MAX471CSA+T中文资料
MAX471MAX472的中文资料大全
M A X471M A X472的中文资料大全(总4页)-本页仅作为预览文档封面，使用时请删除本页-MAX471/MAX472的特点、功能美国美信公司生产的精密高端电流检测放大器是一个系列化产品，有MAX471/MA X472、 MAX4172/MAX4173等。
它们均有一个电流输出端，可以用一个电阻来简单地实现以地为参考点的电流/电压的转换，并可工作在较宽电压内。
MAX471/MAX472具有如下特点：●具有完美的高端电流检测功能；●内含精密的内部检测电阻（MAX471）；●在工作温度范围内，其精度为2%；●具有双向检测指示，可监控充电和放电状态；●内部检测电阻和检测能力为3A，并联使用时还可扩大检测电流范围；●使用外部检测电阻可任意扩展检测电流范围（MAX472）；●最大电源电流为100μA；●关闭方式时的电流仅为5μA；●电压范围为3～36V；●采用8脚DIP/SO/STO三种封装形式。
MAX471/MAX472的引脚排列如图1所示，图2所示为其内部功能框图。
表1为MAX471/MAX472的引脚功能说明。
MAX471的电流增益比已预设为500μA/A，由于2kΩ的输出电阻（ROUT）可产生1V/A的转换，因此±3A时的满度值为3V.用不同的ROUT电阻可设置不同的满度电压。
但对于MAX471，其输出电压不应大于VRS+。
对于MAX472，则不能大于。
MAX471引脚图如图１所示，MAX472引脚图如图２所示。
MAX471/MAX472的引脚功能说明引脚名称功能MAX471MAX47211SHDN关闭端。
正常运用时连接到地。
当此端接高电平时，电源电流小于5μA2，3-RS+内部电流检测电阻电池（或电源端）。
“+”仅指示与SIGN输出有关的流动方向。
封装时已将2和3连在了一起-2空脚-3RG1增益电阻端。
通过增益设置电阻连接到电流检测电阻的电池端44GND地或电池负端55SIGN集电极开路逻辑输出端。
MAX3490CSA中文资料
元器件交易网
MAX3483/MAX3485/MAX3486/MAX3488/MAX3490/MAX3491
3.3V-Powered, 10Mbps and Slew-Rate-Limited True RS-485/RS-422 Transceivers
(MAX3483/MAX3485/MAX3486) o Current-Limiting and Thermal Shutdown for
Driver Overload Protection
______________Ordering Information
PART
TEMP. RANGE PIN-PACKAGE
Drivers are short-circuit current limited and are protected against excessive power dissipation by thermal shutdown circuitry that places the driver outputs into a high-impedance state. The receiver input has a fail-safe feature that guarantees a logic-high output if both inputs are open circuit.
________________________Applications
Low-Power RS-485/RS-422 Transceivers
Telecommunications
Transceivers for EMI-Sensitive Applications
Ratingrange：评级范围
Approval Standard And Recognized NO.CB Part Number Configuration :JY 102 K Y5P Y2(1) AC capacitors, safety(4) Type code: Y5P, Y5V,Y5U(1) (2) (3) (4) (5)(2) Rated capacitance (5) Class Y2(3) Tolerance on rated capacitance3JYH HSU Y2 SERIESINTRODUCTIONThese Ceramic Disc Capacitors are specifically designed for AC applications and meet the safety requirements of various safety standards agencies.These capacitors are ideal for acrossFEATURES:⊙Ideal for across the line applictions ⊙Compact size⊙Cost effective product⊙Safety standards recognized for AC applicationsCAPACITANCE AND DIMENSIONS:When ordering safety standard recognized ceramic capacitors please use the part number as noted aboveMARKINGJEC TYPE DESIGNATION or JD （ for Y1） 3 - DIGIT - SYSTEM : 472 = 4700 PF : 103 = 10000 PF CODE : K ＝Dimensions and Tolerance B ＝ 3.0 mm max for AA d ＝0.55 mm ±0.05 mm F ＝ 7.5 or 9.5 ±0.8 mm L ＝3 ~ 33 mm.◎ According as customer's request and size.Y2 , X1 ,AC300V , AC400V5新版1：新版2：加 KCWhether to put a KC logo according to customer's request按客户要求是否要加印 KC 标志MARKING : (FOR Y2)旧版6文件編號：P004 版 本：5 制訂日期：2014/02/20JECJY 102 KJEC JY 102 KJY 103 MJEC成品之編碼原則上以十五碼完成，亦以阿拉伯數字與英文字母混合編成，文件編號：P004碼至第十一碼與瓷片相同。
MAX4711CSE资料
General DescriptionThe MAX4711/MAX4712/MAX4713 are fault-protected,Rail-to-Rail ®, low-voltage analog switches featuring low on-resistance and guaranteed on-resistance flatness over the specified signal range. Due to the fault protection fea-ture the analog switch input (NO_ or NC_) and output (COM_) pins are not symmetrical. The fault protection fea-ture allows for the analog input to go beyond the plus or minus supplies without the device drawing excessive amounts of current from the analog inputs. When the ana-log inputs are driven beyond the supply rails when the switch is on, it will sense a fault and turn itself off and the analog switch output will be clamped to the same polarity supply as the input signal and will not go beyond the sup-ply rails. This feature protects any electronic circuitry con-nected to the output from excessive voltages present on the analog inputs.The MAX4711/MAX4712/MAX4713 are quad, single-pole/single-throw (SPST) analog switches. The MAX4711has four normally closed switches (NC), the MAX4712 has four normally open switches (NO), and the MAX4713 has two NO and two NC switches. Switching times are less than 125ns for t ON , and less than 80ns for t OFF . These switches operate from a single +2.7V to +11V supply or from dual ±2.7V to ±5.5V supplies. All digital inputs have +0.8V to +2.4V logic thresholds, ensuring both TTL and CMOS logic compatibility when using ±4.5V to ±5.5V or single +4.5V to +11V supplies.________________________ApplicationsCommunication Systems Battery-Operated Systems Signal Routing Test Equipment Data-AcquisitionIndustrial and Process Control Systems AvionicsRedundant/Backup SystemsFeatures♦Fault-Protected Analog Inputs ♦±12V Fault Protection with Power Off ♦±7V Fault Protection with ±5V Supplies ♦+12V and -7V Fault Protection with +5V Supply ♦+12V and -9V Fault Protection with +3V Supply ♦Fault-Protected Digital Inputs May Exceed V+Supply Rail ♦All Switches Off with Power Off ♦Rail-to-Rail Signal Handling♦Output Clamped to Appropriate Supply Voltages During Fault Condition ♦25Ω(max) R ON at +25°C♦1Ω(max) On-Resistance Match Between Channels ♦Single- and Dual-Supply Operation ♦Pin-Compatible with Industry-Standard MAX391/MAX392/MAX393♦TTL- and CMOS-Compatible Logic Inputs19-1907; Rev 1; 11/03MAX4711/MAX4712/MAX4713Fault-Protected, Low-Voltage, Quad SPST Analog Switches________________________________________________________________Maxim Integrated Products 1Pin Configurations/FunctionalDiagrams/Truth TablesFor price, delivery, and to place orders,please contact Maxim Distribution at 1-888-629-4642,or visit Maxim’s website at .Ordering InformationOrdering Information continued at end of data sheet.Pin Configurations/Functional Diagrams/Truth Tables continued at end of data sheet.Rail-to-Rail is a registered trademark of Nippon Motorola, Ltd.M A X 4711/M A X 4712/M A X 4713Fault-Protected, Low-Voltage, Quad SPST Analog SwitchesABSOLUTE MAXIMUM RATINGSELECTRICAL CHARACTERISTICS—Dual SuppliesStresses 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+...........................................................................-0.3V to +13V V-............................................................................-13V to +0.3V V+ to V-...................................................................-0.3V to +13V IN_...........................................................(V- + 12V) to (V- - 0.3V)COM_ (Note 1)......................................(V- - 0.3V) to (V+ + 0.3V)NO_, NC_ (Note 2)..................................(V+ - 12V) to (V- + 12V)Continuous Current into Any Terminal..............................±40mA Peak Current, into Any Terminal(pulsed at 1ms,10% duty cycle).................................±70mAContinuous Power Dissipation (T A = +70°C)16-Pin TSSOP (derate 5.70mW/°C above +70°C)...........457mW 16-Pin Narrow SO (derate 8.70mW/°C above +70°C).....696mW 16-Pin Plastic Dip (derate 10.53mW/°C above +70°C)...842mW Operating Temperature RangesMAX471_C_ E.....................................................0°C to +70°C MAX471_E_ E..................................................-40°C to +85°C Junction Temperature......................................................+150°C Storage Temperature Range.............................-65°C to +150°C Lead Temperature (soldering, 10s).................................+300°CNote 1:COM_ pin is not fault-protected. Signals on COM_ exceeding V+ or V- are clamped by internal diodes. Limit forward diodecurrent to maximum current rating.Note 2:NO_ and NC_ pins are fault-protected. Signals on NO_ or NC_ exceeding -12V to +12V may damage device. These limitsapply with V+ = V- = 0.MAX4711/MAX4712/MAX4713Fault-Protected, Low-Voltage, Quad SPST Analog Switches_______________________________________________________________________________________3ELECTRICAL CHARACTERISTICS—Dual Supplies (continued)M A X 4711/M A X 4712/M A X 4713Fault-Protected, Low-Voltage, Quad SPST Analog Switches 4_______________________________________________________________________________________ELECTRICAL CHARACTERISTICS—Dual Supplies (continued)(V+ = +4.5V to +5.5V, V- = -4.5V to -5.5V, V IH = +2.4V, V IL = +0.8V, GND = 0, T A = T MIN to T MAX , unless otherwise noted. Typical values are at T A = +25°C.) (Note 3)ELECTRICAL CHARACTERISTICS—+5V Single SupplyMAX4711/MAX4712/MAX4713Fault-Protected, Low-Voltage, Quad SPST Analog Switches_______________________________________________________________________________________5ELECTRICAL CHARACTERISTICS—+5V Single Supply (continued)M A X 4711/M A X 4712/M A X 4713Fault-Protected, Low-Voltage, Quad SPST Analog Switches 6_______________________________________________________________________________________ELECTRICAL CHARACTERISTICS—+3V Single Supply(V+ = +2.7V to +3.6V, V- = 0, V IH = +2.0V, V IL = +0.6V, GND = 0, T A = T MIN to T MAX , unless otherwise noted. Typical values are at T A = +25°C.) (Note 3)MAX4711/MAX4712/MAX4713Fault-Protected, Low-Voltage, Quad SPST Analog Switches_______________________________________________________________________________________7ELECTRICAL CHARACTERISTICS—+3V Single Supply (continued)(V+ = +2.7V to +3.6V, V- = 0, V IH = +2.0V, V IL = +0.6V, GND = 0, T A = T MIN to T MAX , unless otherwise noted. Typical values are at T A = +25°C.) (Note 3)Note 4:∆R ON = ∆R ON (MAX) - ∆R ON (MIN)Note 5:Leakage parameters are 100% tested at maximum-rated temperature and with dual supplies. Leakage parameters areguaranteed by correlation at +25°C.Note 6:Off-isolation = 20 log 10[V COM_/(V NO_or V NC_)], V COM_= output, V NO_or V NC_= input to off switch. Note 7:Between any two switches.M A X 4711/M A X 4712/M A X 4713Fault-Protected, Low-Voltage, Quad SPST Analog Switches 8_______________________________________________________________________________________Typical Operating Characteristics(V+ = +5V, V- = -5V, T A = +25°C, unless otherwise noted.)015105202530-5-1-2-4-312345ON-RESISTANCEvs. V COM (DUAL SUPPLIES)V COM (V)O N -R E S I S T A N C E (Ω)0510152025-5-1-3-2-412345ON-RESISTANCE vs. V COM AND TEMPERATURE (DUAL SUPPLIES)V COM (V)O N -R E S I S T A N C E (Ω)3020104050600 2.01.50.5 1.0 2.53.0 3.54.0 4.55.0ON-RESISTANCEvs. V COM (SINGLE SUPPLY)V COM (V)O N -R E S I S T A N C E (Ω)010520153025352.01.03.04.00.5 2.51.5 3.5 4.55.0ON-RESISTANCE vs. V COMAND TEMPERATURE (SINGLE SUPPLY)V COM (V)O N -R E S I S T A N C E (Ω)151052520454035305000.5 1.0 1.5 2.0 2.5 3.0ON-RESISTANCE vs. V COM AND TEMPERATURE (SINGLE SUPPLY)V COM (V)O N -R E S I S T A N C E (Ω)0.00010.010.00110.1100101000ON/OFF-LEAKAGE CURRENTvs. TEMPERATURETEMPERATURE (°C)L E A K A G E C U R R E N T (n A )-40-102060-30-200103040507080-1010030204050-6-20-4246CHARGE INJECTION vs. V COMV COM (V)C H A R G E (p C )0402080601001201401602.03.03.52.54.04.55.05.56.0TURN-ON/TURN-OFF TIMEvs. SUPPLY VOLTAGE (DUAL SUPPLIES)SUPPLY VOLTAGE (V)T I M E (n s )1005015030035025020040024567389101112TURN-ON/TURN-OFF TIMEvs. SUPPLY VOLTAGE (SINGLE SUPPLY)SUPPLY VOLTAGE (V)T I M E (n s )MAX4711/MAX4712/MAX4713Fault-Protected, Low-Voltage, Quad SPST Analog Switches_______________________________________________________________________________________90302010405060708090100-4010-15356085TURN-ON/TURN-OFF TIMEvs. TEMPERATURE (DUAL SUPPLIES)TEMPERATURE (°C)T I M E (n s )10050200150300250350-4010-15356085TURN-ON/TURN-OFF TIMEvs. TEMPERATURE (SINGLE SUPPLY)TEMPERATURE (°C)T I M E (n s )-40-20-300-1030201040-40-2020406080SUPPLY CURRENT vs. TEMPERATUREV IN = 0 OR 5VTEMPERATURE (°C)S U P P L Y C U R R E N T (µA )020406080100120140160012345SUPPLY CURRENT vs. INPUT VOLTAGEINPUT VOLTAGE (V)S U P P L Y C U R R EN T (A )0.90.71.51.31.11.92.11.72.32.4 5.4 6.43.44.47.48.49.410.4LOGIC LEVEL THRESHOLD vs. SUPPLY VOLTAGESUPPLY VOLTAGE (V)L O G I C V O L T A G E (V )-120-40-50-20-300-1010FREQUENCY RESPONSEFREQUENCY (MHz)R E S P O N S E (d B )0.0111010010000.1-110-100-90-80-70-601µs/divFAULT TURN-ON DELAY ANDRECOVERY TIME2V/div 02µs/divFAULT TURN-ON DELAY ANDRECOVERY TIME2V/div2V/divMAX4711/12/13 toc17NC_INPUTCOM_OUTPUT (300Ω LOAD)Typical Operating Characteristics (continued)(V+ = +5V, V- = -5V, T A = +25°C, unless otherwise noted.)M A X 4711/M A X 4712/M A X 4713Detailed DescriptionThe MAX4711/MAX4712/MAX4713 differ considerably from traditional fault-protection switches, with several advantages. First, they are constructed with two paral-lel FET’s allowing very low on-resistance. Second, they allow signals on the NC_ or NO_ pins that are within or slightly beyond the supply rails to be passed through the switch to the COM terminal, allowing rail-to-rail sig-nal operation. Third, when a signal on NC_ or NO_exceeds the supply rails by about 150mV (a fault con-dition) the voltage on COM_ is limited to the same polarity supply voltage. Operation is identical for both fault polarities.During a fault condition, the NO_ or NC_ input becomes high impedance