MAX488ECSA-T中文资料 - 360文档中心

MAX483ESA+T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 .)。

MEMORY存储芯片MAX488EESA+T中文规格书

±15kV ESD-Protected, Slew-Rate-Limited,Low-Power, RS-485/RS-422 Transceivers__________Function Tables (MAX481E/MAX483E/MAX485E/MAX487E/MAX1487E) Table 1. Transmitting Table 2. Receiving__________Applications Information The MAX481E/MAX483E/MAX485E/MAX487E–MAX491E and MAX1487E are low-power transceivers for RS-485 and RS-422 communications. These “E” versions of the MAX481, MAX483, MAX485, MAX487–MAX491, and MAX1487 provide extra protection against ESD. The rugged MAX481E, MAX483E, MAX485E, MAX497E–MAX491E, and MAX1487E are intended for harsh envi-ronments where high-speed communication is important. These devices eliminate the need for transient suppres-sor diodes and the associated high capacitance loading. The standard (non-“E”) MAX481, MAX483, MAX485, MAX487–MAX491, and MAX1487 are recommended for applications where cost is critical.The MAX481E, MAX485E, MAX490E, MAX491E, and MAX1487E can transmit and receive at data rates up to 2.5Mbps, while the MAX483E, MAX487E, MAX488E, and MAX489E are specified for data rates up to 250kbps. The MAX488E–MAX491E are full-duplex transceivers, while the MAX481E, MAX483E, MAX487E, and MAX1487E are half-duplex. In addition, driver-enable (DE) and receiver-enable (RE) pins are included on the MAX481E, MAX483E, MAX485E, MAX487E, MAX489E, MAX491E, and MAX1487E. When disabled, the driver and receiver outputs are high impedance.±15kV ESD Protection As with all Maxim devices, ESD-protection structures are incorporated on all pins to protect against electro-static discharges encountered during handling and assembly. The driver outputs and receiver inputs have extra protection against static electricity. Maxim’s engi-neers developed state-of-the-art structures to protect these pins against ESD of ±15kV without damage. The ESD structures withstand high ESD in all states: normal operation, shutdown, and powered down. After an ESD event, Maxim’s MAX481E, MAX483E, MAX485E, MAX487E–MAX491E, and MAX1487E keep working without latchup.ESD protection can be tested in various ways; the transmitter outputs and receiver inputs of this product family are characterized for protection to ±15kV using the Human Body Model.Other ESD test methodologies include IEC10004-2 con-tact discharge and IEC1000-4-2 air-gap discharge (for-merly IEC801-2).ESD Test Conditions ESD performance depends on a variety of conditions. Contact Maxim for a reliability report that documents test set-up, test methodology, and test results.Human Body Model F igure 4 shows the Human Body Model, and F igure 5 shows the current waveform it generates when dis-charged into a low impedance. This model consists of a 100pF capacitor charged to the ESD voltage of inter-est, which is then discharged into the test device through a 1.5kΩresistor.IEC1000-4-2 The IEC1000-4-2 standard covers ESD testing and per-formance of finished equipment; it does not specifically refer to integrated circuits (Figure 6).MAX481E/MAX483E/MAX485E/MAX487E–MAX491E/MAX1487E Maxim Integrated9±15kV ESD-Protected, Slew-Rate-Limited, Low-Power, RS-485/RS-422 TransceiversThe major difference between tests done using the Human Body Model and IEC1000-4-2 is higher peak current in IEC1000-4-2, because series resistance is lower in the IEC1000-4-2 model. Hence, the ESD with-stand voltage measured to IEC1000-4-2 is generally lower than that measured using the Human Body Model. Figure 7 shows the current waveform for the 8kV IEC1000-4-2 ESD contact-discharge test.The air-gap test involves approaching the device with a charged probe. The contact-discharge method connects the probe to the device before the probe is energized.Machine Model The Machine Model for ESD tests all pins using a 200pF storage capacitor and zero discharge resis-tance. Its objective is to emulate the stress caused by contact that occurs with handling and assembly during manufacturing. Of course, all pins require this protec-tion during manufacturing—not just inputs and outputs. Therefore,after PC board assembly,the Machine Model is less relevant to I/O ports.MAX487E/MAX1487E:128 Transceivers on the Bus The 48kΩ, 1/4-unit-load receiver input impedance of the MAX487E and MAX1487E allows up to 128 transceivers on a bus, compared to the 1-unit load (12kΩinput impedance) of standard RS-485 drivers (32 transceivers maximum). Any combination of MAX487E/MAX1487E and other RS-485 transceivers with a total of 32 unit loads or less can be put on the bus. The MAX481E, MAX483E, MAX485E, and MAX488E–MAX491E have standard 12kΩreceiver input impedance.MAX483E/MAX487E/MAX488E/MAX489E:Reduced EMI and Reflections The MAX483E and MAX487E–MAX489E are slew-rate limited, minimizing EMI and reducing reflections caused by improperly terminated cables. F igure 16 shows the driver output waveform and its Fourier analy-sis of a 150kHz signal transmitted by a MAX481E, MAX485E, MAX490E, MAX491E, or MAX1487E. High-frequency harmonics with large amplitudes are evident.F igure 17 shows the same information displayed for a MAX483E, MAX487E, MAX488E, or MAX489E transmit-ting under the same conditions. F igure 17’s high-fre-quency harmonics have much lower amplitudes, and the potential for EMI is significantly reduced.Low-Power Shutdown Mode(MAX481E/MAX483E/MAX487E) 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 0.5µA 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.F or the MAX481E, MAX483E, and MAX487E, the t ZH and t ZL enable times assume the part was not in the low-power shutdown state (the MAX485E, MAX488E–MAX491E, and MAX1487E can not be shut down). The t ZH(SHDN)and t ZL(SHDN)enable times assume the parts were shut down (see Electrical Characteristics).Figure 16. Driver Output Waveform and FFT Plot of MAX485E/MAX490E/MAX491E/MAX1487E Transmitting a 150kHz SignalFigure 17. Driver Output Waveform and FFT Plot ofMAX483E/MAX487E–MAX489E Transmitting a 150kHz SignalMAX481E/MAX483E/MAX485E/ MAX487E–MAX491E/MAX1487E 12。

max3485中文资料

max3485中文资料max3485eesa + T概述Max3485eesa + T是3.3V电源±15kV ESD保护，真正的RS485 / RS422收发器，采用8引脚nsoic封装。

该低功耗收发器包含一个驱动器和一个接收器。

max3485e传输速率高达15Mbps。

它具有增强的静电保护。

所有发送器输出和接收器输入均具有±15kV保护，并通过IEC 1000-4-2气隙放电；±8Kv保护是通过IEC 1000-4-2接触放电，±15kV保护是通过人体模型。

驱动器受到短路电流的限制，并通过将驱动器输出置于高阻抗状态的热关断电路来防止过多的功耗。

接收器输入具有故障安全功能，如果两个输入均打开，则提供逻辑高电平输出。

Max3485e适用于EMI敏感应用，集成服务，数字网络和数据包交换电源电压范围：3V至3.6V工作温度范围-40°C至85°C半双工通讯该操作由单个+ 3.3V电源供电，无电荷泵兼容+ 5V逻辑2Na小电流关闭模式共模输入电压范围：-7V至+ 12V工业标准75176引脚输出驱动器/接收器启用功能工业控制LAN，ISDN，低功耗RS-485 / RS-422收发器;分组交换;电信;用于EMI敏感应用的收发器Max3483，max3485，max3486，max3488，max3490和max3491是用于RS-485和RS-422通信的3.3V低功耗收发器，每个收发器都有一个驱动器和一个接收器。

Max3483和max3488具有有限速率驱动器，可以降低EMI并减少由于端子匹配电缆不合适而引起的反射，从而实现高达250kbps的无错误数据传输。

由于其有限的摆幅速率，Max3486可以实现最大2.5mbps 的传输速率。

Max3485，max3490和max3491可以实现高达10Mbps的传输速率。

驱动器具有短路电流限制，并且可以通过热关断电路将驱动器的输出设置为高阻状态，以防止过多的功率损耗。

MAX485EESA+T中文资料

________________________________________________________________ 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 .
Next-Generation Device Features
♦ For Fault-Tolerant Applications: MAX3430: ±80V Fault-Protected, Fail-Safe, 1/4Unit Load, +3.3V, RS-485 Transceiver MAX3080–MAX3089: Fail-Safe, High-Speed (10Mbps), Slew-Rate-Limited, RS-485/RS-422 Transceivers
Ordering Information
PART MAX481ECPA MAX481ECSA MAX481EEPA MAX481EESA MAX483ECPA MAX483ECSA MAX483EEPA MAX483EESA
TEMP RANGE 0°C to +70°C 0°C to +70°C -40°C to +85°C -40°C to +85°C 0°C to +70°C 0°C to +70°C -40°C to +85°C -40°C to +85°C
The MAX487E and MAX1487E feature quarter-unit-load receiver input impedance, allowing up to 128 transceivers on the bus. The MAX488E–MAX491E are designed for full-duplex communications, while the MAX481E, MAX483E, MAX485E, MAX487E, and MAX1487E are designed for half-duplex applications. For applications that are not ESD sensitive see the pinand function-compatible MAX481, MAX483, MAX485, MAX487–MAX491, and MAX1487.

