.♦Four Reset Timeout Periods Available: 1ms, 20ms, 140ms, or 1120ms (minimum) ♦Immune to Short V CC Transients ♦5µA Supply Current♦Pin-Compatible with MAX811MAX6314*68HC11/Bidirectional-CompatibleµP Reset Circuit________________________________________________________________Maxim Integrated Products1Pin ConfigurationTypical Operating Circuit19-1090; Rev 2; 12/05Ordering Information continued at end of data sheet.*Patents PendingFor pricing, delivery, and ordering information,please contact Maxim/Dallas Direct!at 1-888-629-4642, or visit Maxim’s website at .Ordering Information†The MAX6314 is available in a SOT143 package, -40°C to+85°C temperature range.††The first two letters in the package top mark identify the part,while the remaining two letters are the lot tracking code.Devices are available in both leaded and lead-free packaging.Specify lead-free by replacing “-T” with “+T” when ordering.M A X 631468HC11/Bidirectional-Compatible µP Reset Circuit 2_______________________________________________________________________________________ABSOLUTE MAXIMUM RATINGSELECTRICAL CHARACTERISTICS(V CC = +2.5V to +5.5V, T A = -40°C to +85°C, unless otherwise noted. Typical values are at T A = +25°C.)Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.Note 1:The MAX6314 monitors V CC through an internal, factory-trimmed voltage divider that programs the nominal reset threshold.Factory-trimmed reset thresholds are available in 100mV increments from 2.5V to 5V (see Ordering and Marking Information ).Note 2:This is the minimum time RESET must be held low by an external pull-down source to set the active pull-up flip-flop.Note 3:Measured from RESET V OL to (0.8 x V CC ), R LOAD = ∞.V CC ........................................................................-0.3V to +6.0V All Other Pins..............................................-0.3V to (V CC + 0.3V)Input Current (V CC ).............................................................20mA Output Current (RESET )......................................................20mA Rate of Rise (V CC )...........................................................100V/µsContinuous Power Dissipation (T A = +70°C)SOT143 (derate 4mW/°C above +70°C).......................320mW Operating Temperature Range ...........................-40°C to +85°C Storage Temperature Range.............................-65°C to +160°C Lead Temperature (soldering, 10sec).............................+300°CMAX631468HC11/Bidirectional-CompatibleµP Reset Circuit_______________________________________________________________________________________3__________________________________________Typical Operating Characteristics(T A = +25°C, unless otherwise noted.)4.7k Ω PULL-UP 2V/divMAX6314 PULL-UP 2V/divINPUT 5V/div200ns/divPULLUP CHARACTERISTICS100pF4.7k Ω+5V74HC0574HC05V CCGNDMR 100pF+5VRESETMAX63146-50-303090SUPPLY CURRENT vs. TEMPERATURE215TEMPERATURE (°C)S U P P L Y C U R R E N T (µA )-101050347060135SUPPLY CURRENT vs. SUPPLY VOLTAGE215SUPPLY VOLTAGE (V)S U P P L Y C U R R E N T (µA )2344500-50-301090POWER-DOWN RESET DELAYvs. TEMPERATURE1040TEMPERATURE (°C)P O W E R -D O W N R E S E T D E L A Y (µs )-1020303050701.040.96-50-301090NORMALIZED RESET TIMEOUT PERIOD vs. TEMPERATURE (V CC RISING)0.970.981.021.001.03M A X 6314-05TEMPERATURE (°C)N O R M A L I Z E D R E S E T T I M E O U T P E R I O D -100.991.013050701.0060.994-50-301090NORMALIZED RESET THRESHOLD vs. TEMPERATURE (V CC FALLING)0.9960.9981.0041.000M A X 6314-06TEMPERATURE (°C)N O R M A L I Z E D R E S E T T H R E S H O L D-101.0023050701000101001000MAXIMUM TRANSIENT DURATION vs. RESET COMPARATOR OVERDRIVE20RESET COMP. OVERDRIVE, V TH - V CC (mV)M A X I M U M T R A N S I E N T D U R A T I O N (µs )4060806000-50-301090RESET PULLUP TIME vs. TEMPERATURE100200500300TEMPERATURE (°C)R E S E T P U L L -U P -T I M E (n s )-10400305070Figure 1. Functional Diagram M A X 631468HC11/Bidirectional-Compatible µP Reset Circuit 4_____________________________________________________________________________________________________________________________________________________Pin DescriptionSupply Voltage and Reset Threshold Monitor InputV CC4Manual Reset Input. A logic low on MR asserts reset. Reset remains asserted as long as MR is low, and for the reset timeout period (t RP ) after the reset conditions are terminated. Connect to V CC if not used.MR 3PIN Active-Low Complementary Output. In addition to the normal n-channel pulldown, RESET has a p-channel pullup transistor in parallel with a 4.7k Ωresistor to facilitate connection to µPs with bidirectional resets. See the Reset Output section.RESET2GroundGND 1FUNCTIONNAMEMAX631468HC11/Bidirectional-CompatibleµP Reset Circuit_______________________________________________________________________________________5Detailed DescriptionThe MAX6314 has a reset output consisting of a 4.7k Ωpull-up resistor in parallel with a P-channel transistor and an N-channel pull down (Figure 1), allowing this IC to directly interface with microprocessors (µPs) that have bidirectional reset pins (see the Reset Output section).Reset OutputA µP’s reset input starts the µP in a known state. The MAX6314 asserts reset to prevent code-execution errors during power-up, power-down, or brownout conditions. RESET is guaranteed to be a logic low for V CC > 1V (see the Electrical Characteristics table).Once V CC exceeds the reset threshold, the internal timer keeps reset asserted for the reset timeout period (t RP ); after this interval RESET goes high. If a brownout condition occurs (monitored voltage dips below its pro-grammed reset threshold), RESET goes low. Any time V CC dips below the reset threshold, the internal timer resets to zero and RESET goes low. The internal timer starts when V CC returns above the reset threshold, and RESET remains low for the reset timeout period.The MAX6314’s RESET output is designed to interface with µPs that have bidirectional reset pins, such as the Motorola 68HC11. Like an open-drain output, the MAX6314 allows the µP or other devices to pull RESET low and assert a reset condition. However, unlike a standard open-drain output, it includes the commonly specified 4.7k Ωpullup resistor with a P-channel active pullup in parallel.This configuration allows the MAX6314 to solve a prob-lem associated with µPs that have bidirectional reset pins in systems where several devices connect to RESET . These µPs can often determine if a reset was asserted by an external device (i.e., the supervisor IC)or by the µP itself (due to a watchdog fault, clock error,or other source), and then jump to a vector appropriate for the source of the reset. However, if the µP does assert reset, it does not retain the information, but must determine the cause after the reset has occurred.The following procedure describes how this is done with the Motorola 68HC11. In all cases of reset, the µP pulls RESET low for about four E-clock cycles. It then releases RESET , waits for two E-clock cycles, then checks RESET ’s state. If RESET is still low, the µP con-cludes that the source of the reset was external and,when RESET eventually reaches the high state, jumps to the normal reset vector. In this case, stored state information is erased and processing begins fromscratch. If, on the other hand, RESET is high after the two E-clock cycle delay, the processor knows that it caused the reset itself and can jump to a different vec-tor and use stored state information to determine what caused the reset.The problem occurs with faster µPs; two E-clock cycles is only 500ns at 4MHz. When there are several devices on the reset line, the input capacitance and stray capacitance can prevent RESET from reaching the logic-high state (0.8 x V CC ) in the allowed time if only a passive pullup resistor is used. In this case, all resets will be interpreted as external. The µP is guaranteed to sink only 1.6mA, so the rise time cannot be much reduced by decreasing the recommended 4.7k Ωpullup resistance.The MAX6314 solves this problem by including a pullup transistor in parallel with the recommended 4.7k Ωresis-tor (Figure 1). The pullup resistor holds the output high until RESET is forced low by the µP reset I/O, or by the MAX6314 itself. Once RESET goes below 0.5V, a com-parator sets the transition edge flip-flop, indicating that the next transition for RESET will be low to high. As soon as RESET is released, the 4.7k Ωresistor pulls RESET up toward V CC . When RESET rises above 0.5V,the active p-channel pullup turns on for the 2µs duration of the one-shot. The parallel combination of the 4.7k Ωpullup and the p-channel transistor on-resistance quickly charges stray capacitance on the reset line, allowing RESET to transition low to high with-in the required two E-clock period, even with several devices on the reset line (Figure 2). Once the one-shot times out, the p-channel transistor turns off. This process occurs regardless of whether the reset was caused by V CC dipping below the reset threshold, MR being asserted, or the µP or other device asserting RESET . Because the MAX6314 includes the standard 4.7k Ωpullup resistor, no external pullup resistor is required. To minimize current consumption, the internal pullup resistor is disconnected whenever the MAX6314asserts RESET .Manual Reset InputMany µP-based products require manual reset capabil-ity, allowing the operator, a test technician, or external logic circuitry to initiate a reset. A logic low on MR asserts reset. Reset remains asserted while MR is low,and for the reset active timeout period after MR returns high. To minimize current consumption, the internal 4.7k Ωpullup resistor on RESET is disconnected whenever RESET is asserted.M A X 631468HC11/Bidirectional-Compatible µP Reset Circuit 6_______________________________________________________________________________________MR has an internal 63k Ωpullup resistor, so it can be left open if not used. Connect a normally open momen-tary switch from MR to GND to create a manual reset function; external debounce circuitry is not required. If MR is driven from long cables or if the device is used in a noisy environment, connecting a 0.1µF capacitor from MR to ground provides additional noise immunity.