regardless of the switch state or load resistance. If the switch is on, the COM_output current is supplied from V+ or V- by the clamp FET’s that are connected from COM to each supply.These FET’s can typically source or sink up to 15mA.When power is removed, the fault protection is still in effect. In this case, the NO_ or NC_ terminals are a vir-tual open circuit. The fault can be up to ±12V.The COM_ pins are not fault-protected, they act as nor-mal CMOS switch terminals. If a voltage source is con-nected to any COM_ pin, it should be limited to the supply voltages. Exceeding the supply voltage willcause high currents to flow through the ESD-protected diodes, possibly damaging the device (see Absolute Maximum Ratings ).Pin CompatibilityThese switches have identical pinouts to common non-fault-protected CMOS switches. Care should be exer-cised while considering them for direct replacements in existing printed circuit boards since only the NO_ and NC_ pins of each switch are fault-protected.Internal ConstructionInternal construction is shown in Figure 1, with the ana-log signal paths shown in bold. A single NO switch is shown; the NC configuration is identical except the logic-level translator is inverting. The analog switch is formed by the parallel combination of N-channel FET (N1) and P-channel FET (P1), which are driven on and off simultaneously according to the input fault condition and the logic-level state.Normal OperationTwo comparators continuously compare the voltage on the NO_ (or NC_) pin with V+ and V-. When the signal on NO_ or NC_ is between V+ and V- the switch acts normally, with FETs N1 and P1 turning on and off in response to IN_ signals. The parallel combination of N1 and P1 forms a low-value resistor between NO_ (orFault-Protected, Low-Voltage,10______________________________________________________________________________________NC_) and COM_ so that signals pass equally well in either direction.Positive Fault ConditionWhen the signal on NO_ (or NC_) exceeds V+ by about 150mV, the high-fault comparator output is high, turn-ing off FETs N1 and P1. This makes the NO_ (or NC_)input high impedance regardless of the switch state. If the switch state is “off”, all FETs are turned off and both NO_ (or NC_) and COM_ are high impedance. If the switch state is “on”, clamp FET P2 is turned on, sourc-ing current from V+ to COM_.Negative Fault ConditionWhen the signal on NO_ (or NC_) exceeds V- by about 150mV, the low-fault comparator output is high, turning off FETs N1 and P1. This makes the NO_ (or NC_) input high impedance regardless of the switch state. If the switch state is “off”, all FETs are turned off and both NO_ (or NC_) and COM_ are high impedance. If the switch state is “on”, clamp FET N2 is turned on, sinking current from COM_ to V-.Transient Fault Response and RecoveryWhen a fast rise-time or fall-time transient on NC_ or NO_ exceeds V+ or V-, the output (COM_) follows the input to the supply rail with only a few nanoseconds delay. This delay is due to the switch on-resistance and circuit capacitance to ground. When the input transient returns to within the supply rails, however, there is a 700ns output recovery delay time. These values depend on the COM_ output resistance and capaci-tance, and are not production tested or guaranteed.The delays are not dependent on the fault amplitude.Higher COM_ output resistance and capacitance increase recovery times.COM_ and IN_ PinsFETs N2 and P2 can source about ±15mA from V+ or V- to COM_ in the fault condition. Ensure that if the COM_ pin is connected to a low-resistance load, the absolute maximum current rating of 40mA is never exceeded both in normal and fault conditions.MAX4711/MAX4712/MAX4713Fault-Protected, Low-Voltage, Quad SPST Analog Switches______________________________________________________________________________________11Figure 1. Block DiagramM A X 4711/M A X 4712/M A X 4713The COM_ pins do not have fault protection. Reverse ESD-protection diodes are internally connected between COM_, and V+ and V-. If a signal on COM_exceeds V+ or V- by more than a diode drop, one of these diodes will conduct. The IN_ pin can exceed the positive supply voltage, but they can go below the neg-ative supply by only a diode drop. The maximum volt-age on these pins is 12V if operating from a single supply, regardless of the supply voltage (including 0volts), and if operating from dual supplies, the maxi-mum voltage is (V- + 12V).Fault-Protection Voltage and Power OffThe maximum fault voltage on the NC_ or NO_ pins is ±12V with power off.IN_ Logic-Level ThresholdsThe logic-level thresholds are CMOS and TTL compati-ble when using ±4.5V to ±5.5V or single +4.5V to +11V supplies. When using a +2.7V supply, the logic thresh-olds are V IH = 2.0V and V IL = 0.6V.Dual SuppliesThe MAX4711/MAX4712/MAX4713 operate with bipolar supplies between ±2.7V and ±5.5V. The V+ and V-supplies need not be symmetrical, but their difference should not exceed 11V.Single SupplyThe MAX4711/MAX4712/MAX4713 operate from a sin-gle supply between +2.7V and +11V when V- is con-nected to GND.Chip InformationTRANSISTOR COUNT: 463Fault-Protected, Low-Voltage, Quad SPST Analog SwitchesPin Configurations/Functional Diagrams/Truth Tables (continued)Ordering Information (continued)MAX4711/MAX4712/MAX4713Fault-Protected, Low-Voltage, Quad SPST Analog Switches______________________________________________________________________________________13Test Circuits/Timing DiagramsFigure 2. Switch Turn-On/Turn-Off TimesFigure 4. Charge InjectionFigure 3. MAX4713 Break-Before-Make IntervalM A X 4711/M A X 4712/M A X 4713Fault-Protected, Low-Voltage, Quad SPST Analog Switches 14______________________________________________________________________________________Figure 6. Frequency Response, Off-Isolation, and CrosstalkTest Circuits/Timing Diagrams (continued)Figure 5. COM_, NO_, NC_ CapacitanceMAX4711/MAX4712/MAX4713Fault-Protected, Low-Voltage, Quad SPST Analog Switches______________________________________________________________________________________15T S S O P 4.40m m .E PSPackage 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 A X 4711/M A X 4712/M A X 4713Fault-Protected, Low-Voltage, Quad SPST Analog Switches 16______________________________________________________________________________________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 .)MAX4711/MAX4712/MAX4713Fault-Protected, Low-Voltage, Quad SPST Analog SwitchesMaxim 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 ____________________17©2003 Maxim Integrated ProductsPrinted USAis a registered trademark of Maxim Integrated Products.P D I P N .E PSPackage 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 .)。
MEMORY存储芯片MAX1232CSA+T中文规格书
o Hot-Swap Input Structures on DE and RE
o Enhanced Slew-Rate Limiting Facilitates ErrorFree Data Transmission (MAX13080E–MAX13084E/MAX13089E)
UCSP is Taetrleadceommark of Maxim Integrated Products, Inc.
Security Systems
Instrumentation
Profibus
Features
o +5.0V Operation
o Extended ESD Protection for RS-485/RS-422 I/O Pins ±15kV Human Body Model
o Low-Current Shutdown Mode (Except MAX13081E/MAX13084E/MAX13087E)
o Pin-Selectable Full-/Half-Duplex Operation (MAX13089E)
o Phase Controls to Correct for Twisted-Pair Reversal (MAX13089E)
MAX13080ECPD+
0°C to +70°C 14 PDIP
MAX13080ECSD+
0°C to +70°C 14 SO
MAX13080EEPD+ -40°C to +85°C 14 PDIP
MAX1044CSA-T中文资料
19-4667; Rev 1; 7/94
Switched-Capacitor Voltage Converters
_______________General Description
The MAX1044 and ICL7660 are monolithic, CMOS switched-capacitor voltage converters that invert, double, divide, or multiply a positive input voltage. They are pin compatible with the industry-standard ICL7660 and LTC1044. Operation is guaranteed from 1.5V to 10V with no external diode over the full temperature range. They deliver 10mA with a 0.5V output drop. The MAX1044 has a BOOST pin that raises the oscillator frequency above the audio band and reduces external capacitor size requirements. The MAX1044/ICL7660 combine low quiescent current and high efficiency. Oscillator control circuitry and four power MOSFET switches are included on-chip. Applications include generating a -5V supply from a +5V logic supply to power analog circuitry. For applications requiring more power, the MAX660 delivers up to 100mA with a voltage drop of less than 0.65V.
MAX1487CSA中文资料
For pricing, delivery, and ordering information,please contact Maxim/Dallas Direct!at 1-888-629-4642, or visit Maxim’s website at .General DescriptionThe MAX481, MAX483, MAX485, MAX487–MAX491, and MAX1487 are low-power transceivers for RS-485 and RS-422 communication. Each part contains one driver and one receiver. The MAX483, MAX487, MAX488, and MAX489feature reduced slew-rate drivers that minimize EMI and reduce reflections caused by improperly terminated cables,thus allowing error-free data transmission up to 250kbps.The driver slew rates of the MAX481, MAX485, MAX490,MAX491, and MAX1487 are not limited, allowing them to transmit up to 2.5Mbps.These transceivers draw between 120µA and 500µA of supply current when unloaded or fully loaded with disabled drivers. Additionally, the MAX481, MAX483, and MAX487have a low-current shutdown mode in which they consume only 0.1µA. All parts operate from a single 5V supply.Drivers are short-circuit current limited and are protected against excessive power dissipation by thermal shutdown circuitry that places the driver outputs into a high-imped-ance state. The receiver input has a fail-safe feature that guarantees a logic-high output if the input is open circuit.The MAX487 and MAX1487 feature quarter-unit-load receiver input impedance, allowing up to 128 MAX487/MAX1487 transceivers on the bus. Full-duplex communi-cations are obtained using the MAX488–MAX491, while the MAX481, MAX483, MAX485, MAX487, and MAX1487are designed for half-duplex applications.________________________ApplicationsLow-Power RS-485 Transceivers Low-Power RS-422 Transceivers Level TranslatorsTransceivers for EMI-Sensitive Applications Industrial-Control Local Area Networks__Next Generation Device Features♦For Fault-Tolerant ApplicationsMAX3430: ±80V Fault-Protected, Fail-Safe, 1/4Unit Load, +3.3V, RS-485 TransceiverMAX3440E–MAX3444E: ±15kV ESD-Protected,±60V Fault-Protected, 10Mbps, Fail-Safe, RS-485/J1708 Transceivers♦For Space-Constrained ApplicationsMAX3460–MAX3464: +5V, Fail-Safe, 20Mbps,Profibus RS-485/RS-422 TransceiversMAX3362: +3.3V, High-Speed, RS-485/RS-422Transceiver in a SOT23 PackageMAX3280E–MAX3284E: ±15kV ESD-Protected,52Mbps, +3V to +5.5V, SOT23, RS-485/RS-422,True Fail-Safe ReceiversMAX3293/MAX3294/MAX3295: 20Mbps, +3.3V,SOT23, RS-855/RS-422 Transmitters ♦For Multiple Transceiver ApplicationsMAX3030E–MAX3033E: ±15kV ESD-Protected,+3.3V, Quad RS-422 Transmitters ♦For Fail-Safe ApplicationsMAX3080–MAX3089: Fail-Safe, High-Speed (10Mbps), Slew-Rate-Limited RS-485/RS-422Transceivers♦For Low-Voltage ApplicationsMAX3483E/MAX3485E/MAX3486E/MAX3488E/MAX3490E/MAX3491E: +3.3V Powered, ±15kV ESD-Protected, 12Mbps, Slew-Rate-Limited,True RS-485/RS-422 TransceiversMAX481/MAX483/MAX485/MAX487–MAX491/MAX1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers______________________________________________________________Selection Table19-0122; Rev 8; 10/03Ordering Information appears at end of data sheet.M A X 481/M A X 483/M A X 485/M A X 487–M A X 491/M A X 1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers 2_______________________________________________________________________________________ABSOLUTE MAXIMUM RATINGSSupply Voltage (V CC ).............................................................12V Control Input Voltage (RE , DE)...................-0.5V to (V CC + 0.5V)Driver Input Voltage (DI).............................-0.5V to (V CC + 0.5V)Driver Output Voltage (A, B)...................................-8V to +12.5V Receiver Input Voltage (A, B).................................-8V to +12.5V Receiver Output Voltage (RO).....................-0.5V to (V CC +0.5V)Continuous Power Dissipation (T A = +70°C)8-Pin Plastic DIP (derate 9.09mW/°C above +70°C)....727mW 14-Pin Plastic DIP (derate 10.00mW/°C above +70°C)..800mW 8-Pin SO (derate 5.88mW/°C above +70°C).................471mW14-Pin SO (derate 8.33mW/°C above +70°C)...............667mW 8-Pin µMAX (derate 4.1mW/°C above +70°C)..............830mW 8-Pin CERDIP (derate 8.00mW/°C above +70°C).........640mW 14-Pin CERDIP (derate 9.09mW/°C above +70°C).......727mW Operating Temperature RangesMAX4_ _C_ _/MAX1487C_ A...............................0°C to +70°C MAX4__E_ _/MAX1487E_ A.............................-40°C to +85°C MAX4__MJ_/MAX1487MJA...........................