MAX488ESA-T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 .)。

MAX487ESA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 .)。

max485esa中文资料

General DescriptionThe MAX481, MAX483, MAX485, MAX487–MAX491, andMAX1487 are low-power transceivers for RS-485 and RS-422 communication. Each part contains one driver and onereceiver. The MAX483, MAX487, MAX488, and MAX489feature reduced slew-rate drivers that minimize E MI andreduce 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 totransmit up to 2.5Mbps.These transceivers draw between 120µA and 500µA ofsupply current when unloaded or fully loaded with disableddrivers. Additionally, the MAX481, MAX483, and MAX487have a low-current shutdown mode in which they consumeonly 0.1µA. All parts operate from a single 5V supply.Drivers are short-circuit current limited and are protectedagainst excessive power dissipation by thermal shutdowncircuitry that places the driver outputs into a high-imped-ance state. The receiver input has a fail-safe feature thatguarantees a logic-high output if the input is open circuit.The MAX487 and MAX1487 feature quarter-unit-loadreceiver input impedance, allowing up to 128 MAX487/MAX1487 transceivers on the bus. Full-duplex communi-cations are obtained using the MAX488–MAX491, whilethe MAX481, MAX483, MAX485, MAX487, and MAX1487are designed for half-duplex applications.________________________Applications Low-Power RS-485 Transceivers Low-Power RS-422 Transceivers Level Translators Transceivers for EMI-Sensitive Applications Industrial-Control Local Area Networks__Next Generation Device Features o For Fault-Tolerant Applications MAX3430: ±80V Fault-Protected, Fail-Safe, 1/4Unit Load, +3.3V, RS-485 Transceiver MAX3440E–MAX3444E: ±15kV ESD-Protected,±60V Fault-Protected, 10Mbps, Fail-Safe, RS-485/J1708 Transceivers o For Space-Constrained Applications MAX3460–MAX3464: +5V, Fail-Safe, 20Mbps,Profibus RS-485/RS-422 Transceivers MAX3362: +3.3V, High-Speed, RS-485/RS-422Transceiver in a SOT23 Package MAX3280E–MAX3284E: ±15kV ESD-Protected,52Mbps, +3V to +5.5V, SOT23, RS-485/RS-422,True Fail-Safe Receivers MAX3293/MAX3294/MAX3295: 20Mbps, +3.3V,SOT23, RS-485/RS-422 Transmitters o For Multiple Transceiver Applications MAX3030E–MAX3033E: ±15kV ESD-Protected,+3.3V, Quad RS-422 Transmitters o For Fail-Safe Applications MAX3080–MAX3089: Fail-Safe, High-Speed (10Mbps), Slew-Rate-Limited RS-485/RS-422Transceiverso For Low-Voltage ApplicationsMAX3483E/MAX3485E/MAX3486E/MAX3488E/MAX3490E/MAX3491E: +3.3V Powered, ±15kVESD-Protected, 12Mbps, Slew-Rate-Limited,True RS-485/RS-422 Transceivers For pricing, delivery, and ordering information, please contact Maxim Direct at1-888-629-4642, or visit Maxim Integrated’s website at .______________________________________________________________Selection Table19-0122; Rev 10; 9/14PARTNUMBERHALF/FULL DUPLEX DATA RATE (Mbps) SLEW-RATE LIMITED LOW-POWER SHUTDOWN RECEIVER/DRIVER ENABLE QUIESCENT CURRENT (μA) NUMBER OF RECEIVERS ON BUS PIN COUNT MAX481Half 2.5No Yes Yes 300328MAX483Half 0.25Yes Yes Yes 120328MAX485Half 2.5No No Yes 300328MAX487Half 0.25Yes Yes Yes 1201288MAX488Full 0.25Yes No No 120328MAX489Full 0.25Yes No Yes 1203214MAX490Full 2.5No No No 300328MAX491Full 2.5No No Yes 3003214MAX1487 Half 2.5No No Yes 2301288Ordering Information appears at end of data sheet.找电子元器件上宇航军工MAX481/MAX483/MAX485/MAX487–MAX491/MAX1487Low-Power, Slew-Rate-LimitedRS-485/RS-422 TransceiversPackage Information For the latest package outline information and land patterns, go to . Note that a “+”, “#”, or “-”in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status.16Low-Power, Slew-Rate-Limited RS-485/RS-422 TransceiversMAX481/MAX483/MAX485/MAX487–MAX491/MAX1487Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent licenses are implied. Maxim Integrated reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits) shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance.Maxim Integrated 160 Rio Robles, San Jose, CA 95134 USA 1-408-601-100017©2014 Maxim Integrated Products, Inc.Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc.。