__________Applications InformationNegative-Going V CC TransientsIn addition to issuing a reset to the µP during power-up,power-down, and brownout conditions, these devices are relatively immune to short-duration negative-going transients (glitches). The T ypical Operating Character-istics show the Maximum Transient Duration vs. Reset Threshold Overdrive, for which reset pulses are not generated. The graph was produced using negative-going pulses, starting at V RST max and ending below the programmed reset threshold by the magnitude indicated (reset threshold overdrive). The graph shows the maximum pulse width that a negative-going V CC transient may typically have without causing a reset pulse to be issued. As the amplitude of the transient increases (i.e., goes farther below the reset threshold),the maximum allowable pulse width decreases. A 0.1µF bypass capacitor mounted close to V CC provides addi-tional transient immunity.Ensuring a Valid RESET OutputDown to V CC = 0VWhen V CC falls below 1V, RESET no longer sinks current—it becomes an open circuit. Therefore, high-impedance CMOS-logic inputs connected to RESET can drift to undetermined voltages. This presents no problem in most applications, since most µP and other circuitry is inoperative with V CC below 1V. However, in applications where RESET must be valid down to V CC = 0V, adding a pull-down resistor to RESET will cause any stray leakage currents to flow to ground,holding RESET low (Figure 3). R1’s value is not critical;100k Ωis large enough not to load RESET and small enough to pull RESET to ground.Figure 2. MAX6314 Supports Additional Devices on the Reset BusFigure 3. RESET Valid to V CC = Ground CircuitMAX631468HC11/Bidirectional-CompatibleµP Reset Circuit_______________________________________________________________________________________7Figure 4. RESET Timing Diagram†The MAX6314 is available in a SOT143 package, -40°C to +85°C temperature range.††The first two letters in the package top mark identify the part, while the remaining two letters are the lot tracking code.†††Sample stocks generally held on the bolded products; also, the bolded products have 2,500 piece minimum-order quantities.Non-bolded products have 10,000 piece minimum-order quantities. Contact factory for details.Devices are available in both leaded and lead-free packaging. Specify lead-free by replacing “-T” with “+T” when ordering.Note:All devices available in tape-and-reel only. Contact factory for availability.___________________________________________Ordering Information (continued)M A X 631468HC11/Bidirectional-Compatible µP Reset Circuit Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.8_____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600©2005 Maxim Integrated ProductsPrinted USAis a registered trademark of Maxim Integrated Products, Inc._____________________________Ordering and Marking Information (continued)†The MAX6314 is available in a SOT143 package, -40°C to +85°C temperature range.††The first two letters in the package top mark identify the part, while the remaining two letters are the lot tracking code.†††Sample stocks generally held on the bolded products; also, the bolded products have 2,500 piece minimum-order quantities.Non-bolded products have 10,000 piece minimum-order quantities. Contact factory for details.Devices are available in both leaded and lead-free packaging. Specify lead-free by replacing “-T” with “+T” when ordering.Note:All devices available in tape-and-reel only. Contact factory for availability.Chip InformationTRANSISTOR COUNT: 519Package InformationFor the latest package outline information, go to /packages .。
MAX6368LKA29-T中文资料
General DescriptionThe MAX6365–MAX6368 supervisory circuits simplify power-supply monitoring, battery-backup control func-tions, and memory write protection in microprocessor (µP) systems. The circuits significantly improve the size,accuracy, and reliability of modern systems with an ultra-small integrated solution.These devices perform four basic system functions:1) Provide a µP reset output during V CC supply power-up, power-down, and brownout conditions.2) Internally control V CC to backup-battery switching tomaintain data or low-power operation for CMOS RAM, CMOS µPs, real-time clocks, and other digital logic when the main supply fails.3) Provide memory write protection through internalchip-enable gating during supply or processor faults.4) Include one of the following options: a manual resetinput (MAX6365), a watchdog timer function (MAX6366), a battery-on output (MAX6367), or an auxiliary user-adjustable reset input (MAX6368).The MAX6365–MAX6368 operate from V CC supply volt-ages as low as 1.2V. The factory preset reset threshold voltages range from 2.32V to 4.63V (see Ordering Information ). In addition, each part is offered in three reset output versions: push-pull active low, open-drain active low, or open-drain active high (see Selector Guide ). The MAX6365–MAX6368 are available in minia-ture 8-pin SOT23 packages.ApplicationsCritical µP/µC Power Portable/Battery-Monitoring Powered Equipment Fax Machines Set-Top Boxes Industrial Control POS EquipmentComputers/ControllersFeatureso Low +1.2V Operating Supply Voltage (V CC or V BATT )o Precision Monitoring of +5.0V, +3.3V, +3.0V, and +2.5V Power-Supply Voltageso On-Board Gating of Chip-Enable Signals, 1.5ns Propagation Delayo Debounced Manual Reset Input (MAX6365)o Watchdog Timer, 1.6s Timeout (MAX6366)o Battery-On Output Indicator (MAX6367)o Auxiliary User-Adjustable RESET IN (MAX6368)o Low 10µA Quiescent Supply Current o Three Available Output StructuresPush-Pull RESET Open-Drain RESET Open-Drain RESETo RESET/RESET Valid Down to 1.2V Guaranteed (V CC or V BATT )o Power-Supply Transient Immunity o 150ms min Reset Timeout Period o Miniature 8-Pin SOT23 PackageMAX6365–MAX6368SOT23, Low-Power µP Supervisory Circuits with Battery Backup and Chip-Enable Gating________________________________________________________________Maxim Integrated Products1Pin Configurations19-1658; Rev 1; 6/01For pricing, delivery, and ordering information,please contact Maxim/Dallas Direct!at 1-888-629-4642, or visit Maxim’s website at .Ordering Information*These parts offer a choice of reset threshold voltages. From the Reset Threshold Ranges table, insert the desired threshold volt-age code in the blank to complete the part number. SOT parts come in tape-and-reel only and must be ordered in 2500-piece increments. See Device Marking Codes for a complete parts list,including SOT top marks and standard threshold versions. See Selector Guide for a listing of device features.Typical Operating Circuit appears at end of data sheet.M A X 6365–M A X 6368SOT23, Low-Power µP Supervisory Circuits with Battery Backup and Chip-Enable GatingABSOLUTE MAXIMUM RATINGSELECTRICAL CHARACTERISTICS(V = +2.4V to +5.5V, V = +3.0V, CE IN = V , reset not asserted, T = -40°C to +85°C. Typical values are at T = +25°C,Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.Terminal Voltages (with respect to GND)V CC , BATT, OUT.......................................................-0.3V to +6V RESET (open drain), RESET (open drain)................-0.3V to +6V BATT ON, RESET (push-pull), RESET IN,WDI, CE IN, CE OUT...........................-0.3V to (V OUT + 0.3V)MR ..............................................................-0.3V to (V CC + 0.3V)Input CurrentV CC Peak ..............................................................................1A V CC Continuous.............................................................250mA BATT Peak.....................................................................250mA BATT Continuous.............................................................40mAGND...............................................................................75mA Output CurrentOUT...............................Short-Circuit Protected for up to 10s RESET, RESET , BATT ON, CE OUT...............................20mA Continuous Power Dissipation (T A = +70°C)8-Pin SOT23 (derate 8.75mW/°C above +70°C)........700mW Operating Temperature Range ...........................-40°C to +85°C Storage Temperature Range.............................-65°C to +150°C Junction Temperature .....................................................+150°C Lead Temperature (soldering, 10s).................................+300°CMAX6365–MAX6368SOT23, Low-Power µP Supervisory Circuits with Battery Backup and Chip-Enable Gating_______________________________________________________________________________________3ELECTRICAL CHARACTERISTICS (continued)(V CC = +2.4V to +5.5V, V BATT = +3.0V, CE IN = V CC , reset not asserted, T A = -40°C to +85°C. Typical values are at T A = +25°C,M A X 6365–M A X 6368SOT23, Low-Power µP Supervisory Circuits with Battery Backup and Chip-Enable Gating 4_______________________________________________________________________________________Typical Operating Characteristics(T A = +25°C, unless otherwise noted.)8109121115141316-400-2020406080SUPPLY CURRENTvs. TEMPERATURE (NO LOAD)TEMPERATURE (°C)S U P P L Y C U R R E N T (µA )0.20.60.40.81.01.2BATTERY SUPPLY CURRENT (BACKUP MODE) vs. TEMPERATURETEMPERATURE (°C)B A T T E R Y S U P P L YC U R R E N T (µA )-402040-200608021437658-40-2020406080BATT-TO-OUT ON-RESISTANCEvs. TEMPERATURETEMPERATURE (°C)B A T T -T O -O U T O N -R E S I S T A NC E (Ω)ELECTRICAL CHARACTERISTICS (continued)(V= +2.4V to +5.5V, V = +3.0V, CE IN = V , reset not asserted, T = -40°C to +85°C. Typical values are at T = +25°C,Note 2:V BATT can be 0 anytime, or V CC can go down to 0 if V BATT is active (except at startup).Note 3:RESET is pulled up to OUT. Specifications apply for OUT = V CC or OUT = BATT.Note 4:The chip-enable resistance is tested with V CC = V TH(MAX)and CE IN = V CC /2.MAX6365–MAX6368SOT23, Low-Power µP Supervisory Circuits with Battery Backup and Chip-Enable