-55°C to +125°C Storage Temperature Range.............................-65°C to +160°C Lead Temperature (soldering, 10sec).............................+300°CDC ELECTRICAL CHARACTERISTICS(V CC = 5V ±5%, T A = T MIN to T MAX , unless otherwise noted.) (Notes 1, 2)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 V IN = -7VV IN = 12V V IN = -7V V IN = 12V Input Current (A, B)I IN2V TH k Ω48-7V ≤V CM ≤12V, MAX487/MAX1487R INReceiver Input Resistance -7V ≤V CM ≤12V, all devices except MAX487/MAX1487R = 27Ω(RS-485), Figure 40.4V ≤V O ≤2.4VR = 50Ω(RS-422)I O = 4mA, V ID = -200mV I O = -4mA, V ID = 200mV V CM = 0V-7V ≤V CM ≤12V DE, DI, RE DE, DI, RE MAX487/MAX1487,DE = 0V, V CC = 0V or 5.25VDE, DI, RE R = 27Ωor 50Ω, Figure 4R = 27Ωor 50Ω, Figure 4R = 27Ωor 50Ω, Figure 4DE = 0V;V CC = 0V or 5.25V,all devices except MAX487/MAX1487CONDITIONSk Ω12µA ±1I OZRThree-State (high impedance)Output Current at ReceiverV 0.4V OL Receiver Output Low Voltage 3.5V OH Receiver Output High Voltage mV 70∆V TH Receiver Input Hysteresis V -0.20.2Receiver Differential Threshold Voltage-0.2mA 0.25mA-0.81.01.55V OD2Differential Driver Output (with load)V 2V 5V OD1Differential Driver Output (no load)µA±2I IN1Input CurrentV 0.8V IL Input Low Voltage V 2.0V IH Input High Voltage V 0.2∆V OD Change in Magnitude of Driver Common-Mode Output Voltage for Complementary Output States V 0.2∆V OD Change in Magnitude of Driver Differential Output Voltage for Complementary Output States V 3V OC Driver Common-Mode Output VoltageUNITS MINTYPMAX SYMBOL PARAMETERMAX481/MAX483/MAX485/MAX487–MAX491/MAX1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers_______________________________________________________________________________________3SWITCHING CHARACTERISTICS—MAX481/MAX485, MAX490/MAX491, MAX1487(V CC = 5V ±5%, T A = T MIN to T MAX , unless otherwise noted.) (Notes 1, 2)DC ELECTRICAL CHARACTERISTICS (continued)(V CC = 5V ±5%, T A = T MIN to T MAX , unless otherwise noted.) (Notes 1, 2)ns 103060t PHLDriver Rise or Fall Time Figures 6 and 8, R DIFF = 54Ω, C L1= C L2= 100pF ns MAX490M, MAX491M MAX490C/E, MAX491C/E2090150MAX481, MAX485, MAX1487MAX490M, MAX491MMAX490C/E, MAX491C/E MAX481, MAX485, MAX1487Figures 6 and 8, R DIFF = 54Ω,C L1= C L2= 100pF MAX481 (Note 5)Figures 5 and 11, C RL = 15pF, S2 closedFigures 5 and 11, C RL = 15pF, S1 closed Figures 5 and 11, C RL = 15pF, S2 closed Figures 5 and 11, C RL = 15pF, S1 closed Figures 6 and 10, R DIFF = 54Ω,C L1= C L2= 100pFFigures 6 and 8,R DIFF = 54Ω,C L1= C L2= 100pF Figures 6 and 10,R DIFF = 54Ω,C L1= C L2= 100pF CONDITIONS ns 510t SKEW ns50200600t SHDNTime to ShutdownMbps 2.5f MAX Maximum Data Rate ns 2050t HZ Receiver Disable Time from High ns 103060t PLH 2050t LZ Receiver Disable Time from Low ns 2050t ZH Driver Input to Output Receiver Enable to Output High ns 2050t ZL Receiver Enable to Output Low 2090200ns ns 134070t HZ t SKD Driver Disable Time from High |t PLH - t PHL |DifferentialReceiver Skewns 4070t LZ Driver Disable Time from Low ns 4070t ZL Driver Enable to Output Low 31540ns51525ns 31540t R , t F 2090200Driver Output Skew to Output t PLH , t PHL Receiver Input to Output4070t ZH Driver Enable to Output High UNITS MIN TYP MAX SYMBOL PARAMETERFigures 7 and 9, C L = 100pF, S2 closed Figures 7 and 9, C L = 100pF, S1 closed Figures 7 and 9, C L = 15pF, S1 closed Figures 7 and 9, C L = 15pF, S2 closedM A X 481/M A X 483/M A X 485/M A X 487–M A X 491/M A X 1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers 4_______________________________________________________________________________________SWITCHING CHARACTERISTICS—MAX483, MAX487/MAX488/MAX489(V CC = 5V ±5%, T A = T MIN to T MAX , unless otherwise noted.) (Notes 1, 2)SWITCHING CHARACTERISTICS—MAX481/MAX485, MAX490/MAX491, MAX1487 (continued)(V CC = 5V ±5%, T A = T MIN to T MAX , unless otherwise noted.) (Notes 1, 2)3001000Figures 7 and 9, C L = 100pF, S2 closed Figures 7 and 9, C L = 100pF, S1 closed Figures 5 and 11, C L = 15pF, S2 closed,A - B = 2VCONDITIONSns 40100t ZH(SHDN)Driver Enable from Shutdown toOutput High (MAX481)nsFigures 5 and 11, C L = 15pF, S1 closed,B - A = 2Vt ZL(SHDN)Receiver Enable from Shutdownto Output Low (MAX481)ns 40100t ZL(SHDN)Driver Enable from Shutdown toOutput Low (MAX481)ns 3001000t ZH(SHDN)Receiver Enable from Shutdownto Output High (MAX481)UNITS MINTYP MAX SYMBOLPARAMETERt PLH t SKEW Figures 6 and 8, R DIFF = 54Ω,C L1= C L2= 100pFt PHL Figures 6 and 8, R DIFF = 54Ω,C L1= C L2= 100pFDriver Input to Output Driver Output Skew to Output ns 100800ns ns 2000MAX483/MAX487, Figures 7 and 9,C L = 100pF, S2 closedt ZH(SHDN)Driver Enable from Shutdown to Output High2502000ns2500MAX483/MAX487, Figures 5 and 11,C L = 15pF, S1 closedt ZL(SHDN)Receiver Enable from Shutdown to Output Lowns 2500MAX483/MAX487, Figures 5 and 11,C L = 15pF, S2 closedt ZH(SHDN)Receiver Enable from Shutdown to Output Highns 2000MAX483/MAX487, Figures 7 and 9,C L = 100pF, S1 closedt ZL(SHDN)Driver Enable from Shutdown to Output Lowns 50200600MAX483/MAX487 (Note 5) t SHDN Time to Shutdownt PHL t PLH , t PHL < 50% of data period Figures 5 and 11, C RL = 15pF, S2 closed Figures 5 and 11, C RL = 15pF, S1 closed Figures 5 and 11, C RL = 15pF, S2 closed Figures 5 and 11, C RL = 15pF, S1 closed Figures 7 and 9, C L = 15pF, S2 closed Figures 6 and 10, R DIFF = 54Ω,C L1= C L2= 100pFFigures 7 and 9, C L = 15pF, S1 closed Figures 7 and 9, C L = 100pF, S1 closed Figures 7 and 9, C L = 100pF, S2 closed CONDITIONSkbps 250f MAX 2508002000Maximum Data Rate ns 2050t HZ Receiver Disable Time from High ns 25080020002050t LZ Receiver Disable Time from Low ns 2050t ZH Receiver Enable to Output High ns 2050t ZL Receiver Enable to Output Low ns ns 1003003000t HZ t SKD Driver Disable Time from High I t PLH - t PHL I DifferentialReceiver SkewFigures 6 and 10, R DIFF = 54Ω,C L1= C L2= 100pFns 3003000t LZ Driver Disable Time from Low ns 2502000t ZL Driver Enable to Output Low ns Figures 6 and 8, R DIFF = 54Ω,C L1= C L2= 100pFns 2502000t R , t F 2502000Driver Rise or Fall Time ns t PLH Receiver Input to Output2502000t ZH Driver Enable to Output High UNITS MIN TYP MAX SYMBOL PARAMETERMAX481/MAX483/MAX485/MAX487–MAX491/MAX1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers_______________________________________________________________________________________530002.5OUTPUT CURRENT vs.RECEIVER OUTPUT LOW VOLTAGE525M A X 481-01OUTPUT LOW VOLTAGE (V)O U T P U T C U R R E N T (m A )1.515100.51.02.0203540450.90.1-50-252575RECEIVER OUTPUT LOW VOLTAGE vs.TEMPERATURE0.30.7TEMPERATURE (°C)O U T P U TL O W V O L T A G E (V )500.50.80.20.60.40100125-20-41.5 2.0 3.0 5.0OUTPUT CURRENT vs.RECEIVER OUTPUT HIGH VOLTAGE-8-16M A X 481-02OUTPUT HIGH VOLTAGE (V)O U T P U T C U R R E N T (m A )2.5 4.0-12-18-6-14-10-203.54.5 4.83.2-50-252575RECEIVER OUTPUT HIGH VOLTAGE vs.TEMPERATURE3.64.4TEMPERATURE (°C)O U T P UT H I G H V O L T A G E (V )0504.04.63.44.23.83.01001259000 1.0 3.0 4.5DRIVER OUTPUT CURRENT vs.DIFFERENTIAL OUTPUT VOLTAGE1070M A X 481-05DIFFERENTIAL OUTPUT VOLTAGE (V)O U T P U T C U R R E N T (m A )2.0 4.05030806040200.5 1.5 2.53.5 2.31.5-50-2525125DRIVER DIFFERENTIAL OUTPUT VOLTAGEvs. TEMPERATURE1.72.1TEMPERATURE (°C)D I F FE R E N T I A L O U T P U T V O L T A G E (V )751.92.21.62.01.8100502.4__________________________________________Typical Operating Characteristics(V CC = 5V, T A = +25°C, unless otherwise noted.)NOTES FOR ELECTRICAL/SWITCHING CHARACTERISTICSNote 1:All currents into device pins are positive; all currents out of device pins are negative. All voltages are referenced to deviceground unless otherwise specified.Note 2:All typical specifications are given for V CC = 5V and T A = +25°C.Note 3:Supply current specification is valid for loaded transmitters when DE = 0V.Note 4:Applies to peak current. See Typical Operating Characteristics.Note 5:The MAX481/MAX483/MAX487 are put into shutdown by bringing RE high and DE low. If the inputs are in this state for lessthan 50ns, the parts are guaranteed not to enter shutdown. If the inputs are in this state for at least 600ns, the parts are guaranteed to have entered shutdown. See Low-Power Shutdown Mode section.M A X 481/M A X 483/M A X 485/M A X 487–M A X 491/M A X 1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers 6___________________________________________________________________________________________________________________Typical Operating Characteristics (continued)(V CC = 5V, T A = +25°C, unless otherwise noted.)120008OUTPUT CURRENT vs.DRIVER OUTPUT LOW VOLTAGE20100M A X 481-07OUTPUT LOW VOLTAGE (V)O U T P U T C U R R E N T (m A )6604024801012140-1200-7-5-15OUTPUT CURRENT vs.DRIVER OUTPUT HIGH VOLTAGE-20-80M A X 481-08OUTPUT HIGH VOLTAGE (V)O U T P U T C U R R E N T (m A )-31-603-6-4-2024-100-40100-40-60-2040100120MAX1487SUPPLY CURRENT vs. TEMPERATURE300TEMPERATURE (°C)S U P P L Y C U R R E N T (µA )20608050020060040000140100-50-2550100MAX481/MAX485/MAX490/MAX491SUPPLY CURRENT vs. TEMPERATURE300TEMPERATURE (°C)S U P P L Y C U R R E N T (µA )257550020060040000125100-50-2550100MAX483/MAX487–MAX489SUPPLY CURRENT vs. TEMPERATURE300TEMPERATURE (°C)S U P P L Y C U R R E N T (µA )257550020060040000125MAX481/MAX483/MAX485/MAX487–MAX491/MAX1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers_______________________________________________________________________________________7______________________________________________________________Pin DescriptionFigure 1. MAX481/MAX483/MAX485/MAX487/MAX1487 Pin Configuration and Typical Operating CircuitM A X 481/M A X 483/M A X 485/M A X 487–M A X 491/M A X 1487__________Applications InformationThe MAX481/MAX483/MAX485/MAX487–MAX491 and MAX1487 are low-power transceivers for RS-485 and RS-422 communications. The MAX481, MAX485, MAX490,MAX491, and MAX1487 can transmit and receive at data rates up to 2.5Mbps, while the MAX483, MAX487,MAX488, and MAX489 are specified for data rates up to 250kbps. The MAX488–MAX491 are full-duplex trans-ceivers while the MAX481, MAX483, MAX485, MAX487,and MAX1487 are half-duplex. In addition, Driver Enable (DE) and Receiver Enable (RE) pins are included on the MAX481, MAX483, MAX485, MAX487, MAX489,MAX491, and MAX1487. When disabled, the driver and receiver outputs are high impedance.MAX487/MAX1487:128 Transceivers on the BusThe 48k Ω, 1/4-unit-load receiver input impedance of the MAX487 and MAX1487 allows up to 128 transceivers on a bus, compared to the 1-unit load (12k Ωinput impedance) of standard RS-485 drivers (32 trans-ceivers maximum). Any combination of MAX487/MAX1487 and other RS-485 transceivers with a total of 32 unit loads or less can be put on the bus. The MAX481/MAX483/MAX485 and MAX488–MAX491 have standard 12k ΩReceiver Input impedance.Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers 8_______________________________________________________________________________________Figure 2. MAX488/MAX490 Pin Configuration and Typical Operating CircuitFigure 3. MAX489/MAX491 Pin Configuration and Typical Operating CircuitMAX483/MAX487/MAX488/MAX489:Reduced EMI and ReflectionsThe MAX483 and MAX487–MAX489 are slew-rate limit-ed, minimizing EMI and reducing reflections caused by improperly terminated cables. Figure 12 shows the dri-ver output waveform and its Fourier analysis of a 150kHz signal transmitted by a MAX481, MAX485,MAX490, MAX491, or MAX1487. High-frequency har-monics with large amplitudes are evident. Figure 13shows the same information displayed for a MAX483,MAX487, MAX488, or MAX489 transmitting under the same conditions. Figure 13’s high-frequency harmonics have much lower amplitudes, and the potential for EMI is significantly reduced.MAX481/MAX483/MAX485/MAX487–MAX491/MAX1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers_______________________________________________________________________________________9_________________________________________________________________Test CircuitsFigure 4. Driver DC Test Load Figure 5. Receiver Timing Test LoadFigure 6. Driver/Receiver Timing Test Circuit Figure 7. Driver Timing Test LoadM A X 481/M A X 483/M A X 485/M A X 487–M A X 491/M A X 1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers 10_______________________________________________________Switching Waveforms_________________Function Tables (MAX481/MAX483/MAX485/MAX487/MAX1487)Figure 8. Driver Propagation DelaysFigure 9. Driver Enable and Disable Times (except MAX488 and MAX490)Figure 10. Receiver Propagation DelaysFigure 11. Receiver Enable and Disable Times (except MAX488and MAX490)Table 1. TransmittingTable 2. ReceivingLow-Power Shutdown Mode (MAX481/MAX483/MAX487)A low-power shutdown mode is initiated by bringing both RE high and DE low. The devices will not shut down unless both