MAX4828ELT-T中文资料

General DescriptionThe MAX4826–MAX4831 family of switches has internal current limiting to prevent host devices from being damaged due to faulty load conditions. These analog switches have a low 0.7Ωon-resistance and operate from a +2.3V to +5.5V input voltage range. These devices are available with guaranteed 50mA and 100mA current limits, making them ideal for load-switching applications. In addition to the current-limit fault flag (FFLG ), an open-drain no-load flag indicator (NOLD) notifies the system when the current through the switch is less than 10mA (MAX4826–MAX4829), or 5mA (MAX4830/MAX4831).When the switch is on and a load is connected to the port, a guaranteed blanking time of 14ms ensures that the transient voltages settle down. If, after this blanking time, the load current is greater than the current limit,the MAX4826/MAX4828/MAX4830 enter a latch-off state where the switch is turned off, and FFLG is issued to the microprocessor. The switch can be turned on again by cycling the power or ON.The MAX4827/MAX4829/MAX4831 have an autoretry feature where the switch turns off after the blanking time, and then continuously checks to see if the over-load condition is present. The current-limit fault flag (FFLG ) is issued and remains low until after the fault condition is removed. The switch remains on after the overload condition disappears.The MAX4826–MAX4831 operate over the extended -40°C to +85°C temperature range, and are available in a tiny space-saving, 1mm x 1.5mm, 6-pin µDFN package.Features♦Guaranteed Current Limit: 50mA, 100mA♦Thermal Shutdown Protection ♦Reverse-Current Protection♦0.7ΩOn-Resistance (MAX4826–MAX4831)♦14ms Guaranteed Blanking Time ♦Fault Flag (FFLG )♦No-Load Flag (NOLD )♦65µA Supply Current ♦8µA Latch-Off Current ♦0.01µA Shutdown Current ♦+2.3V to +5.5V Supply Range ♦Undervoltage Lockout♦Fast Current-Limit Response Time ♦6-Pin µDFN Package (1mm x 1.5mm)ApplicationsGPS Systems Cell Phones Digital Still Cameras PDAs and Palmtop Devices MP3 PlayersMAX4826–MAX483150mA/100mA Current-Limit Switches withNO-LOAD Flag in µDFN________________________________________________________________Maxim Integrated Products1Ordering Information/Selector Guide19-3672; Rev 0; 5/05For pricing, delivery, and ordering information,please contact Maxim/Dallas Direct!at 1-888-629-4642, or visit Maxim’s website at .*Future product—contact factory for availability.Pin Configuration appears at end of data sheet.M A X 4826–M A X 483150mA/100mA Current-Limit Switches with NO-LOAD Flag in µDFN 2_______________________________________________________________________________________ABSOLUTE MAXIMUM RATINGSStresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.IN, ON, FFLG , NOLD , OUT to GND .........................-0.3V to +6V OUT Short Circuit to GND.................................Internally Limited Continuous Power Dissipation (T A = +70°C)6-Pin µDFN (derate 2.1mW/C above +70°C)...............168mW Operating Temperature Range ...........................-40°C to +85°CJunction Temperature......................................................+150°C Storage Temperature Range.............................-65°C to +150°C Lead Temperature (soldering, 10s).................................+300°CELECTRICAL CHARACTERISTICS(V IN = +2.3V to +5.5V, T A = -40°C to +85°C, unless otherwise noted. Typical values are at V IN = +3.3V, T A = +25°C.) (Note 1)MAX4826–MAX483150mA/100mA Current-Limit Switches withNO-LOAD Flag in µDFN_______________________________________________________________________________________3ELECTRICAL CHARACTERISTICS (continued)(V IN = +2.3V to +5.5V, T A = -40°C to +85°C, unless otherwise noted. Typical values are at V IN = +3.3V, T A = +25°C.) (Note 1)Note 2:Latch-off current does not include the current flowing into FFLG and NOLD .Note 3:Turn-on time is defined as the time taken for the current through the switch to go from 0mA to full load. Turn-off time isdefined as the time taken for the current through the switch to go from full load to 0mA.Note 4:Retry time is typically 14x the blanking time.Typical Operating Characteristics(V IN = +3.3V, T A = +25°C, unless otherwise noted.)QUIESCENT SUPPLY CURRENTvs. SUPPLY VOLTAGESUPPLY VOLTAGE (V)S U P P L Y C U R R E N T (µA )5.14.73.9 4.33.1 3.52.710203040506070809002.3 5.5TEMPERATURE (°C)603510-15-4085QUIESCENT SUPPLY CURRENTvs. TEMPERATURES U P P L Y C U R R E N T (µA )10203040506070809001234567891011121314150TEMPERATURE (°C)603510-15-4085LATCH-OFF CURRENT vs. TEMPERATUREL A T C H -O F F C U R R E N T (µA )M A X 4826–M A X 483150mA/100mA Current-Limit Switches with NO-LOAD Flag in µDFN 4_______________________________________________________________________________________Typical Operating Characteristics (continued)(V IN = +3.3V, T A = +25°C, unless otherwise noted.)SHUTDOWN SUPPLY CURRENTvs. TEMPERATURETEMPERATURE (°C)S H U T D O W N S U P P L Y C U R R E N T (n A )0.0010.010.11100.0001603510-15-4085SHUTDOWN LEAKAGE CURRENTvs. TEMPERATURETEMPERATURE (°C)S H U T D O W N L E A K A G E C U R R E N T (n A )0.0010.010.11100.0001603510-15-4085SHUTDOWN REVERSE LEAKAGE CURRENTvs. TEMPERATURETEMPERATURE (°C)R E V E R S E L E A K A G E C U R R E N T (n A )0.0010.010.11100.0001603510-15-4085LATCH-OFF-LEAKAGE CURRENTvs. TEMPERATURETEMPERATURE (°C)L A T C H -O F F -L E A K A G E C U R R E N T (n A )0.0010.010.11100.0001603510-15-4085TEMPERATURE (°C)603510-15-4085NORMALIZED ON-RESISTANCEvs. TEMPERATUREN O R M A L I Z E D R O N0.20.40.60.81.01.21.4010050200150********.60.9 1.20.3 1.5 1.8 2.1 2.4 2.7 3.0 3.3OUTPUT CURRENT vs. OUTPUT VOLTAGEV IN - V OUT (V)O U T P U T C U R R E N T (m A )SWITCH TURN-ON/OFF TIMESvs. TEMPERATURETEMPERATURE (°C)T U R N -O N /O F F T I M E S (µs )0.010.11101000.001603510-15-4085FLAG-BLANKING TIMEOUT vs. TEMPERATUREF L AG -B L A N K I N G T I M E (m s )15202530354010M A X 4826 t o c 11TEMPERATURE (°C)603510-15-4085MAX4826–MAX483150mA/100mA Current-Limit Switches withNO-LOAD Flag in µDFN_______________________________________________________________________________________5CURRENT-LIMIT RESPONSE40µs/div V ON = 3.3V V OUT = GND C IN = 1µF C OUT = 1µFV IN 2V/div V ON 2V/divI OUT100mA/div CURRENT-LIMIT RESPONSE (OUT SHORTED TO GND)MAX4826 toc1440µs/divV IN 2V/div V OUT 2V/divI OUT 2A/divCURRENT-LIMIT RESPONSEMAX4826 toc1320µs/divV ON = 3.3V V OUT = GND C IN = 1µF C OUT = 1µFV IN = V ON 1V/divI OUT100mA/divSWITCH TURN-ON-TIME RESPONSE100µs/divV IN = 3.3V I LOAD = 10mAV ON 2V/divI OUT100mA/divTypical Operating Characteristics (continued)(V IN = +3.3V, T A = +25°C, unless otherwise noted.)SWITCH TURN-OFF-TIME RESPONSE100ns/divV ON 2V/divI OUT10mA/divV IN = 3.3V I LOAD = 10mAFLAG-BLANKING RESPONSEMAX4826 toc174ms/divV IN 2V/divV ON 2V/divI OUT100mA/divFFLG 2V/divM A X 4826–M A X 4831Detailed DescriptionThe MAX4826–MAX4831 are forward-/reverse-current-limited switches that operate from a +2.3V to +5.5V input voltage range and guarantee a 50mA and 100mA minimum current-limit threshold for different options.The voltage drop across an internal sense resistor is compared to two reference voltages to indicate a for-ward- or reverse-current-limit fault. When the load cur-rent exceeds the preset current limit for greater than the fault-blanking time, the switch opens.The MAX4827/MAX4829/MAX4831 have an autoretry function that turns on the switch again after an internal retry time expires. If the faulty load condition is still pre-sent after the blanking time, the switch turns off again and the cycle is repeated. If the faulty load condition is not present, the switch remains on.The MAX4826/MAX4828/MAX4830 do not have the autoretry option, and the switch remains in latch-off mode until ON or the input power is cycled from high to low and then high again.The undervoltage lockout (UVLO) circuit prevents erro-neous switch operation when the input voltage goes too low during startup conditions.The MAX4826–MAX4831 limit the reverse current (V OUT to V IN ) from exceeding the maximum I REV value. The switch is shut off and FFLG is asserted if the reverse-current-limit condition persists for more than the blank-ing time. This feature prevents excessive reverse cur-rents from flowing through the device.Switch-On/Off ControlToggle ON high to enable the current-limited switches.The switches are continuously on only if V IN exceeds the UVLO threshold (typically 2V) and there is no fault.When a forward-/reverse-current fault is present or the die exceeds the thermal-shutdown temperature of +150°C, OUT is internally disconnected from IN, and the supply current decreases to 8µA (latch off). The switch is now operating in one of its off states. The switch off state also occurs when driving ON low, thus reducing the supply current (shutdown) to 0.01µA.Table 1 illustrates the ON/OFF state of the MAX4826–MAX4831 current-limit switches.50mA/100mA Current-Limit Switches with NO-LOAD Flag in µDFNFFLG IndicatorThe MAX4826–MAX4831 feature a current-limit fault output, FFLG . Whenever a current-limit fault is activat-ed, FFLG goes low and the switch turns off. FFLG is an open-drain output transistor and requires an external pullup resistor from FFLG to IN. During shutdown (ON is low), the pulldown on the FFLG output is released to limit power dissipation. FFLG goes low when any of the following conditions occur:• The die temperature exceeds the thermal shut-down temperature limit of +150°C.• The device is in current limit for more than the fault-blanking period.• V IN is below the UVLO threshold.NOLD IndicatorThe MAX4826–MAX4831 feature a no-load flag output,NOLD (Figure 1). This output is pulled low every time the current coming out of the switch is less than 10mA (MAX4826–MAX4829), or 5mA (MAX4830/MAX4831).NOLD is an open-drain output transistor and requires an external pullup resistor from NOLD to a supply up to +5.5V. Current through the switch is intended to be positive (from IN to OUT), and for currents that are large in magnitude but negative in sign (OUT to IN),NOLD asserts low. For options with the autoretry fea-ture (MAX4827/MAX4829/MAX4831), the NOLD output is high impedance during the t RETRY period when a for-ward-current-limit condition is present. However, NOLD is pulled low if a reverse current-limit condition is pre-sent during the t RETRY period. A constant time filter is present at the output of NOLD that gives a 60µs delay when a no-load condition is asserted. Deassertion of NOLD is not delayed. During shutdown (ON is low), the pulldown on NOLD is released to limit power dissipation.Autorety (MAX4827/MAX4829/MAX4831)When the forward- or reverse-current-limit threshold is exceeded, the t BLANK timer begins counting (Figure 2).The timer resets if the overcurrent condition disappears before t BLANK has elapsed. A retry time delay, t RETRY ,MAX4826–MAX483150mA/100mA Current-Limit Switches withNO-LOAD Flag in µDFN_______________________________________________________________________________________7Figure 3. MAX4826/MAX4828/MAX4830 Latch-Off Fault BlankingFigure 2. MAX4827/MAX4829/MAX4831 Autoretry Fault Blanking DiagramFigure 1. MAX4826–MAX4831 No-Load Flag ResponseM A X 4826–M A X 4831is started immediately after t BLANK has elapsed, and during that time the switch is latched off. At the end of t RETRY , the switch is turned on again. If the fault still exists, the cycle is repeated. If the fault has been removed, the switch stays on.The autoretry feature saves system power in the case of an overcurrent or short-circuit condition. During t BLANK ,when the switch is on, the supply current is at the cur-rent limit. During t RETRY , when the switch is off, no cur-rent flows through the switch. Instead of observing the full load current, the switch sees the equivalent load current, multiplied by the duty cycle or I SUPPLY = I LOAD x t BLANK / (t BLANK + t RETRY ). With a typical t BLANK =37ms and typical t RETRY = 518ms, the duty cycle is 6%which results in a 94% power savings, as opposed to the switch being on the entire time. The duty cycle is consistent across the process and devices.Latch Off (MAX4826/MAX4828/MAX4830)When the forward- or reverse-current-limit threshold is exceeded, the t BLANK timer begins counting. The timer resets if the overcurrent condition disappears before t BLANK has elapsed. The switch is shut off if the over-current condition continues up to the end of the blank-ing time. Reset the switch by either toggling ON (Figure 3a), or cycling the input voltage below UVLO, typically 2V (Figure 3b).Fault BlankingThe MAX4826–MAX4831 feature 14ms (min) fault blank-ing. Fault blanking allows current-limit faults, including momentary short-circuit faults that occur when hot swap-ping a capacitive load. Fault blanking also ensures that no fault is issued during power-up. When a load transient causes the device to enter the current limit, an internal counter starts. If the load-transient fault persists beyond the fault-blanking timeout, FFLG asserts low. Load-tran-sient faults less than t BLANK do not cause FFLG asser-tion. Only current-limit faults are blanked.A thermal fault and input voltage drops below the UVLO threshold cause FFLG to assert immediately. These faults do not wait for the blanking time.Thermal ShutdownThe MAX4826–MAX4831 have a thermal-shutdown fea-ture to protect the devices from overheating. The switch turns off and FFLG goes low immediately (no fault blanking) when the junction temperature exceeds +150°C. The switches with the autoretry feature turn back on when the device temperature drops approxi-mately 15°C. The switches with the latch-off feature require ON cycling.Applications InformationInput CapacitorTo limit the input voltage drop during momentary output short-circuit conditions, connect a capacitor from IN to GND. A 0.1µF ceramic capacitor is adequate for most applications; however, higher capacitor values further reduce the voltage drop at the input and are recom-mended for lower voltage applications.Output CapacitanceConnect a 0.1µF capacitor from OUT to GND. This capacitor helps prevent inductive parasitics from pulling OUT negative during turn-off, thus preventing the MAX4826–MAX4831 from tripping erroneously. If the load capacitance is too large, current may not have enough time to charge the capacitance, and the device assumes that there is a faulty load condition. The maxi-mum capacitive load value that can be driven from OUT is obtained by the following formula:Layout and Thermal DissipationTo optimize the switch response time to output short-circuit conditions, it is very important to keep all traces as short as possible to reduce the effect of undesirable parasitic inductance. Place input and output capacitors as close as possible to the device (no more than 5mm).IN and OUT pins must be connected with short traces to the power bus.During normal operation, the power dissipation is small and the package temperature change is minimal. If the output is continuously shorted to ground at the maxi-mum supply voltage, the operation of the switches with the autoretry option does not cause problems because the total power dissipated during the short is scaled by the duty cycle:where,V IN_MAX = 5.5V, I OUT_MAX = 240mA, t BLANK = 37ms,and t RETRY = 518ms.Attention must be given to the MAX4826/MAX4828/MAX4830 where the latch-off condition must be manually reset by toggling ON from high to low. If the latch-off time duration is not sufficiently high, it is possible for the device to reach the thermal shutdown threshold andnever be able to turn the device on until it cools down.50mA/100mA Current-Limit Switches with NO-LOAD Flag in µDFN 8_______________________________________________________________________________________MAX4826–MAX483150mA/100mA Current-Limit Switches withNO-LOAD Flag in µDFNChip InformationTRANSISTOR COUNT: 1175PROCESS: BiCMOSPin ConfigurationTypical Operating CircuitFunctional DiagramM A X 4826–M A X 483150mA/100mA Current-Limit Switches with NO-LOAD Flag in µDFN Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.10____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600©2005 Maxim Integrated ProductsPrinted USAis a registered trademark of Maxim Integrated Products, Inc.MAX4826–MAX4831Package 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 .)6L U D F N .E P S。

MAX1487EESA中文资料

元器件交易网
MAX481E/MAX483E/MAX485E/MAX487E–/MAX1487E
±15kV ESD-Protected, Slew-Rate-Limited, Low-Power, RS-485/RS-422 Transceivers
ABSOLUTE MAXIMUM RATINGS
Driver Input Voltage (DI).............................-0.5V to (VCC + 0.5V)
Driver Output Voltage (Y, Z; A, B) ..........................-8V to +12.5V
Receiver Input Voltage (A, B).................................-8V to +12.5V
Applications
Low-Power RS-485 Transceivers
Low-Power RS-422 Transceivers
Level Translators
Transceivers for EMI-Sensitive Applications
Industrial-Control Local Area Networks
The MAX487E and MAX1487E feature quarter-unit-load receiver input impedance, allowing up to 128 transceivers on the bus. The MAX488E–MAX491E are designed for full-duplex communications, while the MAX481E, MAX483E, MAX485E, MAX487E, and MAX1487E are designed for half-duplex applications. For applications that are not ESD sensitive see the pinand function-compatible MAX481, MAX483, MAX485, MAX487–MAX491, and MAX1487.