Gating_______________________________________________________________________________________5Typical Operating Characteristics (continued)(T A = +25°C, unless otherwise noted.)00.40.20.80.61.21.01.4-4020-20406080V CC TO OUT ON-RESISTANCEvs. TEMPERATURETEMPERATURE (°C)V C C T O O U T O N -R E S I S T A N C E (Ω)190195205200210RESET TIMEOUT PERIOD vs. TEMPERATUREM A X 6365/8-05TEMPERATURE (°C)R E S E T T I M E O U T P E R I O D (m s )-402040-206080301575604513512010590TEMPERATURE (°C)P R O P A G A T I O N D E L A Y (µs )-402040-206080V CC vs. TEMPERATURE2.03.02.55.04.54.03.5RESET THRESHOLD vs. TEMPERATURETEMPERATURE (°C)T H R E S H O L D (V )-402040-206080110010100010,000MAXIMUM TRANSIENT DURATION vs. RESET THRESHOLD OVERDRIVERESET THRESHOLD OVERDRIVE V TH - V CC (mV)M A X I M U M T R A N S I E N T D U R A T I O N (µs )40030035025020005015010003215498761000.5 1.0 1.5 2.0 2.5 3.0 3.5BATTERY SUPPLY CURRENT vs. SUPPLY VOLTAGEV CC (V)B A T T E R Y S U P P L YC U R R E N T (µA )M A X 6365–M A X 6368SOT23, Low-Power µP Supervisory Circuits with Battery Backup and Chip-Enable Gating 6_______________________________________________________________________________________1.2341.2351.236MAX6368RESET IN THRESHOLD vs. TEMPERATUREM A X 6365/8 -10TEMPERATURE (°C)V R T H (V )-402040-2060801.01.91.61.32.82.52.2MAX6368RESET IN TO RESET PROPAGATION DELAYvs. TEMPERATURETEMPERATURE (°C)P R O P A G A T I O N D E L A Y (µs )-402040-206080013245C LOAD (pF)P R O P A G A T I O N D E L A Y (n s )10050150200CHIP-ENABLE PROPAGATION DELAY vs. CE OUT LOAD CAPACITANCE515102025-40-2020406080TEMPERATURE (°C)C E I N T O C E O U T O N -R E S I S T A N C E (Ω)CE IN TO CE OUT ON-RESISTANCEvs. TEMPERATURE1.01.31.21.11.51.41.91.81.71.62.0-40-2020406080TEMPERATURE (°C)W A T C H D O G T I M E O U T P E R I O D (s )MAX6366WATCHDOG TIMEOUT PERIODvs. TEMPERATURETypical Operating Characteristics (continued)(T A = +25°C, unless otherwise noted.)MAX6365–MAX6368SOT23, Low-Power µP Supervisory Circuits with Battery Backup and Chip-Enable Gating_______________________________________________________________________________________7M A X 6365–M A X 6368SOT23, Low-Power µP Supervisory Circuits with Battery Backup and Chip-Enable Gating 8_______________________________________________________________________________________Detailed DescriptionThe Typical Operating Circuit shows a typical connec-tion for the MAX6365–MAX6368. OUT powers the static random-access memory (SRAM). If V CC is greater than the reset threshold (V TH ), or if V CC is lower than V TH but higher than V BATT , V CC is connected to OUT. If V CC is lower than V TH and V CC is less than V BATT ,BATT is connected to OUT. OUT supplies up to 150mA from V CC . In battery-backup mode, an internal MOSFET connects the backup battery to OUT. The on-resistance of the MOSFET is a function of backup-battery voltage and is shown in the BATT-to-OUT On-Resistance vs.Temperature graph in the T ypical Operating Char-acteristics .Chip-Enable Signal GatingThe MAX6365–MAX6368 provide internal gating of CE signals to prevent erroneous data from being written toCMOS RAM in the event of a power failure. During nor-mal operation, the CE gate is enabled and passes all CE transitions. When reset asserts, this path becomes disabled, preventing erroneous data from corrupting the CMOS RAM. All of these devices use a series trans-mission gate from CE IN to CE OUT. The 2ns propaga-tion delay from CE IN to CE OUT allows the devices to be used with most µPs and high-speed DSPs.During normal operation, CE IN is connected to CE OUT through a low on-resistance transmission gate.This is valid when reset is not asserted. If CE IN is high when reset is asserted, CE OUT remains high regard-less of any subsequent transitions on CE IN during the reset event.If CE IN is low when reset is asserted, CE OUT is held low for 12µs to allow completion of the read/write oper-ation (F igure 1). After the 12µs delay expires, the CEFunctional DiagramMAX6365–MAX6368SOT23, Low-Power µP Supervisory Circuits with Battery Backup and Chip-Enable Gating_______________________________________________________________________________________9OUT goes high and stays high regardless of any sub-sequent transitions on CE IN during the reset event.When CE OUT is disconnected from CE IN, CE OUT is actively pulled up to OUT.The propagation delay through the chip-enable circuit-ry depends on both the source impedance of the drive to CE IN and the capacitive loading at CE OUT. The chip-enable propagation delay is production tested from the 50% point of CE IN to the 50% point of CE OUT, using a 50Ωdriver and 50pF load capacitance.Minimize the capacitive load at CE OUT to minimize propagation delay, and use a low-output-impedance driver.Backup-Battery SwitchoverIn a brownout or power failure, it may be necessary to preserve the contents of the RAM. With a backup bat-tery installed at BATT, the MAX6365–MAX6368 auto-matically switch the RAM to backup power when V CC falls. The MAX6367 has a BATT ON output that goes high in battery-backup mode. These devices require two conditions before switching to battery-backup mode:1) V CC must be below the reset threshold.2) V CC must be below V BATT .Table 1 lists the status of the inputs and outputs in bat-tery-backup mode. The devices do not power up if theonly voltage source is on BATT. OUT only powers up from V CC at startup.Many µP-based products require manual reset capabili-ty, allowing the user or external logic circuitry to initiate a reset. For the MAX6365, a logic low on MR asserts reset.Reset remains asserted while MR is low and for a mini-mum of 150ms (t RP ) after it returns high. MR has an inter-nal 20k Ωpullup resistor to V CC . This input can be driven with TTL/CMOS logic levels or with open-drain/collector outputs. Connect a normally open momentary switch from MR to GND to create a manual reset function; exter-nal debounce circuitry is not required. If MR is driven from long cables or the device is used in a noisy environ-ment, connect a 0.1µF capacitor from MR to GND to pro-vide additional noise immunity.Figure 1. Reset and Chip-Enable TimingM A X 6365–M A X 6368SOT23, Low-Power µP Supervisory Circuits with Battery Backup and Chip-Enable Gating 10______________________________________________________________________________________Watchdog Input (MAX6366 Only)The watchdog monitors µP activity through the watch-dog input (WDI). If the µP becomes inactive, reset asserts. To use the watchdog function, connect WDI to a bus line or µP I/O line. A change of state (high to low,low to high, or a minimum 100ns pulse) resets the watchdog timer. If WDI remains high or low for longer than the watchdog timeout period (t WD ), the internal watchdog timer runs out and a reset pulse is triggered for the reset timeout period (t RP ). The internal watchdog timer clears whenever reset asserts or whenever WDI sees a rising or falling edge. If WDI remains in either a high or low state, a reset pulse asserts periodically after every t WD (F igure 2). Leave WDI unconnected to dis-able the watchdog function.BATT ON Indicator (MAX6367 Only)BATT ON is a push-pull output that drives high when in battery-backup mode. BATT ON typically sinks 3.2mA at 0.1V saturation voltage. In battery-backup mode, this terminal sources approximately 10µA from OUT. Use BATT ON to indicate battery-switchover status or to supply base drive to an external pass transistor for higher current applications (Figure 3).RESET IN Comparator (MAX6368 Only)RESET IN is compared to an internal 1.235V reference.If the voltage at RESET IN is less than 1.235V, reset asserts. Use the RESET IN comparator as an undervolt-age detector to signal a failing power supply or as a secondary power-supply reset monitor.To program the reset threshold (V RTH ) of the secondary power supply, use the following (see Typical Operating Circuit ):V RTH = V REF (R1 / R2 + 1)where V REF = 1.235V. To simplify the resistor selection,choose a value for R2 and calculate R1:R1 = R2 [(V RTH / V REF ) - 1]Since the input current at RESET IN is 25nA (max),large values (up to 1M Ω) can be used for R2 with no significant loss in accuracy. For example, in the Typical Operating Circuit , the MAX6368 monitors two supply voltages. To monitor the secondary 5V logic or analog supply with a 4.60V nominal programmed reset thresh-old, choose R2 = 100k Ω, and calculate R1 = 273k Ω.Reset OutputA µP ’s reset input starts the µP in a known state. The MAX6365–MAX6368 µP supervisory circuits assert a reset to prevent code-execution errors during power-up, power-down, and brownout conditions. RESET is guaranteed to be a logic low or logic high, depending on the device chosen (see Ordering Information ).RESET or RESET asserts when V CC is below the reset threshold and for at least 150ms (t RP ) after V CC rises above the reset threshold. RESET or RESET also asserts when MR is low (MAX6365) and when RESET IN is less than 1.235V (MAX6368). The MAX6366 watch-dog function will cause RESET (or RESET ) to assert in pulses following a watchdog timeout (Figure 2).Applications InformationOperation Withouta Backup Power SourceThe MAX6365–MAX6368 provide battery-backup func-tions. If a backup power source is not used, connect BATT to GND and OUT to V CC .Watchdog Software ConsiderationsOne way to help the watchdog timer monitor the soft-ware execution more closely is to set and reset the watchdog at different points in the program rather than pulsing the watchdog input periodically. F igure 4shows a flow diagram in which the I/O driving theFigure 2. MAX6366 Watchdog Timeout Period and Reset Active TimeMAX6365–MAX6368SOT23, Low-Power µP Supervisory Circuits with Battery Backup and Chip-Enable Gating______________________________________________________________________________________11watchdog is set low in the beginning of the program,set high at the beginning of every subroutine or loop,and set low again when the program returns to the beginning. If the program should hang in any subrou-tine, the problem would be quickly corrected.Replacing the Backup BatteryWhen