the driver and receiver are disabled.In shutdown, the devices typically draw only 0.1µA of supply current.RE and DE may be driven simultaneously; the parts 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 600ns, the parts are guaranteed to enter shutdown.For the MAX481, MAX483, and MAX487, the t ZH and t ZL enable times assume the part was not in the low-power shutdown state (the MAX485/MAX488–MAX491and MAX1487 can not be shut down). The t ZH(SHDN)and t ZL(SHDN)enable times assume the parts were shut down (see Electrical Characteristics ).It takes the drivers and receivers longer to become enabled from the low-power shutdown state (t ZH(SHDN ), t ZL(SHDN)) than from the operating mode (t ZH , t ZL ). (The parts are in operating mode if the –R —E –,DE inputs equal a logical 0,1 or 1,1 or 0, 0.)Driver Output ProtectionExcessive output current and power dissipation caused by faults or by bus contention are prevented by two mechanisms. A foldback current limit on the output stage provides immediate protection against short cir-cuits over the whole common-mode voltage range (see Typical Operating Characteristics ). In addition, a ther-mal shutdown circuit forces the driver outputs into a high-impedance state if the die temperature rises excessively.Propagation DelayMany digital encoding schemes depend on the differ-ence between the driver and receiver propagation delay times. Typical propagation delays are shown in Figures 15–18 using Figure 14’s test circuit.The difference in receiver delay times, | t PLH - t PHL |, is typically under 13ns for the MAX481, MAX485,MAX490, MAX491, and MAX1487 and is typically less than 100ns for the MAX483 and MAX487–MAX489.The driver skew times are typically 5ns (10ns max) for the MAX481, MAX485, MAX490, MAX491, and MAX1487, and are typically 100ns (800ns max) for the MAX483 and MAX487–MAX489.MAX481/MAX483/MAX485/MAX487–MAX491/MAX1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers______________________________________________________________________________________1110dB/div0Hz5MHz500kHz/div10dB/div0Hz5MHz500kHz/divFigure 12. Driver Output Waveform and FFT Plot of MAX481/MAX485/MAX490/MAX491/MAX1487 Transmitting a 150kHz SignalFigure 13. Driver Output Waveform and FFT Plot of MAX483/MAX487–MAX489 Transmitting a 150kHz SignalM A X 481/M A X 483/M A X 485/M A X 487–M A X 491/M A X 1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers 12______________________________________________________________________________________V CC = 5V T A = +25°CV CC = 5V T A = +25°CV CC = 5V T A = +25°CV CC = 5V T A = +25°CFigure 14. Receiver Propagation Delay Test CircuitFigure 15. MAX481/MAX485/MAX490/MAX491/MAX1487Receiver t PHLFigure 16. MAX481/MAX485/MAX490/MAX491/MAX1487Receiver t PLHPHL Figure 18. MAX483, MAX487–MAX489 Receiver t PLHLine Length vs. Data RateThe RS-485/RS-422 standard covers line lengths up to 4000 feet. For line lengths greater than 4000 feet, see Figure 23.Figures 19 and 20 show the system differential voltage for the parts driving 4000 feet of 26AWG twisted-pair wire at 110kHz into 120Ωloads.Typical ApplicationsThe MAX481, MAX483, MAX485, MAX487–MAX491, and MAX1487 transceivers are designed for bidirectional data communications on multipoint bus transmission lines.Figures 21 and 22 show typical network applications circuits. These parts can also be used as line repeaters, with cable lengths longer than 4000 feet, as shown in Figure 23.To minimize reflections, the line should be terminated at both ends in its characteristic impedance, and stub lengths off the main line should be kept as short as possi-ble. The slew-rate-limited MAX483 and MAX487–MAX489are more tolerant of imperfect termination.MAX481/MAX483/MAX485/MAX487–MAX491/MAX1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers______________________________________________________________________________________13DIV Y -V ZRO5V 0V1V0V -1V5V 0V2µs/divFigure 19. MAX481/MAX485/MAX490/MAX491/MAX1487 System Differential Voltage at 110kHz Driving 4000ft of Cable Figure 20. MAX483, MAX487–MAX489 System Differential Voltage at 110kHz Driving 4000ft of CableFigure 21. MAX481/MAX483/MAX485/MAX487/MAX1487 Typical Half-Duplex RS-485 NetworkM A X 481/M A X 483/M A X 485/M A X 487–M A X 491/M A X 1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers 14______________________________________________________________________________________Figure 22. MAX488–MAX491 Full-Duplex RS-485 NetworkFigure 23. Line Repeater for MAX488–MAX491Isolated RS-485For isolated RS-485 applications, see the MAX253 and MAX1480 data sheets.MAX481/MAX483/MAX485/MAX487–MAX491/MAX1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers______________________________________________________________________________________15_______________Ordering Information_________________Chip TopographiesMAX481/MAX483/MAX485/MAX487/MAX1487N.C. RO 0.054"(1.372mm)0.080"(2.032mm)DE DIGND B N.C.V CCARE * Contact factory for dice specifications.__Ordering Information (continued)M A X 481/M A X 483/M A X 485/M A X 487–M A X 491/M A X 1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers 16______________________________________________________________________________________TRANSISTOR COUNT: 248SUBSTRATE CONNECTED TO GNDMAX488/MAX490B RO 0.054"(1.372mm)0.080"(2.032mm)N.C. DIGND Z A V CCYN.C._____________________________________________Chip Topographies (continued)MAX489/MAX491B RO 0.054"(1.372mm)0.080"(2.032mm)DE DIGND Z A V CCYREMAX481/MAX483/MAX485/MAX487–MAX491/MAX1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers______________________________________________________________________________________17Package 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 .)S O I C N .E P SM A X 481/M A X 483/M A X 485/M A X 487–M A X 491/M A X 1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers 18______________________________________________________________________________________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 .)MAX481/MAX483/MAX485/MAX487–MAX491Low-Power, Slew-Rate-Limited RS-485/RS-422 TransceiversMaxim 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 ____________________19©2003 Maxim Integrated ProductsPrinted USAis a registered trademark of Maxim Integrated Products.M A X 481/M A X 483/M A X 485/M A X 487–M A X 491/M A X 1487P D I P N .E PSPackage 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 .)。
巴克莱海尔471TC和471ST高压力高速放流管子产品简介（2001年9月）说明书
Parker 471TC and 471ST High-Impulse HosesBulletin No.4480-B51-US September, 2001Product Bulletin• One-half SAE 100R2 minimum bend radius• Exceeds SAE 100R16 and European EN857 T ype 2SC requirements*• Specially engineered TC and ST covers prolong hose lifeWe Keep Ideas Flowing ™Hose Products Division Parker Hannifin Corporation 30240 Lakeland Blvd.Wickliffe, Ohio 44092Phone:(440) 943-5700Fax:(440) Bulletin 4480-B51-US GL 7.5M 9/01 ©2001 Parker Hannifin CorporationNOTE:The silver die ring must be used when crimping 43 Series Parkrimp fittings onto 471TC and 471ST hoses.*-4 sizes do not meet EN857 T ype 2SC requirements.Distributed by:DANGERFAILURE OR IMPROPER SELECTION OR IMPROPER USE OF THE PRODUCTS AND/OR SYSTEMS DESCRIBED HEREIN OR RELA TED ITEMS CAN CAUSE DEA TH, PERSONAL INJURY AND PROPERTY DAMAGE.B efore selecting or using any Parker hose or fittings or related accessories, it is important that you read and follow Parker Safety Guide for Selecting and Using Hoses, Fittings, and Related Accessories (Parker Publication No.4400-B.1).!Whether your business is construction, refuse and recycling, railroad equipment,or the energy industry , Parker 471TC and 471ST are the hoses designed to meet your customers’high-pressure needs…around the world.Superior flexibility,tight bend radius — Designed for plumbing hydraulic lines in tight spaces, Parker 471TC and 471ST feature a one-half SAE 100R2 minimum bend radius which equates to easy installation and less hose required.Y our choice of covers — Parker 471TC comes with our T ough Cover compound, while 471ST features Parker’s Super T ough cover for the ultimate in abrasion resistance.So you can select your level of abrasion resistance.Increased pressure — Engineered to handle high impulse and pressure applications, Parker 471TC and 471ST have a 15% to 35% higher working pressure versus standard SAE 100R2 hose.Unmatched Parker quality and service — When you order 471TC and 471ST hoses, you get the finest hose plus the full support of Parker’s network of service centers, training programs, prototyping, field representatives, and more.In short,you get the best value.except for a high abrasion-resistant Super T ough polymeric cover.Applications and temperature ranges• Petroleum-based hydraulic fluids and lubrication oils within a temperature range of - 40°F to +212°F (-40°C to +100°C).• Water, water/oil emulsion, and water/glycol hydraulic fluids up to +185°F (+85°C).• Air up to +158°F (+70°C).Parkrimp compatibleParker 43 Series crimp fittings,471TC hose,and 471ST hose are compatible with the Parkrimpsystem of crimpers.So assembly is as simple as 1-2-3.New Parker 471TC and 471ST are the hoses that get you into the tight spots.Super T ough polymeric coverBold layline makes hoseidentification easyMSHA-accepted T ough Cover Multiple layers of steel wire reinforcementNitrile-based rubber inner tube。
MAX774中文资料
SHDN REF
FB REF GND OUT
MAX774 MAX775 MAX776
7 6 5
DIP/SO
________________________________________________________________ Maxim Integrated Products
1
Call toll free 1-800-998-8800 for free samples or literature.
ELECTRICAL CHARACTERISTICS
PARAMETER V+ Input Voltage Range SYMBOL V+
(V+ = 5V, ILOAD = 0mA, CREF = 0.1µF, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) CONDITIONS V+ = 16.5V, SHDN ≤ 0.4V (operating) Supply Current V+ = 10V, SHDN ≥ 1.6V (shutdown) V+ = 16.5V, SHDN ≥ 1.6V (shutdown) FB Trip Point 3V ≤ V+ ≤ 16.5V MAX77_C FB Input Current IFB MAX77_E MAX77_M MAX774 Output Voltage VOUT MAX775 MAX776 MAX77_C Reference Voltage VREF IREF = 0µA MAX77_E MAX77_M REF Load Regulation REF Line Regulation Output Voltage Line Regulation (Circuit of Figure 2— Bootstrapped) Output Voltage Load Regulation (Circuit of Figure 2— Bootstrapped) 0µA ≤ IREF ≤ 100µA 3V ≤ V+ ≤ 16.5V MAX774, 4V ≤ V+ ≤ 15V, ILOAD = 0.5A MAX775, 4V ≤ V+ ≤ 8V, ILOAD = 0.2A MAX776, 4V ≤ V+ ≤ 6V, ILOAD = 0.1A MAX774, 0A ≤ ILOAD ≤ 1A, V+ = 5V MAX775, 0mA ≤ ILOAD ≤ 500mA, V+ = 5V MAX776, 0mA ≤ ILOAD ≤ 400mA, V+ = 5V MAX77_C/E MAX77_M -4.80 -11.52 -14.40 1.4700 1.4625 1.4550 -5 -12 -15 1.5 1.5 1.5 4 4 40 0.035 0.088 0.137 1.5 1.5 1.0 mV/A mV/V -10 2 4 10 ±50 ±70 ±90 -5.20 -12.48 -15.60 1.5300 1.5375 1.5450 10 15 100 mV µV/V V V nA mV MIN 3.0 TYP MAX 16.5 100 5 µA UNITS V
君耀压敏电阻BK471KD07
890
680KD07 680KD07J 40 56
68(61~75) 2.5 135 250 500 3.6 7.0 0.02
740
820KD07 820KD07J 50 65
82(74~90) 10 135 1200 1750 5.5 10.0 0.25
600
101KD07 101KD07J 60 85 100(90~110) 10 165 1200 1750 6.5 12.0 0.25
7Φ SERIES
Part Number
Maximum Allowable Voltage
Maximum Varistor Voltage Clamping
Voltage
Withstanding Surge Current
Maximum Energy
(10/1000ȝs)
Rated Power
Typical Capacitance (Reference)
the standard impulse current (8/20ȝsec.) applied one time.
Vb at 20ć - Vb at 70ć u 1 u 100 (% ć)
Vb at 20ć
50
The change of Vb shall be measured after the impulse listed below is
115
471KD07 471KD07J 300 385 470(423~517) 10 775 1200 1750 30.0 42.0 0.25
105
511KD07 511KD07J 320 415 510(459~561) 10 845 1200 1750 30.0 45.0 0.25
MAX1771CSA中文资料
8 SO Dice* 8 Plastic DIP 8 SO 8 CERDIP**
* Contact factory for dice specifications. ** Contact factory for availability and processing to MIL-STD-883B.
MIN
MAX1771 (internal feedback resistors)
2.0
Input Voltage Range
MAX1771C/E (external resistors)
3.0
MAX1771MJA (external resistors)
3.1
Minimum Start-Up Voltage Supply Current
8 CS 7 GND 6 AGND 5 REF
________________________________________________________________ Maxim Integrated Products 1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at .
Operating Temperature Ranges MAX1771C_ A .....................................................0°C to +70°C MAX1771E_ A ..................................................-40°C to +85°C MAX1771MJA ................................................-55°C to +125°C
MAX471 电流检测集成电路
____________________________Features
o Complete High-Side Current Sensing o Precision Internal Sense Resistor (MAX471) o 2% Accuracy Over Temperature o Monitors Both Charge and Discharge o 3A Sense Capability with Internal Sense Resistor (MAX471) o Higher Current-Sense Capability with External Sense Resistor (MAX472) o 100µA Max Supply Current o 5µA Max Shutdown Mode o 3V to 36V Supply Operation o 8-Pin DIP/SO Packages
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.