MAX4785-MAX4788中文资料

Applications
PDAs and Palmtop Devices
Cell Phones
GPS Systems
Hand-Held Devices
TOP VIEW
Pin Configurations
OUT 1 GND 2 FLAG 3
MAX4785 MAX4787
5 IN 4 ON
OUT 1 GND 2
Turn-Off Time (Note 3)
SYMBOL VIN IQ
ILATCH ISHDN IFWD IREV
UVLO
CONDITIONS
VON = VIN, IOUT = 0, VIN = 2.3V to 5.0V
switch on
VIN = 5.0V to 5.5V
VON = VIN, after an overcurrent fault (MAX4785/MAX4787)
4-Pin SC70 (derate 3.1mW/°C above +70°C) ..............245mW 5-Pin SC70 (derate 3.1mW/°C above +70°C) ..............247mW
Operating Temperature Range ...........................-40°C to +85°C Junction Temperature ......................................................+150°C Storage Temperature Range .............................-65°C to +150°C Lead Temperature (soldering, 10s) .................................+300°C

启珑微电子产品手册说明书

产品手册PRODUCT MANUAL(北京︶有限公司并一直致力于为工业智能控制、医疗设备、轨道交通、智能交通以及智能家居等领域提供更优质的产品与服务。

公司具有深厚的文化底蕴，由多位有欧美留学、工作经历的归国人员创办，坚实的理论功底和丰富的芯片设计经验奠定了启珑微电子的高起点和高水准，并迅速成长为业内具有自主知识产权的中国IC设计品牌之一。

产品手册01序号产品型号封装形式产品概述兼容型号1CLM811HST-AXC TQFP-48SL811HST-AXC 2CLCP82C55AZ DIP-40CP82C55AZ 3CLIP82C55AZ DIP-40IP82C55AZ 4CLCS82C55AZ PLCC-44CS82C55AZ 5CLIS82C55AZ PLCC-44IS82C55AZ 6CLCQ82C55AZ MQFP-44CQ82C55AZ 7CLIQ82C55AZ MQFP-44IQ82C55AZ 8CLID82C55AZ DIP-40ID82C55A 9CLMD82C55A/B DIP-40MD82C55A/B 10CLMD82C55QA DIP-40MD82C55QA 11CLM65HVD230D SOIC-8SN65HVD230D 12CLM65HVD230QD SOIC-8SN65HVD230QD 13CLM65HVD231D SOIC-8SN65HVD231D 14CLM65HVD231QD SOIC-8SN65HVD231QD 15CLM65HVD232D SOIC-8SN65HVD232D 16CLM65HVD232QD SOIC-8SN65HVD232QD 17CLM65HVD233D SOIC-8具有待机模式和环回功能的 3.3V SN65HVD233D 18CLM65HVD233HD SOIC-8具有待机模式和环回功能的 3.3V SN65HVD233HD 19CLM65HVD233QDRQ1SOIC-8具有待机模式和环回功能的 3.3V SN65HVD233QDRQ120CLM65HVD233MDREP SOIC-8具有待机模式和环回功能的 3.3V SN65HVD233MDREP产品手册02序号产品型号封装形式产品概述兼容型号21CLM65HVD234D SOIC-8SN65HVD234D 22CLM65HVD234QDRQ1SOIC-8SN65HVD234QDRQ123CLM65HVD235D SOIC-8SN65HVD235D 24CLM65HVD235QDRQ1SOIC-8SN65HVD235QDRQ125CLM75176BPS SOIC-8SN75176BPSR 26CLM75176BDR SOIC-8SN75176BDR 27CLM75176ADR SOIC-8SN75176ADR 28CLM75176AP DIP-8SN75176AP 29CLM76176BP DIP-8SN75176BP 30CLM75179BPS SOIC-8SN75179BPS 31CLM75179BDR SOIC-8SN75179BDR 32CLM75179AP DIP-8SN75179AP 33CLM75179BP DIP-8SN75179BP 34CLM65HVD08D SOIC-8SN65HVD08D 35CLM65HVD08P DIP-8SN65HVD08P 36CLM65HVD75D SOIC-8具有IEC ESD保护功能和20Mbps的SN65HVD75D 37CLM65HVD75DGK VSSOIC-8具有IEC ESD保护功能和20Mbps的SN65HVD75DGK 38CLM65HVD75DRBT VDFN-8具有IEC ESD保护功能和20Mbps的SN65HVD75DRBT 39CLM3085CPA+DIP-8(10Mbps)、限摆率RS-485/MAX3085CPA+40CLM3085EPA+DIP-8(10Mbps)、限摆率RS-485/MAX3085EPA+产品手册03序号产品型号封装形式产品概述兼容型号41CLM3085EEPA DIP-8(10Mbps)、限摆率RS-485/MAX3085EEPA 42CLM3085CSA+T SOIC-8(10Mbps)、限摆率RS-485/MAX3085CSA+43CLM3085ECSA+T MSOIC-8(10Mbps)、限摆率RS-485/MAX3085ECSA+T 44CLM3085ESA+T SOIC-8(10Mbps)、限摆率RS-485/MAX3085ESA+45CLM3085EESA+T SOIC-8(10Mbps)、限摆率RS-485/MAX3085EESA+46CLM3088CSA+T SOIC-8MAX3088CSA+T 47CLM3088ECSA+T SOIC-8MAX3088ECSA+T 48CLM3088ESA+T SOIC-8MAX3088ESA+T 49CLM3088EESA+T SOIC-8MAX3088EESA+T 50CLM3088CPA+DIP-8MAX3088CPA+51CLM3088ECPA+DIP-8MAX3088ECPA+52CLM3088EPA+DIP-8MAX3088EPA+53CLM3088EEPA+DIP-8MAX3088EEPA+54CLM485CPA+DIP-8低功耗、限摆率、RS-485/RS-422MAX485CPA+55CLM485ECPA+DIP-8低功耗、限摆率、RS-485/RS-422MAX485ECPA+56CLM485EPA+DIP-8低功耗、限摆率、RS-485/RS-422MAX485EPA+57CLM485EEPA+DIP-8低功耗、限摆率、RS-485/RS-422MAX485EEPA+58CLM485CSA+SOIC-8低功耗、限摆率、RS-485/RS-422MAX485CSA+59CLM485ESA+SOIC-8低功耗、限摆率、RS-485/RS-422MAX485ESA+60CLM485EESA+SOIC-8低功耗、限摆率、RS-485/RS-422MAX485EESA+产品手册04序号产品型号封装形式产品概述兼容型号61CLM3490CSA+SOIC-8 3.3V供电、10Mbps、限摆率、真MAX3490CSA+62CLM3490ECSA+SOIC-8 3.3V供电、10Mbps、限摆率、真MAX3490ESA+63CLM3490ESA+SOIC-8 3.3V供电、10Mbps、限摆率、真MAX3490ESA+64CLM3490EESA+SOIC-8 3.3V供电、10Mbps、限摆率、真MAX3490EESA+65CLM3491CSD SOP-14 3.3V供电、10Mbps、限摆率、真MAX3491CSD+66CLM3491ECSD+SOP-14 3.3V供电、10Mbps、限摆率、真MAX3491ECSD+67CLM3491ESD+SOP-14 3.3V供电、10Mbps、限摆率、真MAX3491ESD+68CLM3491EESD+SOP-14 3.3V供电、10Mbps、限摆率、真MAX3491EESD+69CLM490CSA+SOIC-8低功耗、限摆率、RS-485/RS-422MAX490CSA+70CLM490ECSA+SOIC-8低功耗、限摆率、RS-485/RS-422MAX490ECSA+71CLM490ESA+SOIC-8低功耗、限摆率、RS-485/RS-422MAX490ESA+72CLM490EESA+SOIC-8低功耗、限摆率、RS-485/RS-422MAX490EESA+73CLM490CPA+DIP-8低功耗、限摆率、RS-485/RS-422MAX490CPA+74CLM490ECPA+DIP-8低功耗、限摆率、RS-485/RS-422MAX490ECPA+75CLM490EPA+DIP-8低功耗、限摆率、RS-485/RS-422MAX490EPA+76CLM490EEPA+DIP-8低功耗、限摆率、RS-485/RS-422MAX490EEPA+77CLM488CSA+SOIC-8低功耗、限摆率、RS-485/RS-422MAX488CSA+78CLM488ECSA+SOIC-8低功耗、限摆率、RS-485/RS-422MAX488ECSA+79CLM488ESA+SOIC-8低功耗、限摆率、RS-485/RS-422MAX488ESA+80CLM488EESA+SOIC-8低功耗、限摆率、RS-485/RS-422MAX488EESA+产品手册序号产品型号封装形式产品概述兼容型号81CLM488CPA+DIP-8MAX488CPA+82CLM488ECPA+DIP-8MAX488ECPA+83CLM488EPA+DIP-8MAX488EPA+84CLM488EEPA+DIP-8MAX488EEPA+85CLM232CSE SOIC-16MAX232CSE+T86CLM232ECSE SOIC-16MAX232ECSE+87CLM232ESE SOIC-16MAX232ESE+T88CLM232EESE SOIC-16MAX232EESE+T89CLM232CPE DIP-16MAX232CPE+90CLM232ECPE DIP-16MAX232ECPE+91CLM232EPE DIP-16MAX232EPE+92CLM232EEPE DIP-16MAX232EEPE+93CLM232CWE SOIC-16MAX232CWE+T94CLM232ECWE SOIC-16MAX232ECWE+T95CLM232EWE SOIC-16MAX232EWE+T96CLM232EEWE SOIC-16MAX232EEWE+T97CLM232ACWE SOIC-16MAX232ACWE+T98CLM232AEWE SOIC-16MAX232AEWE+99CLM3232CSE