V CC is above V TH , the backup power source can be removed without danger of triggering a reset pulse.The device does not enter battery-backup mode when V CC stays above the reset threshold voltage.Negative-Going V CC TransientsThese supervisors are relatively immune to short-dura-tion, negative-going V CC transients. Resetting the µP when V CC experiences only small glitches is usually not desirable.The T ypical Operating Characteristics section has a Maximum Transient Duration vs. Reset Threshold Overdrive graph for which reset is not asserted. The graph was produced using negative-going V CC pulses,starting at V CC and ending below the reset threshold by the magnitude indicated (reset threshold overdrive).The graph shows the maximum pulse width that a neg-ative-going V CC transient can typically have without triggering a reset pulse. As the amplitude of the tran-sient increases (i.e., goes further below the reset threshold), the maximum allowable pulse width decreases. Typically, a V CC transient that goes 100mV below the reset threshold and lasts for 30µs will not trig-ger a reset pulse.A 0.1µF bypass capacitor mounted close to the V CC pin provides additional transient immunity.M A X 6365–M A X 6368SOT23, Low-Power µP Supervisory Circuits with Battery Backup and Chip-Enable Gating 12______________________________________________________________________________________standard versions only. Contact factory for availability of nonstandard versions.MAX6365–MAX6368SOT23, Low-Power µP Supervisory Circuits with Battery Backup and Chip-Enable Gating______________________________________________________________________________________13Pin Configurations (continued)M A X 6365–M A X 6368SOT23, Low-Power µP Supervisory Circuits with Battery Backup and Chip-Enable Gating 14______________________________________________________________________________________Typical Operating CircuitChip InformationTRANSISTOR COUNT: 729PROCESS: CMOSSOT23, Low-Power µP Supervisory Circuitswith Battery Backup and Chip-Enable GatingMAX6365–MAX6368Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________15©2001 Maxim Integrated Products Printed USAis a registered trademark of Maxim Integrated Products.Package Information。
MAX6306UK30D1+中文资料
General DescriptionThe MAX6305–MAX6313 CMOS microprocessor (µP)supervisory circuits are designed to monitor more than one power supply. Ideal for monitoring both 5V and 3.3V in personal computer systems, these devices assert a system reset if any of the monitored supplies falls outside the programmed threshold. Low supply current (15µA) and a small package suit them for portable applications. The MAX6305–MAX6313 are specifically designed to ignore fast transients on any monitored supply.These devices are available in a SOT23-5 package,have factory-programmed reset thresholds from 2.5V to 5.0V (in 100mV increments), and feature four power-on reset timeout periods. Ten standard versions are avail-able. Contact the factory for availability of non standard versions.ApplicationsPortable Computers Computers ControllersIntelligent InstrumentsPortable/Battery-Powered Equipment Multivoltage Systems: 3V/5V, 5V/12V, 5V/24V Embedded Control SystemsFeatureso Small 5-Pin SOT23 Packageo Precision Factory-Set V CC Reset Thresholds;Available in 0.1V Increments from 2.5V to 5V o Immune to Short V CC Transientso Guaranteed RESET Valid to V CC = 1V o Guaranteed Over Temperature o 8µA Supply Currento Factory-Set Reset Timeout Delay from 1ms (min) to 1120ms (min)o No External Components o Manual Reset Inputo Under/Overvoltage Supply MonitoringMAX6305–MAX63135-Pin, Multiple-Input,Programmable Reset ICs________________________________________________________________Maxim Integrated Products119-1145; Rev 5; 4/08†The MAX6306/MAX6307/MAX6309/MAX6310/MAX6312/MAX6313 are available with factory-set V CC reset thresholds from 2.5V to 5V, in 0.1V increments. Insert the desired nominal reset threshold (from Table 1) into the blanks following the letters UK.All parts also offer factory-programmed reset timeout periods.Insert the number corresponding to the desired nominal timeout period index following the “D” in the part number (D1 = 1ms min,D2 = 20ms min, D3 = 140ms min, and D4 = 1120ms min). There are 10 standard versions with a required order increment of 2,500pieces. Sample stock is generally held on the standard versions only (see Standard Versions table). Required order increment is 10,000 pieces for non-standard versions. Contact factory for availability of non-standard versions. All devices available in tape-and-reel only.Devices are available in both leaded and lead-free packaging.Specify lead-free by replacing “-T” with “+T” when ordering.Pin Configurations and Typical Operating Circuit appear atend of data sheet.Ordering Information continued at end of data sheet.Standard Versions Table appears at end of data sheet._______________________________________________________________Selector TableFor pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,or visit Maxim’s website at .M A X 6305–M A X 63135-Pin, Multiple-Input, Programmable Reset ICsABSOLUTE MAXIMUM RATINGSELECTRICAL CHARACTERISTICSV CC = +2.5V to +5.5V for the MAX6305/MAX6308/MAX6311, V CC = (V TH + 2.5%) to +5.5V for the MAX6306/MAX6307/MAX6309/Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.V CC ...........................................................................-0.3V to +6V All Other Pins..............................................-0.3V to (V CC + 0.3V)Input/Output Current, All Pins.............................................20mA Rate of Rise, V CC ............................................................100V/µs Continuous Power Dissipation (T A = +70°C)SOT23-5 (derate 7.1mW/°C above +70°C).................571mWOperating Temperature RangeMAX63_ _UK _ _D_-T.........................................0°C to +70°C MAX63_ _EUK _ _D_-T...................................-40°C to +85°C Storage Temperature Range.............................-65°C to +160°C Lead Temperature (soldering, 10sec).............................+300°CMAX6305–MAX63135-Pin, Multiple-Input, Programmable Reset ICs_______________________________________________________________________________________3ELECTRICAL CHARACTERISTICS (continued)V CC = +2.5V to +5.5V for the MAX6305/MAX6308/MAX6311, V CC = (V TH + 2.5%) to +5.5V for the MAX6306/MAX6307/MAX6309/Note 2: The MAX6305/MAX6308/MAX6311 switch from undervoltage reset to normal operation between 1.5V < V CC < 2.5V.Note 3: The MAX6306/MAX6307/MAX6309/MAX6310/MAX6312/MAX6313 monitor V CC through an internal factory-trimmed voltagedivider, which programs the nominal reset threshold. Factory-trimmed reset thresholds are available in approximately 100mV increments from 2.5V to 5V (Table 1).Note 4:Guaranteed by design.M A X 6305–M A X 63135-Pin, Multiple-Input, Programmable Reset ICs 4_________________________________________________________________________________________________________________________________Typical Operating Characteristics(V CC = +5V, T A = +25°C, unless otherwise noted.)5.05.56.06.57.07.58.08.59.09.5-60-40-2020406080100SUPPLY CURRENT vs. TEMPERATURETEMPERATURE (°C)S U P P L Y C U R R E N T (μA )01020304050607080-60-40-2020406080100V CC FALLING PROPAGATION DELAYvs. TEMPERATURETEMPERATURE (°C)P R O P A G A T I O N D E L A Y (n s )010203040506070-60-40-20020406080100OVRST IN RISING PROPAGATION DELAY vs. TEMPERATURE (OVERVOLTAGE RESET INPUT)TEMPERATURE (°C)P R O P A G A T I O N D E L A Y (n s )020406080100120-60-40-2020406080100RST IN_ FALLING PROPAGATION DELAY vs. TEMPERATURETEMPERATURE (°C)R S T I N _ P R O P A G A T I O N D E L A Y (n s )104001200800MAXIMUM TRANSIENT DURATION vs.VCC RESET THRESHOLD OVERDRIVE10OVERDRIVE, V TH - V CC (mV)T R A N S I E N T D U R A T I O N (μs )100100010,0000.900.920.940.960.981.001.021.041.061.081.10-60-40-20020406080100RESET TIMEOUT vs. TEMPERATURE6305 T O C 05TEMPERATURE (°C)N O R M A L I Z E D R E S E T T I M E O U T0.9900.9920.9940.9960.9981.0001.0021.0041.0061.0081.010-60-40-2020406080100RESET THRESHOLD vs. TEMPERATURE6305 T O C 06TEMPERATURE (°C)N O R M A L I Z E D R E S E T T H R E S H O L D (V /V )104001200800MAXIMUM TRANSIENT DURATION vs.OVRST IN THRESHOLD OVERDRIVE10OVERDRIVE, V OVRST IN - V REF (mV)T R A N S I E N T D U R A T I O N (μs )100100010,000104001200800MAXIMUM TRANSIENT DURATION vs.RST IN_ THRESHOLD OVERDRIVE10OVERDRIVE, V REF - V RST IN (mV)T R A N S I E N T D U R A T I O N (μs )100100010,000_______________Detailed DescriptionThe MAX6305–MAX6313 CMOS microprocessor (µP)supervisory circuits are designed to monitor more than one power supply and issue a system reset when any monitored supply falls out of regulation. The MAX6305/MAX6308/MAX6311 have two adjustable undervoltage reset inputs (RST IN1 and RST IN2). The MAX6306/MAX6307/MAX6309/MAX6310/MAX6312/MAX6313 mon-itor V CC through an internal, factory-trimmed voltage divider. The MAX6306/MAX6309/MAX6312 have, in addition, an adjustable undervoltage reset input and a manual-reset input. The internal voltage divider sets the reset threshold as specified in the device part number (Table 1). The MAX6307/MAX6310/ MAX6313 feature an adjustable undervoltage reset input (RST IN) and an adjustable overvoltage reset input (OVRST IN) in addition to the factory-trimmed reset threshold on the V CC moni-tor. Program the adjustable reset inputs with an external resistor divider (see Adjustable Reset Inputs section).Reset OutputsA µP’s reset input starts the µP in a known state. These µP supervisory circuits assert reset to prevent code-execution errors during power-up, power-down, or brownout conditions.RESET (MAX6305–MAX6310) and RESET (MAX6311/MAX6312/MAX6313) are guaranteed to be asserted at a valid logic level for V CC > 1V (see Electrical Characteristics ). Once all monitored voltages exceed their programmed reset thresholds, an internal timer keeps reset asserted for the reset timeout period (t RP );after this interval, reset deasserts.If a brownout condition occurs (any or all monitored volt-ages dip outside their programmed reset threshold),reset asserts (RESET goes high; RESET goes low). Any time any of the monitored voltages dip below their reset threshold, the internal timer resets to zero and reset asserts. The internal timer starts when all of the moni-tored voltages return above their reset thresholds, and reset remains asserted for a reset timeout period. The MAX6305/MAX6306/MAX6307 feature an active-low,MAX6305–MAX63135-Pin, Multiple-Input, Programmable Reset ICs_______________________________________________________________________________________5______________________________________________________________Pin DescriptionM A X 6305–M A X 6313open-drain, N-channel output. The MAX6308/MAX6309/MAX6310 feature an active-low, complementary output structure that both sinks and sources current, and the MAX6311/MAX6312/MAX6313 have an active-high com-plementary reset output.The MAX6305/MAX6308/MAX6311 switch from under-voltage lockout operation to normal operation between 1.5V < V CC < 2.5V. Below 1.5V, V CC undervoltage-lockout mode asserts RESET . Above 2.5V, V CC normal-operation mode asserts reset if RST IN_ falls below the RST IN_ threshold.Manual-Reset Input(MAX6306/MAX6309/MAX6312)Many µP-based products require manual-reset capability,allowing an operator or external logic circuitry to initiate a reset. A logic low on MR asserts reset. Reset remains asserted while MR is low, and for a reset active timeout period (t RP ) after MR returns high. This input has an inter-nal 63.5k Ωpull-up resistor, so it can be left open if it is not used. MR can be driven with TTL-logic levels in 5V sys-tems, with CMOS-logic levels in 3V systems, or with open-drain/collector output devices. Connect a normally open momentary switch from MR to GND to create a manual-reset function; external debounce circuitry is not required.If MR is driven from long cables or if the device is used in a noisy environment, connecting a 0.1µF capacitor from MR to ground provides additional noise immunity.The MR pin has internal ESD-protection circuitry that may be forward biased under certain conditions, drawing excessive current. For example, assume the circuitry driv-ing MR uses a +5V supply other than V CC . If V CC drops or browns out lower than +4.7V, MR ’s absolute maximum rat-ing is violated (-0.3V to (V CC + 0.3V)), and undesirable current flows through the ESD structure from MR to V CC .To avoid this, it is recommended that the supply for the MR pin be the same as the supply monitored by V CC . In this way, the voltage at MR will not exceed V CC .Adjustable Reset InputsThe MAX6305–MAX6313 each have one or more reset inputs (RST IN_ /OVRST IN). These inputs are com-pared to the internal reference voltage (F igure 1).Connect a resistor voltage divider to RST IN_ such that V RST IN_falls below V RSTH (1.23V) when the monitored voltage (V IN ) falls below the desired reset threshold (V TH ) (F igure 2). Calculate the desired reset voltage with the following formula:R1 + R2V TH = ________x VRSTHR25-Pin, Multiple-Input, Programmable Reset ICs 6_______________________________________________________________________________________Figure 1. Functional DiagramMAX6305–MAX63135-Pin, Multiple-Input, Programmable Reset ICs_______________________________________________________________________________________7The ±25nA max input leakage current allows resistors on the order of megohms. Choose the pull-up resistor in the divider to minimize the error due to the input leakage cur-rent. The error term in the calculated threshold is simply:±25nA x R1If you choose R1 to be 1M Ω, the resulting error is ±25 x 10-9x 1 x 106= ±25mV.Like the V CC voltage monitors on the MAX6306/MAX6307/MAX6309/MAX6310/MAX6312/MAX6313, the RST IN_inputs (when used with a voltage divider) are designed to ignore fast voltage transients. Increase the noise immunity by connecting a capacitor on the order of 0.1µF between RST IN and GND (Figure 2). This creates a single-pole lowpass filter with a corner frequency given by:f = (1/2π) / (R1 + R2)(R1 x R2 x C)For example, if R1 = 1M Ωand R2 = 1.6M Ω, adding a 0.1µF capacitor from RST IN_ to ground results in a lowpass corner frequency of f = 2.59Hz. Note that adding capacitance to RST IN slows the circuit’s overall response time.__________Applications InformationInterfacing to µPs with Bidirectional Reset PinsSince the RESET output on the MAX6305/MAX6306/MAX6307 is open drain, these devices interface easily with µPs that have bidirectional reset pins, such as the Motorola 68HC11. Connecting the µP supervisor’s RESET output directly to the microcontroller’s RESET pin with a single pull-up resistor allows either device to assert reset (Figure 3).Negative-Going V CC TransientsIn addition to issuing a reset to the µP during power-up,power-down, and brownout conditions, these devices are relatively immune to short-duration, negative-going V CC transients (glitches).The Typical Operating Characteristics show the Maximum Transient Duration vs. V CC Reset Threshold Overdrive, for which reset pulses are not generated.The graph was produced using negative-going pulses,starting at V TH max, and ending below the pro-grammed reset threshold by the magnitude indicated (reset threshold overdrive). The graph shows the maxi-mum pulse width that a negative-going V CC transient may typically have without causing a reset pulse to be issued. As the amplitude of the transient increases (i.e.,goes farther below the reset threshold), the maximum allowable pulse width decreases.RST IN_/OVRST IN are also immune to negative/positive-going transients (see Typical Operating Characteristics ).A 0.1µF bypass capacitor mounted close to the RST IN_,OVRST IN, and/or the V CC pin provides additional tran-sient immunity.Ensuring a Valid RESET /RESETOutput Down to V CC = 0VWhen V CC falls below 1V, push/pull structured RESET /RESET current sinking (or sourcing) capabilities decrease drastically. High-impedance CMOS-logic inputs connected to RESET can drift to undetermined voltages. This presents no problem in most applica-tions, since most µPs and other circuitry do not operate with V CC below 1V. In those applications where RESET must be valid down to 0V, adding a pull-down resistor between RESET and ground sinks any stray leakageFigure 2. Increasing Noise ImmunityFigure 3. Interfacing to µPs with Bidirectional Reset I/Ocurrents, holding RESET low (Figure 4). The pull-down resistor’s value is not critical; 100k Ωis large enough not to load RESET and small enough to pull RESET to ground. For applications where RESET must be valid to V CC , a 100k Ωpull-up resistor between RESET and V CC will hold RESET high when V CC falls below 1V (Figure 5).Since the MAX6305/MAX6306/MAX6307 have open-drain, active-low outputs, they typically use a pull-up resistor. With these devices and under these conditions (V CC < 1V), RESET will most likely not maintain an active condition, but will drift toward a nonactive level due to the pull-up resistor and the RESET output’s reduction in sinking capability. These devices are not recommended for applications that require a valid RESET output below 1V.* Factory-trimmed reset thresholds are available in approximately 100mV increments with a ±1.5% room-temperature variance.M A X 6305–M A X 63135-Pin, Multiple-Input, Programmable Reset ICs 8_______________________________________________________________________________________Figure 4. Ensuring RESET Valid to V CC = 0VFigure 5. Ensuring RESET Valid to V CC = 0VTable 1. Factory-Trimmed Reset Thresholds*MAX6305–MAX63135-Pin, Multiple-Input, Programmable Reset ICs_______________________________________________________________________________________9Chip InformationTRANSISTOR COUNT: 800Typical Operating Circuit†The MAX6306/MAX6307/MAX6309/MAX6310/MAX6312/MAX6313 are available with factory-set V CC reset thresholds from 2.5V to 5V, in 0.1V increments. Insert the desired nominal reset threshold (from Table 1) into the blanks following the letters UK.All parts also offer factory-programmed reset timeout periods.Insert the number corresponding to the desired nominal timeout period index following the “D” in the part number (D1 = 1ms min,D2 = 20ms min, D3 = 140ms min, and D4 = 1120ms min). There are 10 standard versions with a required order increment of 2,500pieces. Sample stock is generally held on the standard versions only (see Standard Versions table). Required order increment is 10,000 pieces for non-standard versions. Contact factory for avail-ability of non-standard versions. All devices available in tape-and-reel only.Devices are available in both leaded and lead-free packaging.Specify lead-free by replacing “-T” with “+T” when ordering.M A X 6305–M A X 63135-Pin, Multiple-Input, Programmable Reset ICs 10______________________________________________________________________________________Pin ConfigurationsPackage InformationFor the latest package outline information, go to /packages .Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________11©2008 Maxim Integrated Productsis a registered trademark of Maxim Integrated Products, Inc.MAX6305–MAX6313 5-Pin, Multiple-Input, Programmable Reset ICs元器件交易网。
MAX4080SAUA+中文资料
Precision High-Voltage Current Sources
Features
♦ Wide 4.5V to 76V Input Common-Mode Range ♦ Bidirectional or Unidirectional ISENSE ♦ Low-Cost, Compact, Current-Sense Solution ♦ Three Gain Versions Available
TEMP RANGE -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C
The MAX4080/MAX4081 operate from a 4.5V to 76V single supply and draw only 75µA of supply current. These devices are specified over the automotive operating temperature range (-40°C to +125°C) and are available in a space-saving 8-pin µMAX or SO package.
For maximum versatility, the 76V input voltage range applies independently to both supply voltage (VCC) and common-mode input voltage (VRS+). High-side current monitoring does not interfere with the ground path of the load being measured, making the MAX4080/MAX4081 particularly useful in a wide range of high-voltage systems.