MAX1978中文数据手册
用于Peltier模块的集成温度控制器概论MAX1978 / MAX1979是用于Peltier热电冷却器（TEC）模块的最小, 最安全, 最精确完整的单芯片温度控制器。
片上功率FET和热控制环路电路可最大限度地减少外部元件, 同时保持高效率。
可选择的500kHz / 1MHz开关频率和独特的纹波消除方案可优化元件尺寸和效率, 同时降低噪声。
内部MOSFET的开关速度经过优化, 可降低噪声和EMI。
超低漂移斩波放大器可保持±0.001°C的温度稳定性。
直接控制输出电流而不是电压, 以消除电流浪涌。
独立的加热和冷却电流和电压限制提供最高水平的TEC保护。
MAX1978采用单电源供电, 通过在两个同步降压调节器的输出之间偏置TEC, 提供双极性±3A输出。
真正的双极性操作控制温度, 在低负载电流下没有“死区”或其他非线性。
当设定点非常接近自然操作点时, 控制系统不会捕获, 其中仅需要少量的加热或冷却。
模拟控制信号精确设置TEC 电流。
MAX1979提供高达6A的单极性输出。
提供斩波稳定的仪表放大器和高精度积分放大器, 以创建比例积分（PI）或比例积分微分（PID）控制器。
仪表放大器可以连接外部NTC或PTC热敏电阻, 热电偶或半导体温度传感器。
提供模拟输出以监控TEC温度和电流。
此外, 单独的过热和欠温输出表明当TEC温度超出范围时。
片上电压基准为热敏电阻桥提供偏置。
MAX1978 / MAX1979采用薄型48引脚薄型QFN-EP 封装, 工作在-40°C至+ 85°C温度范围。
采用外露金属焊盘的耐热增强型QFN-EP封装可最大限度地降低工作结温。
评估套件可用于加速设计。
应用光纤激光模块典型工作电路出现在数据手册的最后。
WDM, DWDM激光二极管温度控制光纤网络设备EDFA光放大器电信光纤接口ATE特征♦尺寸最小, 最安全, 最精确完整的单芯片控制器♦片上功率MOSFET-无外部FET♦电路占用面积<0.93in2♦回路高度<3mm♦温度稳定性为0.001°C♦集成精密积分器和斩波稳定运算放大器♦精确, 独立的加热和冷却电流限制♦通过直接控制TEC电流消除浪涌♦可调节差分TEC电压限制♦低纹波和低噪声设计♦TEC电流监视器♦温度监控器♦过温和欠温警报♦双极性±3A输出电流（MAX1978）♦单极性+ 6A输出电流（MAX1979）订购信息* EP =裸焊盘。
电流传感放大器MAX471工作原理及在智能密码锁中的应用_王宽仁
的输出电压 Vou t 值 , 结 果如表 3 所示。其电 流/ 电压变换曲线如图
4 所示 。分析图 4 , 可以
得到如下结论 :
(1)总体来看 , 实
测值小于理论值 , 而且
随着被测电流增加 , 这
种误差有增加趋势 。这是因为线路直流电
阻 、 电源滤波电容容量及电源未经稳压所
致。
(2)被测电流在 ILoad =900mA 时 , 误差 最大 , 此时最大误差电流 ΔILoad =8mA 。
→
应 用与 实 践
电流传感放大器MAX 471
摘 要 介绍了电流传感放大器 MAX471 的引脚 、 参数 及功能 , 详细叙述了其工作原理 , 给出了在智能密码锁中的应 用电路及其参数计算 , 最后分析了其测量精度及最大误差 。分 析结果对该器件实际应用具有指导意义 。
关键词 电流传感放大器 M AX471 安全性 可靠性 测量精度
工 作锁具两部分组成 , 二者 异地放置 。智能监控器提供电子锁具所需的电源 , 同时接收电 子锁具发送的状态信息 。 在智能密码锁设计时采用了线路复 用技术使电能供给和信息传输共用一根二芯电缆 。对流过电 缆的供电电流连续检测 , 是防止人为破坏 , 提高智能密码锁安 全性的重要保证 。
以上分析表明 , 用电流传感放大器
M AX471 测量流过通信电缆的供电电流及
电磁线圈的驱动电流 , 具有测量准确度高 ,
电路设计简单等特点 , 从而大大提高了智能
密码锁的安全性 、可靠性 。因此 , MAX471有
着广泛的应用前景 。
◇ 测试结果
根据上述计算的电路参数 , 将其应用到 智能密码锁电路(图 3 所示)中 , 并实际测量
电子锁具的开锁是通过驱动电磁执行机构实现的 , 电磁 执行机构是一个感性功率元件 , 其核心是一只电磁线圈 。在长 期使用过程中 , 由于环境 、绝缘等因素极易造成匝间击穿 , 引 起驱动电流增加 。如果能及时发现驱动电流的变化 , 并采取相 应措施 , 可以大大提高智能密码锁的可靠性 。因此 , 本文采用 了电流传感放大器 M AX471 实时不断地检测流过电缆的供 电电流和电磁线圈的驱动电流 , 提高了电流检测的精确度 , 使 得智能密码锁具有很高的安全性 、可靠性 。
MC34072A中文资料
Table 1. Single OpIO (mV) Max TCVIO (µV/°C) (µV/ C) Typ IIO (nA) Max Avol (V/mV) Min BW (Av = 1) (MHz) Typ SR (Av = 1) (V/µs) Typ Supply Voltage (V) Min Max Description
Motorola Master Selection Guide
4.1–1
Analog and Interface Integrated Circuits
元器件交易网
Operational Amplifiers
Motorola offers a broad line of bipolar operational amplifiers to meet a wide range of applications. From low–cost industry–standard types to high precision circuits, the span encompasses a large range of performance capabilities. These Analog integrated circuits are available as single, dual and quad monolithic devices in a variety of temperature ranges and package styles. Most devices may be obtained in unencapsulated ‘‘chip’’ form as well. For price and delivery information on chips, please contact your Motorola Sales Representative or Distributor.
MAX485CSA+中文资料
For pricing, delivery, and ordering information,please contact Maxim/Dallas Direct!at 1-888-629-4642, or visit Maxim’s website at .General DescriptionThe MAX481, MAX483, MAX485, MAX487–MAX491, and MAX1487 are low-power transceivers for RS-485 and RS-422 communication. Each part contains one driver and one receiver. The MAX483, MAX487, MAX488, and MAX489feature reduced slew-rate drivers that minimize EMI and reduce reflections caused by improperly terminated cables,thus allowing error-free data transmission up to 250kbps.The driver slew rates of the MAX481, MAX485, MAX490,MAX491, and MAX1487 are not limited, allowing them to transmit up to 2.5Mbps.These transceivers draw between 120µA and 500µA of supply current when unloaded or fully loaded with disabled drivers. Additionally, the MAX481, MAX483, and MAX487have a low-current shutdown mode in which they consume only 0.1µA. All parts operate from a single 5V supply.Drivers are short-circuit current limited and are protected against excessive power dissipation by thermal shutdown circuitry that places the driver outputs into a high-imped-ance state. The receiver input has a fail-safe feature that guarantees a logic-high output if the input is open circuit.The MAX487 and MAX1487 feature quarter-unit-load receiver input impedance, allowing up to 128 MAX487/MAX1487 transceivers on the bus. Full-duplex communi-cations are obtained using the MAX488–MAX491, while the MAX481, MAX483, MAX485, MAX487, and MAX1487are designed for half-duplex applications.________________________ApplicationsLow-Power RS-485 Transceivers Low-Power RS-422 Transceivers Level TranslatorsTransceivers for EMI-Sensitive Applications Industrial-Control Local Area Networks__Next Generation Device Features♦For Fault-Tolerant ApplicationsMAX3430: ±80V Fault-Protected, Fail-Safe, 1/4Unit Load, +3.3V, RS-485 TransceiverMAX3440E–MAX3444E: ±15kV ESD-Protected,±60V Fault-Protected, 10Mbps, Fail-Safe, RS-485/J1708 Transceivers♦For Space-Constrained ApplicationsMAX3460–MAX3464: +5V, Fail-Safe, 20Mbps,Profibus RS-485/RS-422 TransceiversMAX3362: +3.3V, High-Speed, RS-485/RS-422Transceiver in a SOT23 PackageMAX3280E–MAX3284E: ±15kV ESD-Protected,52Mbps, +3V to +5.5V, SOT23, RS-485/RS-422,True Fail-Safe ReceiversMAX3293/MAX3294/MAX3295: 20Mbps, +3.3V,SOT23, RS-855/RS-422 Transmitters ♦For Multiple Transceiver ApplicationsMAX3030E–MAX3033E: ±15kV ESD-Protected,+3.3V, Quad RS-422 Transmitters ♦For Fail-Safe ApplicationsMAX3080–MAX3089: Fail-Safe, High-Speed (10Mbps), Slew-Rate-Limited RS-485/RS-422Transceivers♦For Low-Voltage ApplicationsMAX3483E/MAX3485E/MAX3486E/MAX3488E/MAX3490E/MAX3491E: +3.3V Powered, ±15kV ESD-Protected, 12Mbps, Slew-Rate-Limited,True RS-485/RS-422 TransceiversMAX481/MAX483/MAX485/MAX487–MAX491/MAX1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers______________________________________________________________Selection Table19-0122; Rev 8; 10/03Ordering Information appears at end of data sheet.M A X 481/M A X 483/M A X 485/M A X 487–M A X 491/M A X 1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers 2_______________________________________________________________________________________ABSOLUTE MAXIMUM RATINGSSupply Voltage (V CC ).............................................................12V Control Input Voltage (RE , DE)...................-0.5V to (V CC + 0.5V)Driver Input Voltage (DI).............................-0.5V to (V CC + 0.5V)Driver Output Voltage (A, B)...................................-8V to +12.5V Receiver Input Voltage (A, B).................................-8V to +12.5V Receiver Output Voltage (RO).....................-0.5V to (V CC +0.5V)Continuous Power Dissipation (T A = +70°C)8-Pin Plastic DIP (derate 9.09mW/°C above +70°C)....727mW 14-Pin Plastic DIP (derate 10.00mW/°C above +70°C)..800mW 8-Pin SO (derate 5.88mW/°C above +70°C).................471mW14-Pin SO (derate 8.33mW/°C above +70°C)...............667mW 8-Pin µMAX (derate 4.1mW/°C above +70°C)..............830mW 8-Pin CERDIP (derate 8.00mW/°C above +70°C).........640mW 14-Pin CERDIP (derate 9.09mW/°C above +70°C).......727mW Operating Temperature RangesMAX4_ _C_ _/MAX1487C_ A...............................0°C to +70°C MAX4__E_ _/MAX1487E_ A.............................-40°C to +85°C MAX4__MJ_/MAX1487MJA...........................-55°C to +125°C Storage Temperature Range.............................-65°C to +160°C Lead Temperature (soldering, 10sec).............................+300°CDC ELECTRICAL CHARACTERISTICS(V CC = 5V ±5%, T A = T MIN to T MAX , unless otherwise noted.) (Notes 1, 2)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.VV IN = -7VV IN = 12V V IN = -7V V IN = 12V Input Current (A, B)I IN2V TH k Ω48-7V ≤V CM ≤12V, MAX487/MAX1487R INReceiver Input Resistance -7V ≤V CM ≤12V, all devices except MAX487/MAX1487R = 27Ω(RS-485), Figure 40.4V ≤V O ≤2.4VR = 50Ω(RS-422)I O = 4mA, V ID = -200mV I O = -4mA, V ID = 200mV V CM = 0V-7V ≤V CM ≤12V DE, DI, RE DE, DI, RE MAX487/MAX1487,DE = 0V, V CC = 0V or 5.25VDE, DI, RE R = 27Ωor 50Ω, Figure 4R = 27Ωor 50Ω, Figure 4R = 27Ωor 50Ω, Figure 4DE = 0V;V CC = 0V or 5.25V,all devices except MAX487/MAX1487CONDITIONSk Ω12µA ±1I OZRThree-State (high impedance)Output Current at ReceiverV 0.4V OL Receiver Output Low Voltage 3.5V OH Receiver Output High Voltage mV 70∆V TH Receiver Input Hysteresis V -0.20.2Receiver Differential Threshold Voltage-0.2mA 0.25mA-0.81.01.55V OD2Differential Driver Output (with load)V 2V 5V OD1Differential Driver Output (no load)µA±2I IN1Input CurrentV 0.8V IL Input Low Voltage V 2.0V IH Input High Voltage V 0.2∆V OD Change in Magnitude of Driver Common-Mode Output Voltage for Complementary Output States V 0.2∆V OD Change in Magnitude of Driver Differential Output Voltage for Complementary Output States V 3V OC Driver Common-Mode Output VoltageUNITS MINTYPMAX SYMBOL PARAMETERMAX481/MAX483/MAX485/MAX487–MAX491/MAX1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers_______________________________________________________________________________________3SWITCHING CHARACTERISTICS—MAX481/MAX485, MAX490/MAX491, MAX1487(V CC = 5V ±5%, T A = T MIN to T MAX , unless otherwise noted.) (Notes 1, 2)DC ELECTRICAL CHARACTERISTICS (continued)(V CC = 5V ±5%, T A = T MIN to T MAX , unless otherwise noted.) (Notes 1, 2)ns 103060t PHLDriver Rise or Fall Time Figures 6 and 8, R DIFF = 54Ω, C L1= C L2= 100pF ns MAX490M, MAX491M MAX490C/E, MAX491C/E2090150MAX481, MAX485, MAX1487MAX490M, MAX491MMAX490C/E, MAX491C/E MAX481, MAX485, MAX1487Figures 6 and 8, R DIFF = 54Ω,C L1= C L2= 100pF MAX481 (Note 5)Figures 5 and 11, C RL = 15pF, S2 closedFigures 5 and 11, C RL = 15pF, S1 closed Figures 5 and 11, C RL = 15pF, S2 closed Figures 5 and 11, C RL = 15pF, S1 closed Figures 6 and 10, R DIFF = 54Ω,C L1= C L2= 100pFFigures 6 and 8,R DIFF = 54Ω,C L1= C L2= 100pF Figures 6 and 10,R DIFF = 54Ω,C L1= C L2= 100pF CONDITIONS ns 510t SKEW ns50200600t SHDNTime to ShutdownMbps 2.5f MAX Maximum Data Rate ns 2050t HZ Receiver Disable Time from High ns 103060t PLH 2050t LZ Receiver Disable Time from Low ns 2050t ZH Driver Input to Output Receiver Enable to Output High ns 2050t ZL Receiver Enable to Output Low 2090200ns ns 134070t HZ t SKD Driver Disable Time from High |t PLH - t PHL |DifferentialReceiver Skewns 4070t LZ Driver Disable Time from Low ns 4070t ZL Driver Enable to Output Low 31540ns51525ns 31540t R , t F 2090200Driver Output Skew to Output t PLH , t PHL Receiver Input to Output4070t ZH Driver Enable to Output High UNITS MIN TYP MAX SYMBOL PARAMETERFigures 7 and 9, C L = 100pF, S2 closed Figures 7 and 9, C L = 100pF, S1 closed Figures 7 and 9, C L = 15pF, S1 closed Figures 7 and 9, C L = 15pF, S2 closedM A X 481/M A X 483/M A X 485/M A X 487–M A X 491/M A X 1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers 4_______________________________________________________________________________________SWITCHING CHARACTERISTICS—MAX483, MAX487/MAX488/MAX489(V CC = 5V ±5%, T A = T MIN to T MAX , unless otherwise noted.) (Notes 1, 2)SWITCHING CHARACTERISTICS—MAX481/MAX485, MAX490/MAX491, MAX1487 (continued)(V CC = 5V ±5%, T A = T MIN to T MAX , unless otherwise noted.) (Notes 1, 2)3001000Figures 7 and 9, C L = 100pF, S2 closed Figures 7 and 9, C L = 100pF, S1 closed Figures 5 and 11, C L = 15pF, S2 closed,A - B = 2VCONDITIONSns 40100t ZH(SHDN)Driver Enable from Shutdown toOutput High (MAX481)nsFigures 5 and 11, C L = 15pF, S1 closed,B - A = 2Vt ZL(SHDN)Receiver Enable from Shutdownto Output Low (MAX481)ns 40100t ZL(SHDN)Driver Enable from Shutdown toOutput Low (MAX481)ns 3001000t ZH(SHDN)Receiver Enable from Shutdownto Output High (MAX481)UNITS MINTYP MAX SYMBOLPARAMETERtPLH t SKEW Figures 6 and 8, R DIFF = 54Ω,C L1= C L2= 100pFt PHL Figures 6 and 8, R DIFF = 54Ω,C L1= C L2= 100pFDriver Input to Output Driver Output Skew to Output ns 100800ns ns 2000MAX483/MAX487, Figures 7 and 9,C L = 100pF, S2 closedt ZH(SHDN)Driver Enable from Shutdown to Output High2502000ns2500MAX483/MAX487, Figures 5 and 11,C L = 15pF, S1 closedt ZL(SHDN)Receiver Enable from Shutdown to Output Lowns 2500MAX483/MAX487, Figures 5 and 11,C L = 15pF, S2 closedt ZH(SHDN)Receiver Enable from Shutdown to Output Highns 2000MAX483/MAX487, Figures 7 and 9,C L = 100pF, S1 closedt ZL(SHDN)Driver Enable from Shutdown to Output Lowns 50200600MAX483/MAX487 (Note 5) t SHDN Time to Shutdownt PHL t PLH , t PHL < 50% of data period Figures 5 and 11, C RL = 15pF, S2 closed Figures 5 and 11, C RL = 15pF, S1 closed Figures 5 and 11, C RL = 15pF, S2 closed Figures 5 and 11, C RL = 15pF, S1 closed Figures 7 and 9, C L = 15pF, S2 closed Figures 6 and 10, R DIFF = 54Ω,C L1= C L2= 100pFFigures 7 and 9, C L = 15pF, S1 closed Figures 7 and 9, C L = 100pF, S1 closed Figures 7 and 9, C L = 100pF, S2 closed CONDITIONSkbps 250f MAX 2508002000Maximum Data Rate ns 2050t HZ Receiver Disable Time from High ns 25080020002050t LZ Receiver Disable Time from Low ns 2050t ZH Receiver Enable to Output High ns 2050t ZL Receiver Enable to Output Low ns ns 1003003000t HZ t SKD Driver Disable Time from High I t PLH - t PHL I DifferentialReceiver SkewFigures 6 and 10, R DIFF = 54Ω,C L1= C L2= 100pFns 3003000t LZ Driver Disable Time from Low ns 2502000t ZL Driver Enable to Output Low ns Figures 6 and 8, R DIFF = 54Ω,C L1= C L2= 100pFns 2502000t R , t F 2502000Driver Rise or Fall Time ns t PLH Receiver Input to Output2502000t ZH Driver Enable to Output High UNITS MIN TYP MAX SYMBOL PARAMETERMAX481/MAX483/MAX485/MAX487–MAX491/MAX1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers_______________________________________________________________________________________530002.5OUTPUT CURRENT vs.RECEIVER OUTPUT LOW VOLTAGE525M A X 481-01OUTPUT LOW VOLTAGE (V)O U T P U T C U R R E N T (m A )1.515100.51.02.0203540450.90.1-50-252575RECEIVER OUTPUT LOW VOLTAGE vs.TEMPERATURE0.30.7TEMPERATURE (°C)O U T P U TL O W V O L T A G E (V )500.50.80.20.60.40100125-20-41.5 2.0 3.0 5.0OUTPUT CURRENT vs.RECEIVER OUTPUT HIGH VOLTAGE-8-16M A X 481-02OUTPUT HIGH VOLTAGE (V)O U T P U T C U R R E N T (m A )2.5 4.0-12-18-6-14-10-203.54.5 4.83.2-50-252575RECEIVER OUTPUT HIGH VOLTAGE vs.TEMPERATURE3.64.4TEMPERATURE (°C)O U T P UT H I G H V O L T A G E (V )0504.04.63.44.23.83.01001259000 1.0 3.0 4.5DRIVER OUTPUT CURRENT vs.DIFFERENTIAL OUTPUT VOLTAGE1070M A X 481-05DIFFERENTIAL OUTPUT VOLTAGE (V)O U T P U T C U R R E N T (m A )2.0 4.05030806040200.5 1.5 2.53.5 2.31.5-50-2525125DRIVER DIFFERENTIAL OUTPUT VOLTAGEvs. TEMPERATURE1.72.1TEMPERATURE (°C)D I F FE R E N T I A L O U T P U TV O L T A G E (V )751.92.21.62.01.8100502.4__________________________________________Typical Operating Characteristics(V CC = 5V, T A = +25°C, unless otherwise noted.)NOTES FOR ELECTRICAL/SWITCHING CHARACTERISTICSNote 1:All currents into device pins are positive; all currents out of device pins are negative. All voltages are referenced to deviceground unless otherwise specified.Note 2:All typical specifications are given for V CC = 5V and T A = +25°C.Note 3:Supply current specification is valid for loaded transmitters when DE = 0V.Note 4:Applies to peak current. See Typical Operating Characteristics.Note 5:The MAX481/MAX483/MAX487 are put into shutdown by bringing RE high and DE low. If the inputs are in this state for lessthan 50ns, the parts are guaranteed not to enter shutdown. If the inputs are in this state for at least 600ns, the parts are guaranteed to have entered shutdown. See Low-Power Shutdown Mode section.M A X 481/M A X 483/M A X 485/M A X 487–M A X 491/M A X 1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers 6___________________________________________________________________________________________________________________Typical Operating Characteristics (continued)(V CC = 5V, T A = +25°C, unless otherwise noted.)120008OUTPUT CURRENT vs.DRIVER OUTPUT LOW VOLTAGE20100M A X 481-07OUTPUT LOW VOLTAGE (V)O U T P U T C U R R E N T (m A )6604024801012140-1200-7-5-15OUTPUT CURRENT vs.DRIVER OUTPUT HIGH VOLTAGE-20-80M A X 481-08OUTPUT HIGH VOLTAGE (V)O U T P U T C U R R E N T (m A )-31-603-6-4-2024-100-40100-40-60-2040100120MAX1487SUPPLY CURRENT vs. TEMPERATURE300TEMPERATURE (°C)S U P P L Y C U R R E N T (µA )20608050020060040000140100-50-2550100MAX481/MAX485/MAX490/MAX491SUPPLY CURRENT vs. TEMPERATURE300TEMPERATURE (°C)S U P P L Y C U R R E N T (µA )257550020060040000125100-50-2550100MAX483/MAX487–MAX489SUPPLY CURRENT vs. TEMPERATURE300TEMPERATURE (°C)S U P P L Y C U R R E N T (µA )257550020060040000125MAX481/MAX483/MAX485/MAX487–MAX491/MAX1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers_______________________________________________________________________________________7______________________________________________________________Pin DescriptionFigure 1. MAX481/MAX483/MAX485/MAX487/MAX1487 Pin Configuration and Typical Operating CircuitM A X 481/M A X 483/M A X 485/M A X 487–M A X 491/M A X 1487__________Applications InformationThe MAX481/MAX483/MAX485/MAX487–MAX491 and MAX1487 are low-power transceivers for RS-485 and RS-422 communications. The MAX481, MAX485, MAX490,MAX491, and MAX1487 can transmit and receive at data rates up to 2.5Mbps, while the MAX483, MAX487,MAX488, and MAX489 are specified for data rates up to 250kbps. The MAX488–MAX491 are full-duplex trans-ceivers while the MAX481, MAX483, MAX485, MAX487,and MAX1487 are half-duplex. In addition, Driver Enable (DE) and Receiver Enable (RE) pins are included on the MAX481, MAX483, MAX485, MAX487, MAX489,MAX491, and MAX1487. When disabled, the driver and receiver outputs are high impedance.MAX487/MAX1487:128 Transceivers on the BusThe 48k Ω, 1/4-unit-load receiver input impedance of the MAX487 and MAX1487 allows up to 128 transceivers on a bus, compared to the 1-unit load (12k Ωinput impedance) of standard RS-485 drivers (32 trans-ceivers maximum). Any combination of MAX487/MAX1487 and other RS-485 transceivers with a total of 32 unit loads or less can be put on the bus. The MAX481/MAX483/MAX485 and MAX488–MAX491 have standard 12k ΩReceiver Input impedance.Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers 8_______________________________________________________________________________________Figure 2. MAX488/MAX490 Pin Configuration and Typical Operating CircuitFigure 3. MAX489/MAX491 Pin Configuration and Typical Operating CircuitMAX483/MAX487/MAX488/MAX489:Reduced EMI and ReflectionsThe MAX483 and MAX487–MAX489 are slew-rate limit-ed, minimizing EMI and reducing reflections caused by improperly terminated cables. Figure 12 shows the dri-ver output waveform and its Fourier analysis of a 150kHz signal transmitted by a MAX481, MAX485,MAX490, MAX491, or MAX1487. High-frequency har-monics with large amplitudes are evident. Figure 13shows the same information displayed for a MAX483,MAX487, MAX488, or MAX489 transmitting under the same conditions. Figure 13’s high-frequency harmonics have much lower amplitudes, and the potential for EMI is significantly reduced.MAX481/MAX483/MAX485/MAX487–MAX491/MAX1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers_______________________________________________________________________________________9_________________________________________________________________Test CircuitsFigure 4. Driver DC Test Load Figure 5. Receiver Timing Test LoadFigure 6. Driver/Receiver Timing Test Circuit Figure 7. Driver Timing Test LoadM A X 481/M A X 483/M A X 485/M A X 487–M A X 491/M A X 1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers 10_______________________________________________________Switching Waveforms_________________Function Tables (MAX481/MAX483/MAX485/MAX487/MAX1487)Figure 8. Driver Propagation DelaysFigure 9. Driver Enable and Disable Times (except MAX488 and MAX490)Figure 10. Receiver Propagation DelaysFigure 11. Receiver Enable and Disable Times (except MAX488and MAX490)Table 1. TransmittingTable 2. ReceivingLow-Power Shutdown Mode (MAX481/MAX483/MAX487)A low-power shutdown mode is initiated by bringing both RE high and DE low. The devices will not shut down unless both the driver and receiver are disabled.In shutdown, the devices typically draw only 0.1µA of supply current.RE and DE may be driven simultaneously; the parts 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 600ns, the parts are guaranteed to entershutdown.For the MAX481, MAX483, and MAX487, the t ZH and t ZL enable times assume the part was not in the low-power shutdown state (the MAX485/MAX488–MAX491and MAX1487 can not be shut down). The tZH(SHDN)and t ZL(SHDN)enable times assume the parts were shut down (see Electrical Characteristics ).It takes the drivers and receivers longer to become enabled from the low-power shutdown state(t ZH(SHDN ), t ZL(SHDN)) than from the operating mode(t ZH , t ZL ). (The parts are in operating mode if the –R —E –,DE inputs equal a logical 0,1 or 1,1 or 0, 0.)Driver Output Protection Excessive output current and power dissipation causedby faults or by bus contention are prevented by two mechanisms. A foldback current limit on the output stage provides immediate protection against short cir-cuits over the whole common-mode voltage range (see Typical Operating Characteristics ). In addition, a ther-mal shutdown circuit forces the driver outputs into a high-impedance state if the die temperature rises excessively.Propagation DelayMany digital encoding schemes depend on the differ-ence between the driver and receiver propagation delay times. Typical propagation delays are shown in Figures 15–18 using Figure 14’s test circuit.The difference in receiver delay times, | t PLH - t PHL |, istypically under 13ns for the MAX481, MAX485,MAX490, MAX491, and MAX1487 and is typically lessthan 100ns for the MAX483 and MAX487–MAX489.The driver skew times are typically 5ns (10ns max) for the MAX481, MAX485, MAX490, MAX491, and MAX1487, and are typically 100ns (800ns max) for theMAX483 and MAX487–MAX489.MAX481/MAX483/MAX485/MAX487–MAX491/MAX1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers______________________________________________________________________________________1110dB/div0Hz 5MHz 500kHz/div 10dB/div0Hz 5MHz500kHz/divFigure 12. Driver Output Waveform and FFT Plot of MAX481/MAX485/MAX490/MAX491/MAX1487 Transmitting a 150kHzSignalFigure 13. Driver Output Waveform and FFT Plot of MAX483/MAX487–MAX489 Transmitting a 150kHz SignalM A X 481/M A X 483/M A X 485/M A X 487–M A X 491/M A X 1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers12______________________________________________________________________________________V CC = 5V T A = +25°C V CC = 5V T A = +25°C V CC = 5V T A = +25°CV CC = 5V T A = +25°C Figure 14. Receiver Propagation Delay Test Circuit Figure 15. MAX481/MAX485/MAX490/MAX491/MAX1487Receiver t PHL Figure 16. MAX481/MAX485/MAX490/MAX491/MAX1487Receiver t PLH PHL Figure 18. MAX483, MAX487–MAX489 Receiver t PLHLine Length vs. Data Rate The RS-485/RS-422 standard covers line lengths up to 4000 feet. For line lengths greater than 4000 feet, see Figure 23.Figures 19 and 20 show the system differential voltage for the parts driving 4000 feet of 26AWG twisted-pair wire at 110kHz into 120Ωloads.Typical Applications The MAX481, MAX483, MAX485, MAX487–MAX491, and MAX1487 transceivers are designed for bidirectional datacommunications on multipoint bus transmission lines.Figures 21 and 22 show typical network applications circuits. These parts can also be used as line repeaters, with cable lengths longer than 4000 feet, as shown in Figure 23.To minimize reflections, the line should be terminated at both ends in its characteristic impedance, and stub lengths off the main line should be kept as short as possi-ble. The slew-rate-limited MAX483 and MAX487–MAX489are more tolerant of imperfect termination.MAX481/MAX483/MAX485/MAX487–MAX491/MAX1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers______________________________________________________________________________________13DI V Y -V Z RO 5V 0V 1V 0V -1V 5V 0V 2µs/divFigure 19. MAX481/MAX485/MAX490/MAX491/MAX1487 System Differential Voltage at 110kHz Driving 4000ft of Cable Figure 20. MAX483, MAX487–MAX489 System Differential Voltage at 110kHz Driving 4000ft of CableFigure 21. MAX481/MAX483/MAX485/MAX487/MAX1487 Typical Half-Duplex RS-485 NetworkM A X 481/M A X 483/M A X 485/M A X 487–M A X 491/M A X 1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers14______________________________________________________________________________________Figure 22. MAX488–MAX491 Full-Duplex RS-485 NetworkFigure 23. Line Repeater for MAX488–MAX491Isolated RS-485For isolated RS-485 applications, see the MAX253 and MAX1480 data sheets.MAX481/MAX483/MAX485/MAX487–MAX491/MAX1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers______________________________________________________________________________________15_______________Ordering Information _________________Chip Topographies MAX481/MAX483/MAX485/MAX487/MAX1487N.C. RO 0.054"(1.372mm)0.080"(2.032mm)DE DI GNDB N.C.VCCA RE * Contact factory for dice specifications.__Ordering Information (continued)M A X 481/M A X 483/M A X 485/M A X 487–M A X 491/M A X 1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers16______________________________________________________________________________________TRANSISTOR COUNT: 248SUBSTRATE CONNECTED TO GNDMAX488/MAX490B RO 0.054"(1.372mm)0.080"(2.032mm) N.C. DI GND Z A V CC Y N.C._____________________________________________Chip Topographies (continued)MAX489/MAX491B RO 0.054"(1.372mm)0.080"(2.032mm) DE DI GND Z A V CC Y REMAX481/MAX483/MAX485/MAX487–MAX491/MAX1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers______________________________________________________________________________________17Package 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 .)SO IC N.E PSM A X 481/M A X 483/M A X 485/M A X 487–M A X 491/M A X 1487Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers18______________________________________________________________________________________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 .)MAX481/MAX483/MAX485/MAX487–MAX491Low-Power, Slew-Rate-Limited RS-485/RS-422 TransceiversMaxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses areimplied. 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 ____________________19©2003 Maxim Integrated Products Printed USAis a registered trademark of Maxim Integrated Products.M A X 481/M A X 483/M A X 485/M A X 487–M A X 491/M A X 1487PD I P N.E PS 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.)。