SOIC-16MAX3232CSE+T 100CLM3232ECSE SOIC-16MAX3232ECSE+T05产品手册06序号产品型号封装形式产品概述兼容型号101CLM3232ESE SOIC-16MAX3232ESE+T 102CLM3232EESE SOIC-16MAX3232EESE+T 103CLM1302S SOIC-8DS1302S+T&R 104CLM1302SN+SOIC-8DS1302SN+T&R 105CLM1302Z+T SOIC-8DS1302Z+T&R 106CLM1302ZN+SOIC-8DS1302ZN+T&R 107CLM1302+DIP-8DS1302+108CLM1302N+DIP-8DS1302N+109CLM307Z+SOIC-8DS1307Z+T&R 110CLM1307ZN+SOIC-8DS1307ZN+T&R 111CLM1307+DIP-8DS1307+112CLM1307N+DIP-8DS1307N+113CLM4717EUB+MSOP-10拟开关MAX4717EUB+114CLM231N/NOPB DIP-8LM231N/NOPB 115CLM231AN/NOPB DIP-8LM231AN/NOPB 116CLM331N/NOPB DIP-8LM331N/NOPB 117CLM331AN/NOPB DIP-8LM331AN/NOPB 118CLM298N Multiwatt-15L298N 119CLM298P POWERSO-20L298P 120CLM2543CDW SOIC-20TLC2543CDW产品手册07序号产品型号封装形式产品概述兼容型号121CLM2543IDW SOIC-20TLC2543IDW 122CLM2543CDB SSOP-20TLC2543CDB 123CLM2543IDB SSOP-20TLC2543IDB 124CLM2543CN DIP-20TLC2543CN 125CLM2543IN DIP-20TLC2543IN 126CLM1543CDW SOIC-20TLC1543CDW 127CLM1543IDW SOIC-20TLC1543IDW 128CLM1543CN DIP-20TLC1543CN 129CLM1543IN DIP-20TLC1543IN 130CLM5615CDGK VSSOIC-8趋稳时间为12.5us并具备上电复位功能的10位、单通道、低功耗DAC TLC5615CDGK 131CLM5615IDGK VSSOIC-8趋稳时间为12.5us并具备上电复位功能的10位、单通道、低功耗DAC TLC5615IGGK 132CLM5615CD SOIC-8趋稳时间为12.5us并具备上电复位功能的10位、单通道、低功耗DAC TLC5615CD 133CLM5615ID SOIC-8趋稳时间为12.5us并具备上电复位功能的10位、单通道、低功耗DAC TLC5615ID 134CLM5615CP DIP-8趋稳时间为12.5us并具备上电复位功能的10位、单通道、低功耗DAC TLC5615CP 135CLM5615IP DIP-8趋稳时间为12.5us并具备上电复位功能的10位、单通道、低功耗DAC TLC5615IP 136CLM3616-00SOP-14IW3616-00137CLM3616-01SOP-14IW3616-01138CLM3617-00SOP-14IW3617-00139CLM3617-01SOP-14IW3617-01140CLM3630-00SOP-14IW3630-00产品手册序号产品型号封装形式产品概述兼容型号141CLM1100-0001BGA-128ASIC从站控制ET1100-0001142CLM1100-0002BGA-128ASIC从站控制ET1100-0002143CLM1100-0003BGA-128ASIC从站控制ET1100-0003144CLM1200-0001QFN-48ASIC从站控制ET1200-0001145CLM1200-0002QFN-48ASIC从站控制ET1200-0002146CLM1200-0003QFN-48ASIC从站控制ET1200-0003147CLM8656ARZ SOIC-8AD8656ARZ148CLM8656ARMZ MSOIC-8AD8656ARMZ149CLM1040T/CM,118SOIC-8TJA1040T/CM,118 150CLM1042T/CM,118SOIC-8TJA1042T/CM,118 151CLM1050T/CM,118SOIC-8TJA1050T/CM,118 152CLM1051T/CM,118SOIC-8TJA1051T/CM,118 153CLM82C250T/YM SOIC-8PCA82C250T/YM 154CLM82C251T/YM SOIC-8PCA82C251T/YM 155CLMEE80C196KC20PLCC-68EE80C196KC20 156CLMEN80C196KC20PLCC-68EN80C196KC20 157CLMN80C196KC20PLCC-68N80C196KC20 158CLMTN80C196KC20PLCC-68TN80C196KC20 159CLMEE87C196KC20PLCC-68EE87C196KC20 160CLMEN87C196KC20PLCC-68EN87C196KC2008产品手册09序号产品型号封装形式产品概述兼容型号161CLMN87C196KC20PLCC-68N87C196KC20162CLMTN87C196KC20PLCC-68TN87C196KC20163CLM8051F020-GQ TQFP-100C8051F020-GQ 164CLM8051F021-GQ TQFP-64C8051F021-GQ 165CLM8051F330-GM VFQFN-20C8051F330-GM 166CLM8051F500-IQ TQFP-48C8051F500-IQ 167CLM8051F500-IM VFQFN-48C8051F500-IM 168CLM8051F502-IQ LQFP-32C8051F502-IQ 169CLM8051F502-IM QFN-32C8051F502-IM170CLM08D1500CIYB/NOPB HLQFP-128ADC08D1500CIYB/NOPB 171CLM083000CIYB/NOPB HLQFP-128ADCADC083000CIYB/NOPB 172CLM10AQ190AVTPY EBGA-38010位5GSPS ADC EV10AQ190AVTPY 173CLM9680BCPZ-1250LFCSP-64双通道14位1GSPS ADC AD9680BCPZ-1250174CLM9739BBCZ BGA-16014位、2.5 GSPS、RF数模AD9739BBCZ 175CLM9779ABSVZ TQFP-100双通道16位1GSPS DAC AD9779ABSVZ 176CLM12DS130AVZPY FPBGA-19612位3GSPS DAC EV12DS130AVZPY 177CLM12DS460AVZP FPBGA-19612位6.4GSPS DAC EV12DS460AVZP 178CLM9434BCPZ-370LFCSP-5612位370MSPS ADC AD9434BCPZ-370179CLM9434BCPZ-500LFCSP-5612位500MSPS ADC AD9434BCPZ-500180CLM4149IRGZTVQFN-4814位250MSPS ADCADS4149IRGZT产品手册10序号产品型号封装形式产品概述兼容型号181CLM9467BCPZ-200LFCSP-7216位200MSPS ADC AD9467BCPZ-200182CLM9467BCPZ-250LFCSP-7216位250MSPS ADC AD9467BCPZ-250183CLM9656BCPZ-125LFCSP-56四通道16位125MSPS ADC AD9656BCPZ-125184CLM9245BCPZ-40LFCSP-3214位40MSPS ADC AD9245BCPZ-40185CLM9245BCPZ-65LFCSP-3214位65MSPS ADC AD9245BCPZ-80186CLM9245BCPZ-80LFCSP-3214位80MSPS ADC AD9245BCPZ-80187CLM9783BCPZ LFCSP-72双通道16位500MSPS DAC AD9783BCPZ 188CLM7656BSTZ-REEL LQFP-64六通道16位250KSPS ADC AD7656BSTZ-REEL 189CLM7960BCPZLFCSP-3218位2MSPS ADC AD7960BCPZ190CLM128S102CIMTX/NOPB TSSOP-1612位1MSPS ADC ADC128S102CIMTX/NOPB 191CLM5638IDR SOIC-8DACTLV5638IDR 192CLM7606BSTZ LQFP-64AD7606BSTZ 193CLM9625BBPZ-2.5BGA-19612位2.6GSPS ADC AD9625BBPZ-2.5194CLM9164BBCZ BGA-16516位12GSPS DAC AD9164BBCZ 195CLM9154BCPZ LFCSP-88四通道16位2.4GSPS DAC AD9154BCPZ 196CLM2160IUK#PBF QFN-4816位25MSPS ADC LTC2160IUK#PBF 197CLM9652BBCZ-310BGA-144双通道16位310MSPS ADC AD9652BBCZ-310198CLM7779ACPZ-RL LFCSP-6424位16KSPS ADC AD7779ACPZ-RL 199CLM9208BBPZ-3000BGA-196双通道14位3GSPS ADCAD9208BBPZ-3000200CLM320VC33PGE120LQFP-144TMS320VC33PGE120产品手册序号产品型号封装形式产品概述兼容型号201CLM320VC33PGEA120LQFP-144TMS320VC33PGEA120 202CLM320VC33PGE150LQFP-144TMS320VC33PGE150203CLM320VC5402PGE100LQFP-144TMS320VC5402PGE100 204CLM320F28335PGFA LQFP-176TMS320F28335PGFA205CLM320LF2406APZA LQFP-100TMS320LF2406APZA206CLM320LF2406APZS LQFP-100TMS320LF2406APZS207CLM320LF2407APGES LQFP-144TMS320LF2407APGES208CLM320LF2407APGEA LQFP-144TMS320LF2407APGEA 209CLM320C6713BPYP200HLQFP-208TMS320C6713BPYP200 210CLM320C6713BZDP225BGA-272TMS320C6713BZDP225 211CLM320C6713BGDP225BGA-272TMS320C6713BGDP225 212CLM320C6713BZDP300BGA-272TMS320C6713BZDP300 213CLM320C6713BGDG300BGA-272TMS320C6713BGDP30011邮箱：*******************。