MAX8887EZK18中文资料
General DescriptionThe MAX8887/MAX8888 low-dropout linear regulators operate from a +2.5V to +5.5V input and deliver up to 300mA continuous (500mA pulsed) current. The MAX8887 is optimized for low-noise operation, while the MAX8888 includes an open-drain POK ouput flag. Both regulators feature exceptionally low 100mV dropout at 200mA. These devices are available in a variety of pre-set output voltages in the +1.5V to +3.3V range.An internal PMOS pass transistor allows the low 55µA supply current to remain independent of load, making these devices ideal for portable battery-powered equip-ment such as personal digital assistants (PDAs), cellu-lar phones, cordless phones, and notebook computers.Other features include a micropower shutdown mode,short-circuit protection, thermal shutdown protection,and an active-low open-drain power-OK (POK) output that indicates when the output is out of regulation. The MAX8887/MAX8888 are available in a thin 5-pin SOT23package that is only 1mm high.________________________ApplicationsNotebook Computers Wireless HandsetsPDAs and Palmtop Computers Digital Cameras PCMCIA Cards Hand-Held InstrumentsFeatureso Guaranteed 300mA Ouput Current (500mA for pulsed loads)o Low 100mV Dropout at 200mA Load o POK Output (MAX8888)o 42µV RMS Ouput Noise (MAX8887)o Preset Output Voltages (1.5V, 1.8V, 2.85V, and 3.3V)o 55µA No-Load Supply Currento Thermal-Overload and Short–Circuit Protection o Foldback Ouput Current-Limit Protection o 60dB PSRR at 1kHz o 0.1µA Shutdown Currento Thin 5-Pin SOT23 Package, 1mm HighMAX8887/MAX8888Low-Dropout, 300mA Linear Regulators in SOT23________________________________________________________________Maxim Integrated Products 1Pin ConfigurationsTypical Operating Circuit19-1859; Rev 0; 12/00For price, delivery, and to place orders,please contact Maxim Distribution at 1-888-629-4642,or visit Maxim’s website at .Ordering Information*Other versions (xy) between +1.5 and +3.3V are available in 100mV increments. Contact factory for other versions. Minimum order quantity is 25,000 units.M A X 8887/M A X 8888Low-Dropout, 300mA Linear Regulators in SOT232_______________________________________________________________________________________ABSOLUTE MAXIMUM RATINGSELECTRICAL CHARACTERISTICS(V IN = V OUT + 1V, SHDN = IN, T A = -40°C to +85°C, unless otherwise noted.) (Note 1)Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.IN, SHDN , POK, to GND........................................-0.3V to +6.0V OUT, BP to GND............................................-0.3 to (V IN + 0.3V)Output Short-Circuit Duration.....................................Continuous Continuous Power Dissipation (T A = +70°C)5-Pin SOT23 (derate 9.1mW/°C above +70°C)............727mWOperating Temperature Ranges..........................-40°C to +85°C Junction Temperature......................................................+150°C Storage Temperature Range.............................-65°C to +150°C Lead Temperature (soldering, 10s).................................+500°CMAX8887/MAX8888Low-Dropout, 300mA Linear Regulators in SOT23_______________________________________________________________________________________3ELECTRICAL CHARACTERISTICS (continued)(V IN = V OUT + 1V, SHDN = IN, T A = -40°C to +85°C, unless otherwise noted.) (Note 1)Note 2:Typical and maximum dropout voltage for different output voltages are shown in Typical Operating Characteristics curve.Typical Operating Characteristics(Typical Operating Circuit , T A = +25°C, unless otherwise noted.)01.00.52.01.53.02.53.52.03.03.52.54.04.55.05.5OUTPUT VOLTAGE vs. INPUT VOLTAGEINPUT VOLTAGE (V)O U T P U T V O L T A G E (V )-1.0-0.6-0.80.0-0.2-0.40.20.40.80.61.010050150200250300OUTPUT VOLTAGE ACCURACYvs. LOAD CURRENTM A X 8887-8 t o c 02LOAD CURRENT (mA)% D E V I A T I O N (%)0-0.05-0.02-0.03-0.04-0.010.00.010.020.030.040.05-4010-15356085OUTPUT VOLTAGE ACCURACYvs. TEMPERATURETEMPERATURE (°C)% D E V I A T I O NM A X 8887/M A X 8888Low-Dropout, 300mA Linear Regulators in SOT234_______________________________________________________________________________________020406080100120140160010050150200250300DROPOUT VOLTAGE vs. LOAD CURRENTLOAD CURRENT (mA)V D R O P O U T (m V )501001502002503002.5 2.7 2.93.1 3.3DROPOUT VOLTAGE vs. OUTPUT VOLTAGEV OUT (V)V D R O P O U T (m V )1.02.03.04.05.0INPUT VOLTAGE (V)0502510075125150GROUND-PIN CURRENT vs. INPUT VOLTAGEG R O U N D -P I N C U R R E N T (µA )02060408010010050150200250300GROUND-PIN CURRENT vs. LOAD CURRENTLOAD CURRENT (mA)G R O U N D -P I N C U R R E N T (µA )5056545258606264666870-4010-15356085GROUND-PIN CURRENT vs. TEMPERATURETEMPERATURE (°C)G R O U N D -P I N C U R R E N T (µA )700.010.111010010006050403020POWER-SUPPLY REJECTION RATIOvs. FREQUENCYFREQUENCY (kHz)P S R R (d B)10MAX8887OUTPUT NOISE DC TO 1MHzV OUT 50µV/divTIME (40ms/div)LOAD-TRANSIENT RESPONSE50mV/div AC-COUPLED 300mA10mAV OUTI OUTTIME (10µs/div)Typical Operating Characteristics (continued)(Typical Operating Circuit , T A = +25°C, unless otherwise noted.)MAX8887/MAX8888Low-Dropout, 300mA Linear Regulators in SOT23LINE-TRANSIENT RESPONSE20mV/div AC-COUPLED+4V+4.5VV OUTV INV OUT = +3.3V I LOAD = 100mATIME (100µs/div)SHUTDOWN WAVEFORMV SHDN1V/divDC-COUPLED2V/divV OUTTIME (20µs/div)POK WAVEFORMMAX8887-9 toc152V/div2V/div2V/divV OUT V POK V INV OUT = +3.3V, R LOAD = 100ΩTIME (20ms/div)Pin DescriptionFUNCTIONRegulator Input. Supply voltage can range from 2.5V to 5.5V. Bypass with 2.2Capacitor Selection and Regulator Stability ).Active-Low Shutdown Input. A logic low reduces the supply current to below 0.1In shutdown, POK and OUT are driven low. Connect to IN for normal operation.Open-Drain Active-Low POK Output. POK remains low while the output voltage (V below the reset threshold. Connect a 100k Ω pullup resistor to OUT to obtain a logic level output. POK is driven low in shutdown. If not used, leave this pin unconnected.Reference Bypass. Bypass with a low-leakage 0.01µF ceramic capacitor.LOAD-TRANSIENT RESPONSENEAR DROPOUT50mV/div AC-COUPLED300mA10mAV OUTI OUTTIME (10µs/div)Typical Operating Characteristics (continued)(Typical Operating Circuit , T A = +25°C, unless otherwise noted.)Detailed DescriptionThe MAX8887/MAX8888 are low-dropout, low-quies-cent-current linear regulators designed primarily for battery-powered applications. The devices supply loads up to 300mA and are available in several fixed output voltages in the +1.5 to +3.3V range. The MAX8887 is optimized for low-noise operation, while the MAX8888 includes an open-drain POK output flag.As illustrated in F igure 1, the MAX8888 consists of a 1.25V reference, error amplifier, P-channel pass tran-sistor, and internal feedback voltage divider.Internal P-Channel Pass TransistorThe MAX8887/MAX8888 feature a 0.5ΩP-channel MOSF ET pass transistor. Unlike similar designs using PNP pass transistors, P-channel MOSF ETs require no base drive, which reduces quiescent current. PNP-based regulators also waste considerable current in dropout when the pass transistor saturates and use high base drive currents under large loads. The MAX8887/MAX8888 do not suffer from these problems and consume only 55µA of quiescent current under heavy loads as well as in dropout.Ouput Voltage SelectionThe MAX8887/MAX8888 are supplied with various fac-tory-set output voltages ranging from 1.5V to 3.3V. The part number ’s two-digit suffix identifies the nominal out-put voltage. F or example, the MAX8887EUK33 has a preset output voltage of 3.3V (see Ordering Infor-mation ).ShutdownDrive SHDN low to enter shutdown. During shutdown,the output is disconnected from the input and supply current drops to 0.1µA. When in shutdown, POK and OUT are driven low. SHDN can be pulled as high as 6V, regardless of the input and output voltages.Power-OK OutputThe power-OK output (POK) pulls low when OUT is less than 93% of the nominal regulation voltage. Once OUT exceeds 93% of the nominal voltage, POK goes high impedance. POK is an open-drain N-channel output.To obtain a logic level output, connect a pullup resistor from POK to OUT. A 100k Ωresistor works well for most applications. POK can be used as a power-on-reset (POR) signal to a microcontroller (µC) or to drive other logic. Adding a capacitor from POK to ground creates POK delay. When the MAX8887 is shut down, POK is held low independent of the output voltage. If unused,leave POK grounded or unconnected.Current LimitThe MAX8887/MAX8888 monitor and control the pass transistor ’s gate voltage, limiting the output current to0.8A (typ). This current limit is reduced to 500mA (typ)when the output voltage is below 93% of the nominal value to provide foldback current limiting.Thermal-Overload ProtectionThermal-overload protection limits total power dissipa-tion in the MAX8887/MAX8888. When the junction tem-perature exceeds T J =+170°C, a thermal sensor turns off the pass transistor, allowing the device to cool. The thermal sensor turns the pass transistor on again after the junction temperature cools by 20°C, resulting in a pulsed output during continuous thermal overload con-ditions. Thermal overload protection protects the MAX8887/MAX8888 in the event of fault conditions. For continuous operation, do not exceed the absolute maxi-mum junction-temperature rating of T J =+150°C.Operating Region and Power DissipationThe MAX8887/MAX8888’s maximum power dissipation depends on the thermal resistance of the IC package and circuit board. The temperature difference between the die junction and ambient air, and the rate of air flow.The power dissipated in the device is P = I OUT ✕(V IN -V OUT ). The maximum allowed power dissipation is 727mW or:P MAX = (T J(MAX)- T A ) / (θJC + θCA )where T J(MAX)-T A is the temperature difference between the MAX8887/MAX8888 die junction and the surrounding air; θJC is the thermal resistance from the junction to the case; and θCA is the thermal resistance from the case through PC board, copper traces, and other materials to the surrounding air.Refer to Figure 2 for the MAX8887/MAX888 valid oper-ating region.Noise ReductionF or the MAX8887 only, an external 0.01µF bypass capacitor at BP creates a lowpass filter for noise reduc-tion. The MAX8887 exhibits 42µV RMS of output voltage noise with C BP = 0.01µF and C OUT = 2.2µF (see Typical Operating Characteristics ).Applications InformationCapacitor Selection and RegulatorStabilityConnect a 2.2µF ceramic capacitor between IN and ground and a 2.2µF ceramic capacitor between OUT and ground. The input capacitor (C IN ) lowers the source impedance of the input supply. Reduce noise and improve load-transient response, stability, and power-supply rejection by using a larger ceramic out-put capacitor such as 4.7µF.The output capacitor ’s (C OUT ) equivalent series resis-tance (ESR) affects stability and output noise. Use out-M A X 8887/M A X 8888Low-Dropout, 300mA Linear Regulators in SOT236_______________________________________________________________________________________put capacitors with an ESR of 0.1Ωor less to ensure sta-bility and optimum transient response. Surface-mount ceramic capacitors have very low ESR and are com-monly available in