工业级千兆以太网光电转换器 IMC-101G系列 说明书
Services PressureTemperatureLiquid AnalysisRegistrationSystemComponentsSolutionsTI 381C/28/zh/v 1.0Liquiline M CM42p H/ORP /电导率/浓度/电阻系数/数字探头两线制变送器用于防爆和非防爆场所。
应用L i qui l ine M C M42是一种能应用于任何过程控制领域的模块化的两线制变送器。
根据订货不同,L i q ui l in e 有一路或两路电流输出,或者按照F F 总线（FOU N DAT IO N Fi e ld b us ）,P R OFI B US-PA 及H a rt 协议直接与现场总线相连。
L i qui l ine 是依据国际安全标准IE C 61508开发出来的。
外壳,有耐腐蚀的塑料型,和卫生的不锈钢型供选择，应用于以下领域：·化工过程制药工业食品技术防爆应用极其坚固···优点··—Me mo se n s 智能电极型可动态显示电缆连接中断红色报警灯能立刻报告错误。
有用户引导设定，图形显示和简单的文本引导。
SI L 2，AT E X ，F M ，CSA ，N E PS I ，TI IS ，IP 67，NE M A 4X—设定与标定配有密码保护—能与所有型号的p H 探头（玻璃，I S FE T ，数字探头）和电导率探头进行连接·工业解决方案：模块化概念：探头可随意现场更换、互换资产管理(F ie ld ca r e,W @M )节省开支:操作设定简单(多功能键)由于M em os e ns 智能电极技术的出现,无需在场进行标定维护系统可以预见到什么时候探头需要清洗,标定，更换。
由于模块化设计减少了存储安全性：基本特征特殊特征测量系统输入输出接线性能特性安装环境模块化设计快速设定飞梭键和简明文本探头监测过程检查系统(PCS )软件包安全性p H ／O RP 电导率数字探头p H /ORP 电导率数字探头输出信号报警信号负载输出信号范围安装接地供电和信号回路探头连接:p H /O R P 探头连接:电导率探头连接:数字探头p H /ORP 电导率数字探头安装板防雨罩防爆区域的安装环境温度范围环境温度界限存储温度电磁兼容性入口保护相对湿度防爆规范4/20mA 电流输出防爆规范P RO F IB U S P A 和FF 现场总线重量材料人机界面定货信息证书和认证附件操作组成产品结构交货范围CE 认证防爆认证pH /O RP 电导率数字探头(附加的)操作手册C 42文档M 21212122191919203333334455556789710101010101010102222222222222224252624252323272930272626263131111111141718基本特征模块化设计内置Liqu ilin e（带有探头模块，无连接线）快速设定飞梭键和简明文本在一分钟内得到第一个测量值在快速设定菜单中设定完几个参数后,测量点已经准备好测量.你可以确认已经完成重要的设定。
MAX471电流检测
网站：/dm/elec/.pdf-MAX471／MAX472 是美国MAXIM 公司生产的双向、精密电流传感放大器。
MAX471 内置35mΩ精密传感电阻,可测量电流的上下限为±3A。
对于允许较大电流的场合,则可选用MAX472。
在这种情况下,用户可根据自己的需要配置外接的传感电阻与增益电阻。
MAX471／MAX472 都可通过一个输出电阻将电流输出转化为对地电压输出。
MAX471／MAX472 所需的供电电压VBR／VCC 为3～36V,所能跟踪的电流的变化频率可达到130kHz。
二者均采用8 脚封装. MAX471／MAX472 可广泛应用于电流供电系统、便携式设备、监控系统及能源管理系统等。
１引脚说明MAX471 引脚图如图１所示,MAX472 引脚图如图２所示。
各引脚功能说明如下：SHDN 为关闭信号,正常操作时接地;当它为高电平时,供电电流小于5μA。
RS+为内传感电阻的电源端。
N.C．表示无内部连接。
RG1 为增益电阻的连接端,增益电阻RG1 连接到传感电阻的电源端。
GND 为地端或电源负端。
SIGN 为集电极开路逻辑输出。
对于MAX471,SIGN 为低电平表示电流由RS-流向RS+;对于MAX472,SIGN为低电平表示Vsense（传感电阻两端的电压）为负。
当SIGN 为高电平时,SIGN 呈阻状态。
RS-为内传感电阻的负载端。
RG２为增益电阻的连接端,增益电阻RG２连接到传感电阻的负载端。
Vcc 为MAX472 的正电源连接端。
连接传感电阻与增益电阻。
OUT 为电流输出端,该电流的大小正比于流过传感电阻的电流。
２工作原理MAX471 的功能框图如图3 所示, MAX472 的功能框图如图4 所示。
MAX471和MAX472电流传感放大器的独特布局大大简化了电流监控的设计。
MAX471／MAX472 包含两个放大器,如图３和图４所示。
传感电流Isense通过传感电阻Rsense从RS+流向RS-（反之亦然）。
MAX471在电流监测中的应用
MAX471在电流监测中的应⽤器件应⽤MAX471在电流监测中的应⽤上海航天测控通信研究所(上海200086) 林晓莉摘 要 测量电流专⽤的运算放⼤器M AX471与极少的外部元件连接,可构成⼀个⾼精度、线性度好、使⽤⽅便、适⽤范围⼴的电流监测电路。
⽂中介绍了MAX471的原理及其在电流监测中的应⽤。
关键词 差分放⼤ 电流取样电阻 满量程1 概述在电流测量技术中,为了减少测量电路对被测电流的影响,通常采⽤在被测电路中串联⼀只⼩阻值的取样电阻进⾏I-V转换,再经过差分放⼤电路实现⼩电压放⼤的⽅法。
测量精度要求越⾼,线路就越复杂。
MAX471是美国Maxim公司向市场推出的⼀种新型的、⾼精度的电流检测放⼤器。
它可应⽤于笔记本电脑、⼿机、母⼦电话机、便携式测量仪、能源管理系统等中的电流监测单元。
M AX471内部有⼀个35mΨ的电流采样电阻,可以测量±3A 的电流。
MAX471有⼀个电流输出端,只需外接⼀个电阻,将电流转换成对地电压,就可组成⾼精度的电流监测电路。
它的⼯作电压和被测电路电流范围宽,因此得到⼴泛的应⽤。
2 MAX471的特点和结构2.1 主要特点M AX471有下列主要特点:(1)真正的⾼端电流取样;(2)精密的内置取样电阻(35mΨ);(3)电流转换⽐(I OU T/I LOAD)为500µA/A;(4)在规定⼯作温度下测量精度可达2%;(5)可监视电池的充放电;(6)最⼤的测量电流为3A;(7)最⼤耗电电流为113µA;(8)休眠时最⼤耗电电流为18µA;(9)⼯作电压为3～36V;(10)8脚的双列直插或SO封装形式。
2.2 引脚功能及内部结构M AX471的引脚排列及其引脚功能分别见图1和表1所⽰。
图1 MA X471的引脚排列图表1 MAX471引脚功能表脚号符号功能1SHDN休眠端。
接地时处于⼯作状态。
接⾼电平时,休眠状态,耗电电流⼩于18µA。
CSA 认证证书 - Siemens AG 电子产品及研发团队1的产品说明书
Types(Note 6) 3RT2015, 3RT2315: Max 7 FLA / 51 LRA, 600Vac
Voltage
1-phase
3-phase
110-120 Vac 1/4hp, 5.8 FLA/ -
-
200 Vac
1/2hp, 5.6 FLA/ -
1-1/2hp, 6.9 FLA / 46 LRA
Type 3RT2315: 16 A, 600 V, AC resistance Type 3RT2316: 18 A, 600 V, AC resistance Type 3RT2317: 20 A, 600 V, AC resistance
Type 3RT201: 20 A, 600 V, AC Electric heating (250 000 c.) Type(Note 7) LEN00B00....B:
440/480 Vac -
NO: 7-1/2, 11 / 63.5; NC: 5, 7.6 / 46
DQD 507 Rev. 2019-04-30
© 2018 CSA Group. All rights reserved.
Page 2
Certificate: 2227270 Project: 80066349
208 Vac
1-1/2hp, 11.0 FLA/ 66.0 LRA 3hp, 10.6 FLA/ 71.0 LRA
208 Vac
1/2hp, 5.4 FLA/ -
1-1/2hp, 6.6 FLA / 44 LRA
220/240 Vac 3/4hp, 6.9 FLA/ -
2hp, 6.8 FLA / 50 LRA
380-415 Vac -
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Not Recommended for New DesignsThis product was manufactured for Maxim by an outside wafer foundry using a process that is no longer available. It is not recommended for new designs. The data sheet remains available for existing users.A Maxim replacement or an industry second-source may be available. Please see the QuickView data sheet for this part or contact technical support for assistance.For further information, contact Maxim’s Applications Tech Support._______________General DescriptionThe MAX471/MAX472 are complete, bidirectional, high-side current-sense amplifiers for portable PCs, tele-phones, and other systems where battery/DC power-line monitoring is critical. High-side power-line monitoring is especially useful in battery-powered sys-tems, since it does not interfere with the ground paths of the battery chargers or monitors often found in “smart” batteries.The MAX471 has an internal 35m Ωcurrent-sense resis-tor and measures battery currents up to ±3A. For appli-cations requiring higher current or increased flexibility,the MAX472 functions with external sense and gain-set-ting resistors. Both devices have a current output that can be converted to a ground-referred voltage with a single resistor, allowing a wide range of battery volt-ages and currents.An open-collector SIGN output indicates current-flow direction, so the user can monitor whether a battery is being charged or discharged. Both devices operate from 3V to 36V, draw less than 100µA over tempera-ture, and include a 18µA max shutdown mode.________________________ApplicationsPortable PCs:Notebooks/Subnotebooks/Palmtops Smart Battery Packs Cellular Phones Portable PhonesPortable Test/Measurement Systems Battery-Operated Systems Energy Management Systems____________________________Featureso Complete High-Side Current Sensing o Precision Internal Sense Resistor (MAX471)o 2% Accuracy Over Temperature o Monitors Both Charge and Dischargeo 3A Sense Capability with Internal Sense Resistor (MAX471)o Higher Current-Sense Capability with External Sense Resistor (MAX472)o 100µA Max Supply Current o 18µA Max Shutdown Mode o 3V to 36V Supply Operation o 8-Pin DIP/SO Packages______________Ordering InformationMAX471/MAX472Precision, High-Side Current-Sense Amplifiers________________________________________________________________Maxim Integrated Products1_________________Pin Configurations__________Typical Operating Circuit19-0335; Rev 2; 12/96For free samples & the latest literature: , or phone 1-800-998-8800M A X 471/M A X 472Precision, High-SideCurrent-Sense AmplifiersABSOLUTE MAXIMUM RATINGSELECTRICAL CHARACTERISTICS—MAX471(RS+ = +3V to +36V, T A = T MIN to T MAX , 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.Supply Voltage, RS+, RS-, V CC to GND....................-0.3V, +40V RMS Current, RS+ to RS- (MAX471 only)..........................±3.3A Peak Current, (RS+ to RS-)......................................see Figure 5Differential Input Voltage, RG1 to RG2 (MAX472 only) .....±0.3V Voltage at Any Pin Except SIGNMAX471 only...........................................-0.3V to (RS+ - 0.3V)MAX472 only..........................................-0.3V to (V CC + 0.3V)Voltage at SIGN......................................................-0.3V to +40V Current into SHDN, GND, OUT, RG1, RG2, V CC ................±50mA Current into SIGN.................................................+10mA, -50mAContinuous Power Dissipation (T A = +70°C)MAX471 (Note 1):Plastic DIP (derate 17.5mW/°C above +70°C)..................1.4W SO (derate 9.9mW/°C above +70°C).............................791mW MAX472 :Plastic DIP (derate 9.09mW/°C above +70°C)..............727mW SO (derate 5.88mW/°C above +70°C)...........................471mW Operating Temperature RangesMAX47_C_A........................................................0°C to +70°C MAX47_E_A.....................................................-40°C to +85°C Junction Temperature Range............................-60°C to +150°C Storage Temperature Range.............................-60°C to +160°C Lead Temperature (soldering, 10sec).............................+300°CNote 1:Due to special packaging considerations, MAX471 (DIP, SO) has a higher power dissipation rating than the MAX472. RS+and RS- must be soldered to large copper traces to achieve this dissipation rating.MAX471/MAX472Precision, High-Side Current-Sense Amplifiers_______________________________________________________________________________________3ELECTRICAL CHARACTERISTICS—MAX472(V CC = +3V to +36V, RG1 = RG2 = 200Ω, T A = T MIN to T MAX , unless otherwise noted. Typical values are at T A = +25°C.)Note 2:V OS is defined as the input voltage (V SENSE ) required to give minimum I OUT .Note 3:V SENSE is the voltage across the sense resistor.M A X 471/M A X 472Precision, High-SideCurrent-Sense Amplifiers 4_________________________________________________________________________________________________________________________________Typical Operating Characteristics(Typical Operating Circuit (MAX471) or circuit of Figure 4, RG1 = RG2 = 200Ω, R OUT = 2k Ω(MAX472), T A = +25°C, unless otherwise noted.)6535SUPPLY CURRENT vs. SUPPLY VOLTAGE40V RS+ (V)S U P P L Y C U R R E N T (µA )212415189123627303336455055602.500.52.0I S H D N (µA )1.51.0SHUTDOWN CURRENT vs. SUPPLY VOLTAGEV RS+(V)2124151891236273033364-2SIGN THRESHOLD vs. SUPPLY VOLTAGE-1S I G N T H R E S H O L D (m A )2124151891236273033360123V RS+ (V)0.6O F F S E T C U R R E N T (µA )MAX471NO-LOAD OFFSET CURRENT vs.SUPPLY VOLTAGEV RS+ (V)2124151891236273033360.81.01.21.41.61.82.02.22.428-4080TEMPERATURE (°C)R E S I S T A N C E (m Ω)2030-206040M A X 1471-07MAX471RS+ TO RS- RESISTANCE vs.TEMPERATURE3234363840-120.010.10MAX471ERROR vs. LOAD CURRENTI LOAD (A)E R R O R (%)110-15-6-9-303691215400.01101000MAX471POWER-SUPPLY REJECTION RATIOvs. FREQUENCYPOWER-SUPPLY FREQUENCY (kHz)P S R R (%)1100353025201510500.103.00MAX472NO-LOAD OUTPUT ERROR vs.SUPPLY VOLTAGE0.5V CC (V)IO U T (µA )2124151891236273033361.01.52.02.50.70E R R O R (%)MAX472ERROR vs. SUPPLY VOLTAGEV CC (V)2124151891236273033360.800.901.001.10MAX471/MAX472Precision, High-Side Current-Sense Amplifiers_______________________________________________________________________________________525-250.1101000MAX472ERROR vs. SENSE VOLTAGEV SENSE (mV)E R R O R (%)1550-5-1511001mA10mA100mA1A0.100.20.30.40.5MAX471 NOISE vs. LOAD C URRENTI SENSEI O U T N O I S E (µA R M S )M A X 471-15____________________________Typical Operating Characteristics (continued)(Typical Operating Circuit (MAX471) or circuit of Figure 4, RG1 = RG2 = 200Ω, R OUT = 2k Ω(MAX472), T A = +25°C, unless otherwise noted.)100µs/divV CC = 10V, R OUT = 2k Ω 1%, SIGN PULL-UP = 50k Ω 1%LOAD CURRENT 50mA/div V OUT 50mV/divMAX4710mA to 100mA TRANSIENT RESPONSE0A10µs/divI LOAD = 1A, R OUT = 2k Ω 1%V OUT500mV/div MAX471 START-UP DELAY V SHDN 5V/div10µs/divR OUT = 2k Ω 1%I LOAD 1A/divMAX4710A TO 3A TRANSIENT RESPONSEV OUT 10mV/div100µs/divV CC = 10V, R OUT = 2k Ω 1%, SIGN PULL-UP = 50k Ω 1%LOAD CURRENT 100mA/div50mA/div V OUT 50mV/divMAX471-100mA to +100mA TRANSIENT RESPONSESIGN 50mV/div0AM A X 471/M A X 472_______________Detailed DescriptionThe MAX471 and MAX472 current-sense amplifier’s unique topology allows a simple design to accurately monitor current flow. The MAX471/MAX472 contain two amplifiers operating as shown in Figures 1 and 2. The battery/load current flows from RS+ to RS- (or vice versa) through R SENSE . Current flows through either RG1 and Q1 or RG2 and Q2, depending on the sense-resistor current direction. Internal circuitry, not shown in Figures 1 and 2, prevents Q1 and Q2 from turning on at the same time. The MAX472 is identical to the MAX471, except that R SENSE and gain-setting resistors RG1 and RG2 are external (Figure 2).To analyze the circuit of Figure 1, assume that current flows from RS+ to RS- and that OUT is connected to GND through a resistor. In this case, amplifier A1 is active and output current I OUT flows from the emitter of Q1. Since no current flows through RG2 (Q2 is off), the negative input of A1 is equal to V SOURCE - (I LOAD x R SENSE ). The open-loop gain of A1 forces its positive input to essentially the same level as the negative input.Therefore, the drop across RG1 equals I LOAD x R SENSE . Then, since I OUT flows through Q1 and RG (ignoring the extremely low base currents), I OUT x RG1= I LOAD x R SENSE , or:I OUT = (I LOAD x R SENSE )/ RG1Current OutputThe output voltage equation for the