MAX488E中文资料

______________Ordering Information
PART MAX481ECPA MAX481ECSA
TEMP. RANGE 0°C to +70°C 0°C to +70°C
PIN-PACKAGE 8 Plastic DIP 8 SO
________________________Applications
元器件交易网
MAX481E/MAX483E/MAX485E/MAX487E–MAX491E/MAX1487E
19-0410; Rev 3; 7/96
±15kV ESD-Protected, Slew-Rate-Limited, Low-Power, RS-485/RS-422 Transceivers
Receiver Output Voltage (RO)....................-0.5V to (VCC + 0.5V)
Continuous Power Dissipation (TA = +70°C)
8-Pin Plastic DIP (derate 9.09mW/°C above +70°C) ....727mW
QUIESCENT CURRENT
(µA) 300 120 300 120 120 120 300 300 230
NUMBER OF TRANSMITTERS
ON BUS 32 32 32 128 32 32 32 32 128
PIN COUNT
8 8 8 8 8 14 8 14 8
________________________________________________________________ Maxim Integrated Products 1

MEMORY存储芯片MAX488CPA中文规格书

±15kV ESD-Protected, Slew-Rate-Limited, Low-Power, RS-485/RS-422 TransceiversThe major difference between tests done using the Human Body Model and IEC1000-4-2 is higher peak current in IEC1000-4-2, because series resistance is lower in the IEC1000-4-2 model. Hence, the ESD with-stand voltage measured to IEC1000-4-2 is generally lower than that measured using the Human Body Model. Figure 7 shows the current waveform for the 8kV IEC1000-4-2 ESD contact-discharge test.The air-gap test involves approaching the device with a charged probe. The contact-discharge method connects the probe to the device before the probe is energized.Machine Model The Machine Model for ESD tests all pins using a 200pF storage capacitor and zero discharge resis-tance. Its objective is to emulate the stress caused by contact that occurs with handling and assembly during manufacturing. Of course, all pins require this protec-tion during manufacturing—not just inputs and outputs. Therefore,after PC board assembly,the Machine Model is less relevant to I/O ports.MAX487E/MAX1487E:128 Transceivers on the Bus The 48kΩ, 1/4-unit-load receiver input impedance of the MAX487E and MAX1487E allows up to 128 transceivers on a bus, compared to the 1-unit load (12kΩinput impedance) of standard RS-485 drivers (32 transceivers maximum). Any combination of MAX487E/MAX1487E and other RS-485 transceivers with a total of 32 unit loads or less can be put on the bus. The MAX481E, MAX483E, MAX485E, and MAX488E–MAX491E have standard 12kΩreceiver input impedance.MAX483E/MAX487E/MAX488E/MAX489E:Reduced EMI and Reflections The MAX483E and MAX487E–MAX489E are slew-rate limited, minimizing EMI and reducing reflections caused by improperly terminated cables. F igure 16 shows the driver output waveform and its Fourier analy-sis of a 150kHz signal transmitted by a MAX481E, MAX485E, MAX490E, MAX491E, or MAX1487E. High-frequency harmonics with large amplitudes are evident.F igure 17 shows the same information displayed for a MAX483E, MAX487E, MAX488E, or MAX489E transmit-ting under the same conditions. F igure 17’s high-fre-quency harmonics have much lower amplitudes, and the potential for EMI is significantly reduced.Low-Power Shutdown Mode(MAX481E/MAX483E/MAX487E) 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 0.5µA 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.F or the MAX481E, MAX483E, and MAX487E, the t ZH and t ZL enable times assume the part was not in the low-power shutdown state (the MAX485E, MAX488E–MAX491E, and MAX1487E can not be shut down). The t ZH(SHDN)and t ZL(SHDN)enable times assume the parts were shut down (see Electrical Characteristics).Figure 16. Driver Output Waveform and FFT Plot of MAX485E/MAX490E/MAX491E/MAX1487E Transmitting a 150kHz SignalFigure 17. Driver Output Waveform and FFT Plot ofMAX483E/MAX487E–MAX489E Transmitting a 150kHz SignalMAX481E/MAX483E/MAX485E/ MAX487E–MAX491E/MAX1487E 12±15kV ESD-Protected, Slew-Rate-Limited, Low-Power, RS-485/RS-422 TransceiversIt 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 RE, DE inputs equal a logical 0,1 or 1,1 or 0, 0.)Driver Output Protection Excessive 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 circuits over the whole common-mode voltage range (see Typical Operating Characteristics). In addition, a thermal shut-down circuit forces the driver outputs into a high-imped-ance state if the die temperature rises excessively.Propagation Delay Many digital encoding schemes depend on the differ-ence between the driver and receiver propagation delay times. Typical propagation delays are shown in Figures 19–22 using Figure 18’s test circuit.The difference in receiver delay times, t PLH- t PHL, is typically under 13ns for the MAX481E, MAX485E, MAX490E, MAX491E, and MAX1487E, and is typically less than 100ns for the MAX483E and MAX487E–MAX489E.The driver skew times are typically 5ns (10ns max) for the MAX481E, MAX485E, MAX490E, MAX491E, and MAX1487E, and are typically 100ns (800ns max) for the MAX483E and MAX487E–MAX489E.Typical Applications The MAX481E, MAX483E, MAX485E, MAX487E–MAX491E, and MAX1487E transceivers are designed for bidirectional data communications on multipoint bus transmission lines. F igures 25 and 26 show typical net-work application circuits. These parts can also be used as line repeaters, with cable lengths longer than 4000 feet. 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 MAX483E and MAX487E–MAX489E are more tolerant of imperfect termination. Bypass the V CC pin with 0.1µF.Isolated RS-485 For isolated RS-485 applications, see the MAX253 and MAX1480 data sheets.Line Length vs. Data Rate The RS-485/RS-422 standard covers line lengths up to 4000 feet. Figures 23 and 24 show the system differen-tial voltage for the parts driving 4000 feet of 26AWG twisted-pair wire at 110kHz into 100Ωloads.Figure 18. Receiver Propagation Delay Test Circuit MAX481E/MAX483E/MAX485E/MAX487E–MAX491E/MAX1487E Maxim Integrated13。

MAX3483EESA-T中文资料

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.
元器件交易网
3.3V-Powered, ±15kV ESD-Protected, 12Mbps and Slew-Rate-Limited True RS-485/RS-422 Transceivers
MAX3483E/MAX3485E/MAX3486E/MAX3488E/MAX3490E/MAX3491E
MAX3483E/MAX3485E/MAX3486E/MAX3488E/MAX3490E/MAX3491E
Ordering Information
PART TEMP. RANGE 0°C to +70°C 0°C to +70°C -40°C to +85°C -40°C to +85°C 0°C to +70°C 0°C to +70°C -40°C to +85°C -40°C to +85°C PIN-PACKAGE 8 SO 8 Plastic DIP 8 SO 8 Plastic DIP 8 SO 8 Plastic DIP 8 SO 8 Plastic DIP MAX3483ECSA MAX3483ECPA MAX3483EESA MAX3483EEPA MAX3485ECSA MAX3485ECPA MAX3485EESA MAX3485EEPA

MAX488_全球某工商版中文资料

MAX488By cl1.概述双路单刀双掷无源开关，全双工，0.25Mbps(无源只是转换，有源除了实现232和485转换外还能保证两者之间的电气隔离)VCC，大于等于4.75V，小于等于5.25V，静态电流120uA1.1.RS485RS-485以差动方式发送和接收，两线间电压差为+(2~6)V表示逻辑1，-(2~6)V表示逻辑0，差动工作是同速率条件下传输距离远的根本原因（可达几十米到上千米）；电压比RS232降低了，不易损坏接口电路的芯片，且该电平与TTL电平兼容，方便与TTL电路连接；最高速率10Mbps1.2.RS232RS232-C是EIA(美国电子工业协会Electronic Industry Association)制定的一种串行物理接口标准。

RS是英文“recommended standard(推荐标准)”的缩写，232为标识号，C表示修改次数。

设有25条信号线，包括一个主通道和一个辅助通道。

在多数情况下主要使用主通道，对于一般双工通信，仅需几条信号线就可实现，如一条发送线、一条接收线及一条地线。

RS-232-C标准规定的数据传输速率为每秒50、75、100、150、300、600、1200、2400、4800、9600、19200波特。

RS-232-C标准规定，驱动器允许有2500pF的电容负载，通信距离将受此电容限制；例如，采用150pF/m的通信电缆时，最大通信距离为15m；若每米电缆的电容量减小，通信距离可以增加。

传输距离短的另一原因是RS-232属单端信号传送，存在共地噪声和不能抑制共模干扰等问题，因此一般用于20m以内的通信。

2.封装RO：接收输出(Receiver Output)，当A端电压比B端电压高超过200mV，RO输出高当A端电压比B端电压低200mV以上，RO输出低DI：驱动输入,低电平不能低于-0.5V，高电平不能高于VCC+0.5V 输入低电平时Y输出低，Z输出高；输入高电平时Y输出高，Z输出低3.应用。

MEMORY存储芯片MAX487EESA+T中文规格书

±15kV ESD-Protected, Slew-Rate-Limited,Low-Power, RS-485/RS-422 TransceiversSWITCHING CHARACTERISTICS—MAX483E, MAX487E/MAX488E/MAX489E (V CC = 5V ±5%, T A = T MIN to T MAX , unless otherwise noted.) (Notes 1, 2)SWITCHING CHARACTERISTICS—MAX481E/MAX485E, MAX490E/MAX491E, MAX1487E(continued)(V CC = 5V ±5%, T A = T MIN to T MAX , unless otherwise noted.) (Notes 1, 2)2251000Figures 11 and 13, C L = 100pF, S2 closedFigures 11 and 13, C L = 100pF, S1 closedFigures 9 and 15, C L = 15pF, S2 closed,A -B = 2VCONDITIONSns 45100t ZH(SHDN)Driver Enable from Shutdown to Output High (MAX481E)ns Figures 9 and 15, C L = 15pF, S1 closed,B - A = 2V t ZL(SHDN)Receiver Enable from Shutdown to Output Low (MAX481E)ns 45100t ZL(SHDN)Driver Enable from Shutdown to Output Low (MAX481E)ns 2251000t ZH(SHDN)Receiver Enable from Shutdown to Output High (MAX481E)UNITS MIN TYP MAX SYMBOL PARAMETER t PLH t SKEW Figures 10 and 12, R DIFF = 54Ω,C L1= C L2= 100pF t PHL Figures 10 and 12, R DIFF = 54Ω,C L1= C L2= 100pF Driver Input to OutputDriver Output Skew to Outputns 20800ns ns 2000MAX483E/MAX487E, Figures 11 and 13,C L = 100pF, S2 closed t ZH(SHDN)Driver Enable from Shutdown to Output High 2502000ns 2500MAX483E/MAX487E,Figures 9 and 15,C L = 15pF, S1 closed t ZL(SHDN)Receiver Enable from Shutdownto Output Lowns 2500MAX483E/MAX487E,Figures 9 and 15,C L = 15pF, S2 closed t ZH(SHDN)Receiver Enable from Shutdown to Output High ns 2000MAX483E/MAX487E, Figures 11 and 13,C L = 100pF, S1 closed t ZL(SHDN)Driver Enable from Shutdown to Output Low ns 50200600MAX483E/MAX487E (Note 5) t SHDNTime to Shutdown t PHLt PLH , t PHL < 50% of data period Figures 9 and 15, C RL = 15pF, S2 closed Figures 9 and 15, C RL = 15pF, S1 closed Figures 9 and 15, C RL = 15pF, S2 closed Figures 9 and 15, C RL = 15pF, S1 closed Figures 11 and 13, C L = 15pF, S2 closed Figures 10 and 14, R DIFF = 54Ω,C L1= C L2= 100pF Figures 11 and 13, C L = 15pF, S1 closed Figures 11 and 13, C L = 100pF, S1 closed Figures 11 and 13, C L = 100pF, S2 closed CONDITIONS kbps 250f MAX2508002000Maximum Data Rate ns 2550t HZReceiver Disable Time from High ns 25080020002550t LZReceiver Disable Time from Low ns 2550t ZHReceiver Enable to Output High ns 2550t ZLReceiver Enable to Output Low ns ns 1003003000t HZ t SKDDriver Disable Time from HighI t PLH - t PHL I Differential Receiver Skew Figures 10 and 14, R DIFF = 54Ω,C L1= C L2= 100pF ns 3003000t LZ Driver Disable Time from Lowns 2502000t ZL Driver Enable to Output Lowns Figures 10 and 12, R DIFF = 54Ω,C L1= C L2= 100pF ns 2502000t R , t F 2502000Driver Rise or Fall Timens t PLHReceiver Input to Output 2502000t ZH Driver Enable to Output HighUNITS MIN TYP MAX SYMBOL PARAMETERMAX481E/MAX483E/MAX485E/MAX487E–MAX491E/MAX1487E4±15kV ESD-Protected, Slew-Rate-Limited,Low-Power, RS-485/RS-422 TransceiversFigure 6. IEC1000-4-2 ESD Test ModelFigure 8. Driver DC Test LoadFigure 7. IEC1000-4-2 ESD Generator Current WaveformFigure 9. Receiver Timing Test LoadFigure 4. Human Body ESD Test ModelFigure 5. Human Body Model Current Waveform MAX481E/MAX483E/MAX485E/MAX487E–MAX491E/MAX1487E10。