values up to 10µF. Connect C IN and C OUT as close to the MAX8887/MAX8888 as possible to minimize the impact of PC board trace inductance.Noise, PSRR, and Transient ResponseThe MAX8887/MAX8888 are designed to operate with low dropout voltages and low quiescent currents in bat-tery-powered systems while still maintaining excellent noise, transient response, and AC rejection. See the Typica l Opera ting Cha ra cteristics for a plot of power-supply rejection ratio (PSRR) versus frequency. When operating from noisy sources, improved supply-noise rejection and transient response can be achieved by increasing the values of the input and output bypass capacitors and through passive filtering techniques.Input-Output (Dropout) VoltageA regulator ’s minimum input-to-output voltage differen-tial (dropout voltage) determines the lowest usable sup-ply voltage at which the output is regulated. In battery-powered systems, this determines the useful end-of-life battery voltage. The MAX8887/MAX8888 use a P-channel MOSF ET pass transistor. Its dropout volt-age is a function of drain-to-source on-resistance (R DS(ON)) multiplied by the load current (see Typical Operating Characteristics ).V DROPOUT = V IN - V OUT = R DS(ON)✕I OUTChip InformationTRANSISTOR COUNT: 620PROCESS: BiCMOSMAX8887/MAX8888Low-Dropout, 300mA Linear Regulators in SOT23_______________________________________________________________________________________7Figure 1. Functional DiagramFigure 2. Power Operating Regions: Maximum Output Current vs. Input VoltageM A X 8887/M A X 8888Low-Dropout, 300mA Linear Regulators in SOT23Ma xim ca nnot a ssume responsibility for use of a ny circuitry other tha n circuitry entirely embodied in a Ma xim product. No circuit pa tent licenses a re implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.8_____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600©2000 Maxim Integrated ProductsPrinted USAis a registered trademark of Maxim Integrated Products.Package Information。
MAX4080SASA+T中文资料
Operating Temperature Range .........................-40°C to +125°C Junction Temperature ......................................................+150°C Storage Temperature Range .............................-65°C to +150°C Lead Temperature (soldering, 10s) .................................+300°C
RS+ 1 VCC 2 N.C. 3 GND 4
MAX4080
8 RS- RS+ 1 7 N.C. VCC 2 6 N.C. N.C. 3 5 OUT GND 4
MAX4081
8 RS7 REF1A 6 REF1B 5 OUT
μMAX/SO
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___________________________________________________________________Selector Guide________________General DescriptionThe MAX6316–MAX6322 family of microprocessor (µP)supervisory circuits monitors power supplies and microprocessor activity in digital systems. It offers sev-eral combinations of push/pull, open-drain, and bidirec-tional (such as Motorola 68HC11) reset outputs, along with watchdog and manual reset features. The Selector Guide below lists the specific functions available from each device. These devices are specifically designed to ignore fast negative transients on V CC . Resets are guaranteed valid for V CC down to 1V.These devices are available in 26 factory-trimmed reset threshold voltages (from 2.5V to 5V, in 100mV incre-ments), featuring four minimum power-on reset timeout periods (from 1ms to 1.12s), and four watchdog timeout periods (from 6.3ms to 25.6s). Thirteen standard ver-sions are available with an order increment requirement of 2500 pieces (see Standard Versions table); contact the factory for availability of other versions, which have an order increment requirement of 10,000 pieces.The MAX6316–MAX6322 are offered in a miniature 5-pin SOT23 package.________________________ApplicationsPortable Computers Computers ControllersIntelligent InstrumentsPortable/Battery-Powered Equipment Embedded Control Systems____________________________Features♦Small 5-Pin SOT23 Package♦Available in 26 Reset Threshold Voltages2.5V to 5V, in 100mV Increments ♦Four Reset Timeout Periods1ms, 20ms, 140ms, or 1.12s (min)♦Four Watchdog Timeout Periods6.3ms, 102ms, 1.6s, or 25.6s (typ) ♦Four Reset Output StagesActive-High, Push/Pull Active-Low, Push/Pull Active-Low, Open-Drain Active-Low, Bidirectional♦Guaranteed Reset Valid to V CC = 1V♦Immune to Short Negative V CC Transients ♦Low Cost♦No External ComponentsMAX6316–MAX63225-Pin µP Supervisory Circuits withWatchdog and Manual Reset________________________________________________________________Maxim Integrated Products 119-0496; Rev 7; 11/07_______________Ordering InformationOrdering Information continued at end of data sheet.*The MAX6318/MAX6319/MAX6321/MAX6322 feature two types of reset output on each device.Typical Operating Circuit and Pin Configurations appear at end of data sheet.For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,or visit Maxim’s website at .Specify lead-free by replacing “-T” with “+T” when ordering.ELECTRICAL CHARACTERISTICS(V CC = 2.5V to 5.5V, T A = -40°C to +125°C, unless otherwise noted. Typical values are at T A = +25°C.) (Note 1)M A X 6316–M A X 63225-Pin µP Supervisory Circuits with Watchdog and Manual Reset 2_______________________________________________________________________________________ABSOLUTE MAXIMUM RATINGSStresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.Voltage (with respect to GND)V CC ......................................................................-0.3V to +6V RESET (MAX6320/MAX6321/MAX6322 only)...... -0.3V to +6V All Other Pins.........................................-0.3V to (V CC + 0.3V)Input/Output Current, All Pins.............................................20mAContinuous Power Dissipation (T A = +70°C)SOT23-5 (derate 7.1mW/°C above +70°C)...............571mW Operating Temperature Range..........................-40°C to +125°C Junction Temperature......................................................+150°C Storage Temperature Range..............................-65°C to +160°C Lead Temperature (soldering, 10s).................................+300°CTH available in 100mV increments from 2.5V to 5V (see Table 1 at end of data sheet).Note 3:Guaranteed by design.MAX6316–MAX63225-Pin µP Supervisory Circuits withWatchdog and Manual Reset_______________________________________________________________________________________3Note 5:Measured from RESET V OL to (0.8 x V CC ), R LOAD = ∞.Note 6:WDI is internally serviced within the watchdog period if WDI is left unconnected.Note 7:The WDI input current is specified as the average input current when the WDI input is driven high or low. The WDI input is designed for a three-stated-output device with a 10µA maximum leakage current and capable of driving a maximum capac-itive load of 200pF. The three-state device must be able to source and sink at least 200µA when active.ELECTRICAL CHARACTERISTICS (continued)M A X 6316–M A X 63225-Pin µP Supervisory Circuits with Watchdog and Manual Reset 4_________________________________________________________________________________________________________________________________Typical Operating Characteristics(T A = +25°C, unless otherwise noted.)021*********-4020-20406080100MAX6316/MAX6317/MAX6318/MAX6320/MAX6321SUPPLY CURRENT vs. TEMPERATURETEMPERATURE (°C)S U P P L Y C U R R E N T (μA )302010504090807060100-40-20020406080100V CC FALLING TO RESET PROPAGATIONDELAY vs. TEMPERATURETEMPERATURE (°C)R E S E T P R O P A G A T I O N D E L A Y (μs )140180160240220200300280260320-40020-20406080100MAX6316/MAX6317/MAX6319/MAX6320/MAX6322MANUAL RESET TO RESETPROPAGATION DELAY vs. TEMPERATURETEMPERATURE (°C)P R O P A G A T I O N D E L A Y (n s )0.950.980.970.961.000.991.041.031.021.011.05-40-2020406080100NORMALIZED RESET TIMEOUT PERIOD vs. TEMPERATUREM A X 6316t o c 04TEMPERATURE (°C)N O R M A L I Z E D R E S E T T I M E O U T P E R I O D0.950.980.970.961.000.991.041.031.021.011.05-40-2020406080100MAX6316/MAX6317/MAX6318/MAX6320/MAX6321NORMALIZED WATCHDOG TIMEOUTPERIOD vs. TEMPERATUREM A X 6316t o c 05TEMPERATURE (°C)N O R M A L I Z E D W A T C H D O G T I M E O U T P E R I O D800101001000MAXIMUM V CC TRANSIENT DURATION vs. RESET THRESHOLD OVERDRIVE2010RESET THRESHOLD OVERDRIVE (mV) V RST - V CCT RA N S I E N T D U R A T I O N (μs )3050604070200ns/divMAX6316M/6318MH/6319MHBIDIRECTIONALPULLUP CHARACTERISTICSMAX6316–MAX63225-Pin µP Supervisory Circuits withWatchdog and Manual Reset_______________________________________________________________________________________5______________________________________________________________Pin DescriptionM A X 6316–M A X 63225-Pin µP Supervisory Circuits with Watchdog and Manual Reset 6______________________________________________________________________________________________________Detailed DescriptionA microprocessor’s (µP) reset input starts or restarts the µP in a known state. The reset output of the MAX6316–MAX6322 µP supervisory circuits interfaces with the reset input of the µP, preventing code-execution errors during power-up, power-down, and brownout condi-tions (see the Typical Operating Circuit ). The MAX6316/MAX6317/MAX6318/MAX6320/MAX6321 are also capa-ble of asserting a reset should the µP become stuck in an infinite loop.Reset OutputThe MAX6316L/MAX6318LH/MAX6319LH feature an active-low reset output, while the MAX6317H/MAX6318_H/MAX6319_H/MAX6321HP/MAX6322HP feature an active-high reset output. RESET is guaran-teed to be a logic low and RESET is guaranteed to be a logic high for V CC down to 1V.The MAX6316–MAX6322 assert reset when V CC is below the reset threshold (V RST ), when MR is pulled low (MAX6316_/MAX6317H/MAX6319_H/MAX6320P/MAX6322HP only), or if the WDI pin is not serviced withinthe watchdog timeout period (t WD ). Reset remains assert-ed for the specified reset active timeout period (t RP ) after V CC rises above the reset threshold, after MR transitions low to high, or after the watchdog timer asserts the reset (MAX6316_/MAX6317H/MAX6318_H/MAX6320P/MAX6321HP). After the reset active timeout period (t RP )expires, the reset output deasserts, and the watchdog timer restarts from zero (Figure 2).Figure 1. Functional DiagramFigure 2. Reset Timing DiagramMAX6316–MAX63225-Pin µP Supervisory Circuits withWatchdog and Manual Reset_______________________________________________________________________________________7Bidirectional R E S E T OutputThe MAX6316M/MAX6318MH/MAX6319MH are designed to interface with µPs that have bidirectional reset pins,such as the Motorola 68HC11. Like an open-drain output,these devices allow the µP or other devices to pull the bidirectional reset (RESET ) low and assert a reset condi-tion. However, unlike a standard open-drain output, it includes the commonly specified 4.7k Ωpullup resistor with a P-channel active pullup in parallel.This configuration allows the MAX6316M/MAX6318MH/MAX6319MH to solve a problem associated with µPs that have bidirectional reset pins in systems where sev-eral devices connect to RESET (F igure 3). These µPs can often determine if a reset was asserted by an exter-nal device (i.e., the supervisor IC) or by the µP itself (due to a watchdog fault, clock error, or other source),and then jump to a vector appropriate for the source