MAX471/MAX472 is given below. In the MAX471, the current-gain ratio has been preset to 500µA/A so that an output resistor (R OUT ) of 2k Ωyields 1V/A for a full-scale value of +3V at ±3A. Other full-scale voltages can be set with differ-ent R OUT values, but the output voltage can be no greater than V RS+- 1.5V for the MAX471 or V RG_- 1.5V for the MAX472.V OUT = (R SENSE x R OUT x I LOAD ) / RGwhere V OUT = the desired full-scale output voltage,I LOAD = the full-scale current being sensed, R SENSE =the current-sense resistor, R OUT = the voltage-setting resistor, and RG = the gain-setting resistor (RG = RG1= RG2).The above equation can be modified to determine the R OUT required for a particular full-scale range:R OUT = (V OUT x RG) / (I LOAD x R SENSE )For the MAX471, this reduces to:R OUT = V OUT / (I LOAD x 500µA/A)OUT is a high-impedance current-source output that can be connected to other MAX471/MAX472 OUT pinsPrecision, High-SideCurrent-Sense Amplifiers 6_____________________________________________________________________________________________________________________________________________________Pin DescriptionMAX471/MAX472Precision, High-Side Current-Sense Amplifiers_______________________________________________________________________________________7Figure 1. MAX471 Functional DiagramFigure 2. MAX472 Functional DiagramM A X 471/M A X 472for current summing. A single scaling resistor is required when summing OUT currents from multiple devices (Figure 3). Current can be integrated by con-necting OUT to a capacitive load.SIGN OutputThe current at OUT indicates magnitude. The SIGN out-put indicates the current’s direction. Operation of the SIGN comparator is straightforward. When Q1 (Figures 1 and 2) conducts, the output of A1 is high while A2’s output is zero. Under this condition, a high SIGN output indicates positive current flow (from RS+ to RS-). In bat-tery-operated systems, this is useful for determining whether the battery is charging or discharging. The SIGN output may not correctly indicate if the load cur-rent is such that I OUT is less than 3.5µA. The MAX471’s SIGN output accurately indicates the direction of cur-rent flow for load currents greater than 7mA.SIGN is an open-collector output (sinks current only),allowing easy interface with logic circuits powered from any voltage. Connect a 100k Ωpull-up resistor from SIGN to the logic supply. The convention chosen for the polarity of the SIGN output ensures that it draws no current when the battery is being discharged. If current direction is not needed, float the SIGN pin.ShutdownWhen SHDN is high, the MAX471/MAX472 are shut down and consume less than 18µA. In shutdown mode,SIGN is high impedance and OUT turns off.__________Applications InformationMAX471The MAX471 obtains its power from the RS- pin. This includes MAX471 current consumption in the total sys-tem current measured by the MAX471. The small drop across R SENSE does not affect the MAX471’s perfor-mance.Resistor SelectionSince OUT delivers a current, an external voltage gain-setting resistor (R OUT to ground) is required at the OUT pin in order to get a voltage. R SENSE is internal to the MAX471. RG1 and RG2 are factory trimmed for an out-put current ratio (output current to load current) of 500µA/A. Since they are manufactured of the same material and in very close proximity on the chip, they provide a high degree of temperature stability. Choose R OUT for the desired full-scale output voltage up to RS-- 1.5V (see the Current Output section).Precision, High-SideCurrent-Sense Amplifiers 8_______________________________________________________________________________________Figure 3. Paralleling MAX471s to Sense Higher Load Current Figure 4. MAX472 Standard Application CircuitPeak Sense CurrentThe MAX471’s maximum sense current is 3A RMS . For power-up, fault conditions, or other infrequent events,MAX472R SENSE , RG1, and RG2 are externally connected on the MAX472. V CC can be connected to either the load/charge or power-source/battery side of the sense resistor. Connect V CC to the load/charge side of R SENSE if you want to include the MAX472 current drain in the measured current.Suggested Component Valuesfor Various ApplicationsThe general circuit of Figure 4 is useful in a wide variety of applications. It can be used for high-current applica-tions (greater than 3A), and also for those where the full-scale load current is less than the 3A of the MAX471.Table 1 shows suggested component values and indi-cates the resulting scale factors for various applications required to sense currents from 100mA to 10A.Higher or lower sense-current circuits can also be built.Select components and calculate circuit errors using the guidelines and formulas in the following section.R SENSEChoose R SENSE based on the following criteria:a)Voltage Loss: A high R SENSE value will cause the power-source voltage to degrade through IR loss.For least voltage loss, use the lowest R SENSE value.b)Accuracy: A high R SENSE value allows lower currents to be measured more accurately. This is because offsets become less significant when the sense voltage is larger.c)Efficiency and Power Dissipation:At high current levels, the I 2R losses in R SENSE may be significant.Take this into consideration when choosing the resistor value and power dissipation (wattage) rat-ing. Also, if the sense resistor is allowed to heat up excessively, its value may drift.d)Inductance:If there is a large high-frequency com-ponent to I SENSE , you will want to keep inductance low. Wire-wound resistors have the highest induc-tance, while metal film is somewhat better. Low-inductance metal-film resistors are available. Instead of being spiral wrapped around a core, as in metal-film or wire-wound resistors, these are a straight band of metal. They are made in values under 1Ω.e)Cost:If the cost of R SENSE becomes an issue, you may want to use an alternative solution, as shown in Figure 6. This solution uses the PC board traces to create a sense resistor. Because of the inaccuracies of the copper “resistor,” you will need to adjust the full-scale current value with a potentiometer. Also,the resistance temperature coefficient of copper is fairly high (approximately 0.4%/°C), so systems that experience a wide temperature variance should take this into account.MAX471/MAX472Precision, High-Side Current-Sense AmplifiersTable 1. Suggested Component Values for the MAX472M A X 471/M A X 472In Figure 6, assume the load current to be measured is 10A and that you have determined a 0.3 inch wide, 2ounce copper to be appropriate. The resistivity of 0.1inch wide, 2 ounce copper is 30m Ω/ft (see Note 4). For 10A you may want R SENSE = 5m Ωfor a 50mV drop at full scale. This resistor will require about 2 inches of 0.1inch wide copper trace.RG1 and RG2Once R SENSE is chosen, RG1 and RG2 can be chosen to define the current-gain ratio (R SENSE /RG). Choose RG = RG1 = RG2 based on the following criteria:a)1ΩInput Resistance.The minimum RG value is lim-ited by the 1Ωinput resistance, and also by the out-put current limitation (see below). As RG is reduced,the input resistance becomes a larger portion of the total gain-setting resistance. With RG = 50Ω, the input resistance produces a 2% difference between the expected and actual current-gain ratio. This is a gain error that does not affect linearity and can be removed by adjusting RG or R OUT .b)Efficiency.As RG is reduced, I OUT gets larger for a given load current. Power dissipated in R OUT is not going to the load, and therefore reduces overall effi-ciency. This is significant only when the sense cur-rent is small.c)Maximum Output Current Limitation.I OUT is limit-ed to 1.5mA, requiring RG ≥V SENSE / 1.5mA. For V SENSE = 60mV, RG must be ≥40Ω.d)Headroom.The MAX472 requires a minimum of 1.5V between the lower of the voltage at RG1 or RG2 (V RG_) and V OUT . As RG becomes larger, the voltage drop across RG also becomes larger for a given I OUT . This voltage drop further limits the maxi-mum full-scale V OUT . Assuming the drop across R SENSE is small and V CC is connected to either side of R SENSE , V OUT (max) = V CC - (1.5V + I OUT (max) x RG).e)Output Offset Error at Low Load rge RG values reduce I OUT for a given load current. As I OUT gets smaller, the 2.5µA max output offset-error current becomes a larger part of the overall output current. Keeping the gain high by choosing a low value for RG minimizes this offset error.f)Input Bias Current and Input Bias Current Mismatching.The size of RG also affects the errors introduced by the input bias and input bias mis-matching currents. After selecting the ratio, check tomake sure RG is small enough that I B and I OS do not add any appreciable errors. The full-scale error is given by:% Error = (RG1 - RG2) x I B + I OS x RG x 100I FS x R SENSEwhere RG1 and RG2 are the gain resistors, I B is the bias current, I OS is the bias-current mismatch, I FS is the full-scale current, and R SENSE is the sense resistor.Assuming a 5A load current, 10m ΩR SENSE , and 100ΩRG, the current-gain ratio is 100µA/A, yielding a full-scale I OUT of 500µA. Using the maximum values for I B (20µA) and I OS (2µA), and 1% resistors for RG1 and RG2 (RG1 - RG2 = 2Ω), the worst-case error at full scale calculates to:2Ωx 20µA + 100Ωx 2µA = 0.48%5m Ωx 5AThe error may be reduced by: a) better matching of RG1 and RG2, b) increasing R SENSE , or c) decreasing RG.Current-Sense Adjustment (Resistor Range, Output Adjust)Choose R OUT after selecting R SENSE , RG1, and RG2.Choose R OUT to obtain the full-scale voltage youPrecision, High-SideCurrent-Sense Amplifiers 10______________________________________________________________________________________Note 4:Printed Circuit Design, by Gerald L. Ginsberg; McGraw-Hill, Inc.; page 185.Figure 6. MAX472 Connections Showing Use of PC Board Tracerequire, given the full-scale I OUT determined by R SENSE, RG1, and RG2. The high compliance of OUT permits using R OUT values up to 10kΩwith minimal error. Values above 10kΩare not usually recommend-ed. The impedance of OUT’s load (e.g., the input of an op amp or ADC) must be much greater than R OUT (e.g., 100 x R OUT) to avoid degrading the measure-ment accuracy.High-Current Measurement The MAX472 can achieve higher current measurements than the MAX471 can. Low-value sense resistors may be paralleled to obtain even lower values, or the PC board trace may be adjusted for any value.An alternative method is to connect several MAX471s in parallel and connect the high-impedance current-source OUT pins together to indicate the total system current (Figure 3). Pay attention to layout to ensure equal IR drops in the paralleled connection. This is necessary to achieve equal current sharing.Power-Supply Bypassing and Grounding The MAX471 has been designed as a “high side” (posi-tive terminal) current monitor to ease the task of grounding any battery charger, thermistor, etc. that may be a part of the battery pack. Grounding the MAX471 requires no special precautions; follow the same cautionary steps that apply to the system as a whole. High-current systems can experience large volt-age drops across a ground plane, and this drop may add to or subtract from V OUT. For highest current-mea-surement accuracy, use a single-point “star” ground.The MAX471/MAX472 require no special bypassing,and respond quickly to transient changes in line cur-rent. If the noise at OUT caused by these transients is a problem, you may want to place a 1µF capacitor at theOUT pin to ground. You can also place a large capaci-tor at the RS- terminal (or “load” side of the MAX472) to decouple the load and, thereby, reduce the current transients. These capacitors are not required forMAX471/MAX472 operation or stability, and their usewill not degrade performance.For the MAX472, the RG1 and RG2 inputs can be fil-tered by placing a capacitor (e.g., 1µF) between themto average the sensed current.MAX471 LayoutThe MAX471 must be soldered in place, since socketscan cause uneven current sharing between the RS+pins (pins 2 and 3) and the RS- pins (pins 6 and7), resulting in typical errors of 0.5%.In order to dissipate sense-resistor heat from largesense currents, solder the RS+ pins and the RS- pins tolarge copper traces. Keep the part away from otherheat-generating devices. This procedure will ensure continuous power dissipation rating.MAX471/MAX472 Precision, High-SideCurrent-Sense Amplifiers ______________________________________________________________________________________11Maxim 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.12__________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 (408) 737-7600©1996 Maxim Integrated ProductsPrinted USAis a registered trademark of Maxim Integrated Products.M A X 471/M A X 472Precision, High-SideCurrent-Sense Amplifiers ____Pin Configurations (continued)。