MAX4823ETP-T中文资料

General DescriptionThe MAX4822–MAX4825 8-channel relay drivers offer built-in kickback protection and drive +3V/+5V non-latching or dual-coil-latching relays. Each independent open-drain output features a 2.7Ω(typ) on-resistance and is guaranteed to sink 70mA (min) of load current.These devices consume less than 300µA (max) quies-cent current and have 1µA output off-leakage current.A Zener-kickback-protection circuit significantly reduces recovery time in applications where switching speed is critical.The MAX4822/MAX4824 feature a unique power-save mode where the relay current, after activation, can be reduced to a level just above the relay hold-current threshold. This mode keeps the relay activated while significantly reducing the power consumption.The MAX4822/MAX4823 feature a 10MH z SPI™-/QSPI™-/MICROWIRE™-compatible serial interface.Input data is shifted into a shift register and latched to the outputs when CS transitions from low to high. Each data bit in the shift register corresponds to a specific output, allowing independent control of all outputs. The MAX4824/MAX4825 feature a 4-bit parallel-input interface. The first 3 bits (A0, A1, A2) determine the out-put address, and the fourth bit (LVL) determines whether the selected output is switched on or off. Data is latched to the outputs when CS transitions from low to high.The MAX4822–MAX4825 feature separate set and reset functions, allowing turn-on or turn-off of all outputs simultaneously with a single control line. Built-in hys-teresis (Schmidt trigger) on all digital inputs allows these devices to be used with slow-rising and falling signals, such as those from optocouplers or RC power-up initialization circuits. The MAX4822–MAX4825 are available in space-saving 4mm x 4mm, 20-pin thin QFN packages. They are specified over the -40°C to +85°C extended temperature range.ApplicationsATE EquipmentDSL Redundancy Protection (ADSL/VDSL/HDSL)T1/E1 Redundancy Protection T3/E3 Redundancy Protection Industrial EquipmentTest Equipment (Oscilloscopes, Spectrum Analyzers)Features♦Built-In Zener Kickback Protection for Fast Recovery ♦Programmable Power-Save Mode Reduces Relay Power Consumption (MAX4822/MAX4824)♦10MHz SPI-/QSPI-/MICROWIRE-Compatible Serial Interface ♦Eight Independent Output Channels ♦Drive +3V and +5V Relays♦Guaranteed 70mA (min) Coil Drive Current ♦Guaranteed 5Ω(max) R ON♦SET / RESET Functions to Turn On/Off All Outputs Simultaneously ♦Serial Digital Output for Daisy Chaining ♦Optional Parallel Interface (MAX4824/MAX4825)♦Low 300µA (max) Quiescent Supply Current ♦Space-Saving, 4mm x 4mm, 20-Pin TQFN PackageMAX4822–MAX4825+3.3V/+5V , 8-Channel Relay Drivers with FastRecovery Time and Power-Save Mode________________________________________________________________Maxim Integrated Products1Ordering Information19-3789; Rev 0; 8/05For pricing, delivery, and ordering information,please contact Maxim/Dallas Direct!at 1-888-629-4642, or visit Maxim’s website at .*For maximum heat dissipation, packages have an exposed pad (EP) on the bottom. Solder exposed pad to GND.SPI is a trademark of Motorola, Inc.QSPI is a trademark of Motorola, Inc.MICROWIRE is a trademark of National Semiconductor Corp.M A X 4822–M A X 4825+3.3V/+5V , 8-Channel Relay Drivers with Fast Recovery Time and Power-Save Mode 2_______________________________________________________________________________________ABSOLUTE MAXIMUM RATINGSStresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.V CC ........................................................................-0.3V to +6.0V OUT_......................................................................-0.3V to +11V CS , SCLK, DIN, SET , RESET , A0, A1, A2, LVL......-0.3V to +6.0V DOUT..........................................................-0.3V to (V CC + 0.3V)PSAVE........................................................-0.3V to (V CC + 0.3V)Continuous OUT_ Current (all outputs turned on)............150mA Continuous OUT_ Current (single output turned on)........300mAContinuous Power Dissipation (T A = +70°C)20-Lead Thin QFN (derate 16.9mW/°C above +70°C)..1350mW Operating Temperature Range ...........................-40°C to +85°C Junction Temperature......................................................+150°C Storage Temperature Range.............................-65°C to +150°C Soldering Temperature (10s)...........................................+300°CELECTRICAL CHARACTERISTICSMAX4822–MAX4825+3.3V/+5V , 8-Channel Relay Drivers with FastRecovery Time and Power-Save Mode_______________________________________________________________________________________3ELECTRICAL CHARACTERISTICS (continued)M A X 4822–M A X 4825+3.3V/+5V , 8-Channel Relay Drivers with Fast Recovery Time and Power-Save Mode 4_______________________________________________________________________________________Note 4:The circuit can set the output voltage in power-save mode only if I OUT x R ON < V OUTP .Note 5:After relay turn-off, inductive kickback can momentarily cause the OUT_ voltage to exceed V CC . This is considered part of normal operation and does not damage the device.Note 6:Guaranteed by design.Note 7:For other capacitance values, use the equation t PS = 32 x C.ELECTRICAL CHARACTERISTICS (continued)(V CC = +2.7V to +5.5V, T A = -40°C to +85°C, unless otherwise noted. Typical values are at V CC = 2.7V, T A = +25°C, unless otherwise noted.) (Note 1)MAX4822–MAX4825+3.3V/+5V , 8-Channel Relay Drivers with FastRecovery Time and Power-Save Mode_______________________________________________________________________________________5QUIESCENT SUPPLY CURRENTvs. SUPPLY VOLTAGESUPPLY VOLTAGE (V)S U P P L Y C U R R E N T (µA )5.14.72.73.13.53.94.31451501551601651701751801402.35.5QUIESCENT SUPPLY CURRENTvs. TEMPERATURETEMPERATURE (°C)S U P P L Y C U R R E N T (µA )603510-15110120130140150160170180190200100-40850.200.600.401.201.000.801.601.801.402.0014523678910DYNAMIC SUPPLY CURRENTvs. FREQUENCYFREQUENCY (MHz)D Y N A M I C S U P P L Y C U R RE N T (m A )QUIESCENT SUPPLY CURRENT vs. LOGIC-INPUT VOLTAGELOGIC-INPUT VOLTAGE (V)S U P P L Y C U R R E N T (µA )432110020030040050060070080090010001100005ON-RESISTANCE vs. SUPPLY VOLTAGESUPPLY VOLTAGE (V)R O N (Ω)5.14.72.73.13.53.94.31.752.002.252.502.753.003.253.501.502.35.5ON-RESISTANCE vs. TEMPERATURETEMPERATURE (°C)R O N (Ω)603510-152.02.53.03.54.01.5-4085POWER-ON RESET VOLTAGEvs. TEMPERATUREM A X 4822-25 t o c 07TEMPERATURE (°C)P O W E R -O N R E S E T V O L T A G E (V )603510-151.051.101.151.201.251.301.351.401.451.501.551.601.651.701.00-4085OUTPUT OFF-LEAKAGE CURRENTvs. SUPPLY VOLTAGEM A X 4822-25 t o c 08SUPPLY VOLTAGE (V)O U T P U T O F F -L E A K A G E (pA )5.14.74.33.93.53.12.712345602.3 5.5OUTPUT OFF-LEAKAGE CURRENTvs. TEMPERATURETEMPERATURE (°C)O U T P U T O F F -L E A K A G E (n A )603510-150.010.11100.001-4085Typical Operating Characteristics(V CC = 3.3V, T A = +25°C, unless otherwise noted.)M A X 4822–M A X 4825+3.3V/+5V , 8-Channel Relay Drivers with Fast Recovery Time and Power-Save Mode 6_______________________________________________________________________________________OUT_ TURN-ON DELAY TIME vs. SUPPLY VOLTAGEM A X 4822-25 t o c 10SUPPLY VOLTAGE (V)I O N D E L A Y T I M E (n s )5.14.74.33.93.53.12.7406080100120140202.35.5OUT_ TURN-OFF DELAY TIMEvs. SUPPLY VOLTAGEM A X 4822-25 t o c 11SUPPLY VOLTAGE (V)I O F F D E L A Y T I M E (n s ) 5.14.74.33.93.53.12.760080010001200140016004002.3 5.5INPUT-LOGIC THRESHOLD vs. SUPPLY VOLTAGEM A X 4822-25 t o c 2SUPPLY VOLTAGE (V)I N P U T -L O G I C T H R E S H O L D (V )5.14.73.9 4.33.1 3.52.71.11.21.31.41.51.61.71.81.92.02.11.02.3 5.5BACK EMF CLAMPING WITH STANDARD 3V RELAY V CC = 3.3V MAX4822-25 toc13100µs/div0V0VCS 5V/divVOUT 2V/divPOWER-SAVE DELAY TIMEvs. CAPACITANCECAPACITANCE (nF)t P S (m s )800600200400510152030253540001000POWER-SAVE DELAY TIME vs. SUPPLY VOLTAGESUPPLY VOLTAGE (V)t P S (m s )5.14.73.94.33.13.52.73.553.603.653.703.753.803.853.903.954.003.502.35.50.30.40.60.50.70.810050150200250300OUTPUT VOLTAGE vs. OUTPUT CURRENTIN POWER-SAVE MODE (PSAVE REGISTER = 111)M A X 4822 t o c 16OUTPUT CURRENT (mA)O U T P U T V O L T A G E (V )Typical Operating Characteristics (continued)(V CC = 3.3V, T A = +25°C, unless otherwise noted.)MAX4822–MAX4825+3.3V/+5V , 8-Channel Relay Drivers with FastRecovery Time and Power-Save Mode_______________________________________________________________________________________7MAX4822/MAX4823 Pin DescriptionM A X 4822–M A X 4825+3.3V/+5V , 8-Channel Relay Drivers with Fast Recovery Time and Power-Save Mode 8_______________________________________________________________________________________MAX4822/MAX4823 Pin Description (continued)MAX4824/MAX4825 Pin DescriptionDetailed DescriptionSerial Interface (MAX4822/MAX4823)Depending on the MAX4822/MAX4823 device, the serial interface can be controlled by either 8- or 16-bit words as depicted in Figures 1 and 2. The MAX4823 does not support power-save mode, so the serial interface con-sists of an 8-bit-only shift register for faster control.The MAX4822 consists of a 16-bit shift register and par-allel latch controlled by SCLK and CS . The input to the shift register is a 16-bit word. In the MAX4822, the first 8 bits determine the register address and are followedsponds to the MSB of the 8-bit register address in Figure 1, while bit D7 corresponds to the MSB of the 8bits of data in the same Figure 1.The MAX4823 consists of an 8-bit shift register and par-allel latch controlled by SCLK and CS . The input to the shift register is an 8-bit word. Each data bit controls one of the eight outputs, with the most significant bit (D7) corresponding to OUT8, and the least significant bit (D0) corresponding to OUT1 (see Figure 2).MAX4822–MAX4825+3.3V/+5V , 8-Channel Relay Drivers with FastRecovery Time and Power-Save Mode_______________________________________________________________________________________9M A X 4822–M A X 4825When CS is low (MAX4822/MAX4823 device is select-ed), data at DIN is clocked into the shift register syn-chronously with SCLK’s rising edge. Driving CS from low to high latches the data in the shift register (Figures 5 and 6).DOUT is the output of the shift register. Data appears on DOUT synchronously with SCLK’s falling edge and is identical to the data at DIN delayed by eight clock cycles for the MAX4823, or 16 clock cycles for the MAX4822. When shifting the input data, A7 is the first input bit in and out of the shift register for the MAX4822device. D7 is the first bit in or out of the shift register for+3.3V/+5V , 8-Channel Relay Drivers with Fast Recovery Time and Power-Save Mode 10______________________________________________________________________________________Figure 1. 