of the reset. However, if the µP does assert reset, it does not retain the information, but must determine the cause after the reset has occurred.The following procedure describes how this is done in the Motorola 68HC11. In all cases of reset, the µP pulls RESET low for about four external-clock cycles. It then releases RESET , waits for two external-clock cycles,then checks RESET ’s state. If RESET is still low, the µP concludes that the source of the reset was external and, when RESET eventually reaches the high state, it jumps to the normal reset vector. In this case, stored-state information is erased and processing begins fromscratch. If, on the other hand, RESET is high after a delay of two external-clock cycles, the processor knows that it caused the reset itself and can jump to a different vector and use stored-state information to determine what caused the reset.A problem occurs with faster µPs; two external-clock cycles are only 500ns at 4MHz. When there are several devices on the reset line, and only a passive pullup resis-tor is used, the input capacitance and stray capacitance can prevent RESET from reaching the logic high state (0.8✕V CC ) in the time allowed. If this happens, all resets will be interpreted as external. The µP output stage is guaran-teed to sink 1.6mA, so the rise time can not be reduced considerably by decreasing the 4.7k Ωinternal pullup resistance. See Bidirectional Pullup Characteristics in the Typical Operating Characteristics .The MAX6316M/MAX6318MH/MAX6319MH overcome this problem with an active pullup FET in parallel with the 4.7k Ωresistor (F igures 4 and 5). The pullup transistor holds RESET high until the µP reset I/O or the supervisory circuit itself forces the line low. Once RESET goes below V PTH , a comparator sets the transition edge flip-flop, indi-cating that the next transition for RESET will be low to high. When RESET is released, the 4.7k Ωresistor pulls RESET up toward V CC . Once RESET rises above V PTH but is below (0.85 x V CC ), the active P-channel pullup turns on. Once RESET rises above (0.85 x V CC ) or the 2µs one-shot times out, the active pullup turns off. The parallel combination of the 4.7k Ωpullup and theFigure 3. MAX6316M/MAX6318MH/MAX6319MH Supports Additional Devices on the Reset BusM A X 6316–M A X 63225-Pin µP Supervisory Circuits with Watchdog and Manual Reset 8_______________________________________________________________________________________Figure 4. MAX6316/MAX6318MH/MAX6319MH Bidirectional Reset Output Functional DiagramMAX6316–MAX63225-Pin µP Supervisory Circuits withWatchdog and Manual Reset_______________________________________________________________________________________9P-channel transistor on-resistance quickly charges stray capacitance on the reset line, allowing RESET to transition from low to high within the required two elec-tronic-clock cycles, even with several devices on the reset line. This process occurs regardless of whether the reset was caused by V CC dipping below the reset threshold, the watchdog timing out, MR being asserted,or the µP or other device asserting RESET . The parts do not require an external pullup. To minimize supply cur-rent consumption, the internal 4.7k Ωpullup resistor dis-connects from the supply whenever the MAX6316M/MAX6318MH/MAX6319MH assert reset.Open-Drain R E S E T OutputThe MAX6320P/MAX6321HP/MAX6322HP have an active-low, open-drain reset output. This output struc-ture will sink current when RESET is asserted. Connect a pullup resistor from RESET to any supply voltage up to 6V (Figure 6). Select a resistor value large enough toregister a logic low (see Electrical Characteristics ), and small enough to register a logic high while supplying all input current and leakage paths connected to the RESET line. A 10k Ωpullup is sufficient in most applications.Manual-Reset InputThe MAX6316_/MAX6317H/MAX6319_H/MAX6320P/MAX6322HP feature a manual reset input. A logic low on MR asserts a reset. After MR transitions low to high, reset remains asserted for the duration of the reset timeout peri-od (t RP ). The MR input is connected to V CC through an internal 52k Ωpullup resistor and therefore can be left unconnected when not in use. MR can be driven with TTL-logic levels in 5V systems, with CMOS-logic levels in 3V systems, or with open-drain or open-collector output devices. A normally-open momentary switch from MR to ground can also be used; it requires no external debouncing circuitry. MR is designed to reject fast, negative-going transients (typically 100ns pulses). A 0.1µF capacitor from MR to ground provides additional noise immunity.The MR input pin is equipped with internal ESD-protection circuitry that may become forward biased. Should MR be driven by voltages higher than V CC , excessive current would be drawn, which would damage the part. F or example, assume that MR is driven by a +5V supply other than V CC . If V CC drops lower than +4.7V, MR ’s absolute maximum rating is violated [-0.3V to (V CC + 0.3V)], and undesirable current flows through the ESD structure from MR to V CC . To avoid this, use the same supply for MR as the supply monitored by V CC . This guarantees that the voltage at MR will never exceed V CC .Watchdog InputThe MAX6316_/MAX6317H/MAX6318_H/MAX6320P/MAX6321HP feature a watchdog circuit that monitors the µP’s activity. If the µP does not toggle the watchdog input (WDI) within the watchdog timeout period (t WD ),reset asserts. The internal watchdog timer is cleared by reset or by a transition at WDI (which can detect pulses as short as 50ns). The watchdog timer remains cleared while reset is asserted. Once reset is released, the timer begins counting again (Figure 7).The WDI input is designed for a three-stated output device with a 10µA maximum leakage current and the capability of driving a maximum capacitive load of 200pF.The three-state device must be able to source and sink at least 200µA when active. Disable the watchdog function by leaving WDI unconnected or by three-stating the driver connected to WDI. When the watchdog timer is left open circuited, the timer is cleared internally at intervals equal to 7/8 of the watchdog period.Figure 6. MAX6320P/MAX6321HP/MAX6322HP Open-Drain RESET Output Allows Use with Multiple SuppliesFigure 5. Bidirectional RESET Timing DiagramM A X 6316–M A X 63225-Pin µP Supervisory Circuits with Watchdog and Manual Reset 10______________________________________________________________________________________Applications InformationWatchdog Input CurrentThe WDI input is internally driven through a buffer and series resistor from the watchdog counter. For minimum watchdog input current (minimum overall power con-sumption), leave WDI low for the majority of the watch-dog timeout period. When high, WDI can draw as much as 160µA. Pulsing WDI high at a low duty cycle will reduce the effect of the large input current. When WDI is left unconnected, the watchdog timer is serviced within the watchdog timeout period by a low-high-low pulse from the counter chain.Negative-Going V CC TransientsThese supervisors are immune to short-duration, nega-tive-going V CC transients (glitches), which usually do not require the entire system to shut down. Typically,200ns large-amplitude pulses (from ground to V CC ) on the supply will not cause a reset. Lower amplitude puls-es result in greater immunity. Typically, a V CC transient that goes 100mV under the reset threshold and lasts less than 4µs will not trigger a reset. An optional 0.1µF bypass capacitor mounted close to V CC provides addi-tional transient immunity.Ensuring Valid Reset OutputsDown to V CC = 0The MAX6316_/MAX6317H/MAX6318_H/MAX6319_H/MAX6321HP/MAX6322HP are guaranteed to operate properly down to V CC = 1V. In applications that require valid reset levels down to V CC = 0, a pulldown resistor to active-low outputs (push/pull and bidirectional only,F igure 8) and a pullup resistor to active-high outputs(push/pull only, Figure 9) will ensure that the reset line is valid while the reset output can no longer sink orsource current. This scheme does not work with the open-drain outputs of the MAX6320/MAX6321/MAX6322.The resistor value used is not critical, but it must be large enough not to load the reset output when V CC is above the reset threshold. F or most applications,100k Ωis adequate.Watchdog Software Considerations(MAX6316/MAX6317/MAX6318/MAX6320/MAX6321)One way to help the watchdog timer monitor software execution more closely is to set and reset the watchdog input at different points in the program, rather than pulsing the watchdog input high-low-high or low-high-low. This technique avoids a stuck loop, in which the watchdog timer would continue to be reset inside the loop, keeping the watchdog from timing out.Figure 7. Watchdog Timing RelationshipFigure 9. Ensuring RESET Valid to V CC = 0 on Active-High Push/Pull OutputsFigure 8. Ensuring RESET Valid to V CC = 0 on Active-Low Push/Pull and Bidirectional OutputsMAX6316–MAX6322Watchdog and Manual Reset______________________________________________________________________________________11F igure 10 shows an example of a flow diagram where the I/O driving the watchdog input is set high at the beginning of the program, set low at the end of every subroutine or loop, then set high again when the pro-gram returns to the beginning. If the program should hang in any subroutine, the problem would be quickly corrected, since the I/O is continually set low and the watchdog timer is allowed to time out, causing a reset or interrupt to be issued. As described in the Watchdog Input Current section, this scheme results in higher time average WDI current than does leaving WDI low for the majority of the timeout period and periodically pulsing it low-high-low.Figure 10. Watchdog Flow Diagram__________________Pin ConfigurationsTypical Operating CircuitTable 2. Standard VersionsTable 1. Factory-Trimmed Reset ThresholdsM A X 6316–M A X 6322Watchdog and Manual ResetTable 3. Reset/Watchdog Timeout PeriodsMAX6316–MAX6322Watchdog and Manual Reset______________________________________________________________________________________13__Ordering Information (continued)a watchdog feature (see Selector Guide) are factory-trimmed to one of four watchdog timeout periods. Insert the letter corre-sponding to the desired watchdog timeout period (W, X, Y, or Z from Table 3) into the blank following the reset timeout suffix.TRANSISTOR COUNT: 191SUBSTRATE IS INTERNALLY CONNECTED TO V+Chip Informationdard versions only. The required order increment for nonstandard versions is 10,000 pieces. Contact factory for availability.M A X 6316–M A X 6322Watchdog and Manual Reset 14______________________________________________________________________________________Package Information(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,go to /packages .)M axim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a M axim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________15©2007 Maxim Integrated Productsis a registered trademark of Maxim Integrated Products, Inc.MAX6316–MAX6322 Watchdog and Manual ResetRevision History。