16-Bit Register Map for MAX4822the MAX4823 device. If the address A0…….A7 is not 00h or 01h, then the outputs and the PSAVE configura-tion register are not updated. The address is stored in the shift register only.While CS is low, the OUT_ outputs always remain in their previous state. For the MAX4823, drive CS high after 8bits of data have been shifted in to update the output state of the MAX4823, and to further inhibit data from entering the shift register. For the MAX4822, drive CS high after 16 bits of data have been shifted in to update the output state of the MAX4822, and to further inhibit data from entering the shift register. When CS is high, transi-tions at DIN and SCLK have no effect on the output, and the first input bit A7 (or D7) is present at DOUT.For the MAX4822, if the number of data bits entered while CS is low is greater or less than 16, the shift regis-ter contains only the last 16 bits, regardless of when they were entered. For the MAX4823, if the number of data bits entered while CS is low is greater or less than 8, the shift register contains only the last 8 data bits,regardless of when they were entered.Parallel Interface (MAX4824/MAX4825)The parallel interface consists of 3 address bits (A0,A1, A2) and one level selector bit (LVL). The address bits determine which output is updated, and the level bit determines whether the addressed output is switched on (LVL = high) or off (LVL = low). When CS is high, the address and level bits have no effect on the state of the outputs. Driving CS from low to high latchesMAX4822–MAX4825Recovery Time and Power-Save Mode______________________________________________________________________________________11Figure 4. 3-Wire Serial-Interface Timing DiagramFigure 2. 8-Bit Register Map for MAX4823M A X 4822–M A X 4825level data to the parallel register and updates the state of the outputs. Address data entered after CS is pulled low is not reflected in the state of the outputs following the next low-to-high transition on CS (Figure 7).SET/RESET FunctionsThe MAX4822–MAX4825 feature set and reset inputs that allow simultaneous turn-on or turn-off of all outputs using a single control line. Drive SET low to set all latch-es and registers to 1 and turn all outputs on. SET over-rides all serial/parallel control inputs. Drive RESET low to clear all latches and registers and to turn all outputs off. RESET overrides all other inputs including SET .Power-On ResetThe MAX4822–MAX4825 feature power-on reset. The power-on reset function causes all latches to be cleared automatically upon power-up. This ensures that all outputs come up in the off or high-impedance state.Applications InformationDaisy ChainingThe MAX4822/MAX4823 feature a digital output (DOUT) that provides a simple way to daisy chain multi-ple devices. This feature allows driving large banks of relays using only a single serial interface. To daisy chain multiple devices, connect all CS inputs together,and connect the DOUT of one device to the DIN of another device (see Figure 8). During operation, a stream of serial data is shifted through the MAX4822/MAX4823 devices in series. When CS goes high, all outputs update simultaneously.The MAX4822/MAX4823 can also be used in a slave configuration that allows individual addressing of devices. Connect all the DIN inputs together, and usethe CS input to address one device at a time. Drive CS low to select a slave and input the data into the shift register. Drive CS high to latch the data and turn on the appropriate outputs. Typically, in this configuration only one slave is addressed at a time.Power-Save ModeThe MAX4822/MAX4824 feature a unique power-save mode where the relay current, after activation, can be reduced to a level just above the relay hold-current threshold. This mode keeps the relay activated while significantly reducing the power consumption.In serial mode (MAX4822), choose between seven cur-rent levels ranging from 30% to 90% of the nominal cur-rent in 10% increments. The actual percentage is determined by the power-save configuration register (Figure 1).In parallel mode (MAX4824), the power-save current is fixed at 60% of the nominal current.Power-Save TimerEvery time there is a write operation to the device (CS transitions from low to high), the MAX4822/MAX4824start charging the capacitor connected to PSAVE. The serial power-save implementation is such that a write operation does not change the state of channels already in power-save mode (unless the write turns the channel OFF).After a certain time period, t PS (determined by the capacitor value), the capacitor reaches a voltage threshold that sets all active outputs to power-save mode. The t PS period should be made long enough to allow the relay to turn on completely. The time period t PS can be adjusted by using different capacitor valuesRecovery Time and Power-Save Mode 12______________________________________________________________________________________Figure 5. 3-Wire Serial-Interface Operation for MAX4822connected to PSAVE. The value t PS is given by the fol-lowing formula:t PS = 32 x Cwhere C is in µF and t PS is in ms.For example, if the desired t PS is 20ms, then the required capacitor value is 20 / 32 = 0.625µF.Power-Save Mode AccuracyThe current through the relay is controlled by setting the voltage at OUT_ to a percentage of the V CC supply as specified under the Electrical Characteristics and in the register description. The current through the relay (I OUT )depends on the switch on-resistance, R ON,in addition to the relay resistance R R according to the fol-lowing relation:I OUT = V CC / (R ON + R R )The power-save, current-setting I PS depends on the fraction αof the supply voltage V CC that is set by the loop depending on the following relation:I PS = V CC - (αx V CC ) / R RTherefore:I PS / I OUT = (1- α) x (1 + R ON / R R )This relation shows how the fraction of reduction in the current depends on the switch on-resistance, as well as from the accuracy of the voltage setting (α). The higher the R ON with respect to R R, the higher the inaccuracy.This is particularly true at low voltage when the relay resistance is low (less than 40Ω) and the switch can account for up to 10% of the total resistance. In addi-tion, when the supply-voltage setting (α) is low (10% or 20%) and the supply voltage (V CC ) is low, the voltage drop across the switch (I OUT x R ON ) may already exceed, or may be very close to, the desired voltage-setting value.Daisy Chaining and Power-Save ModeIn a normal configuration using the power-save feature,several MAX4822s can be daisy chained as shown in Figure 9. For each MAX4822, the power-save timing t PD (time it takes to reduce the relay current once the relay is actuated) is controlled by the capacitor con-nected to PSAVE.An alternative configuration that eliminates the PSAVE capacitors uses a common PSAVE control line driven by an open-drain n-channel MOSFET (Figure 10). In this con-figuration, the PSAVE inputs are connected together to asynchronously control the power-save timing for all the MAX4822s in the chain. The µC/µP drives the n-channel MOSFET low for the duration of a write cycle to the SPI chain, plus some delay time to allow the relays to close.(This time is typically specified in the relay data sheet.)Once this delay time has elapsed, the n-channel MOSFET is turned off, allowing the MAX4822’s internal 35µA pullup current to raise PSAVE to a logic-high level, activating the power-save mode in all active outputs.MOSFET SelectionIn the daisy-chain configuration of Figure 10, the n-channel MOSFET drives PSAVE low. When the n-channel MOSFET is turned off, PSAVE is pulled high by an internal 35µA pullup in each MAX4822, and the power-save mode is enabled. Because of the paralleled PSAVE pullup currents, the required size of the n-channel MOSFET depends upon the number of MAX4822 devices in the chain. Determine the size of the n-channel MOSFET by the following relation:R ON < 1428 / NMAX4822–MAX4825Recovery Time and Power-Save Mode______________________________________________________________________________________13Figure 6. 3-Wire Serial-Interface Operation for the MAX4823Figure 7. Parallel-Interface Timing DiagramM A X 4822–M A X 4825where N is the total number of MAX4822 devices in a single chain, and R ON is the on-resistance of the n-channel MOSFET in Ωs.For example, if N = 10:R ON < 142ΩAn n-channel MOSFET with R ON less than 142Ωis required for a daisy chain of 10 MAX4822 devices.Inductive Kickback Protection withFast Recovery TimeThe MAX4822–MAX4825 feature built-in inductive kick-back protection to reduce the voltage spike on OUT_generated by a relay’s coil inductance when the output is suddenly switched off. An internal Zener clamp allows the inductor current to flow back to ground. The Zener configuration significantly reduces the recovery time (time it takes to turn off the relay) when compared to protection configurations with just one diode across the coil.Recovery Time and Power-Save Mode 14______________________________________________________________________________________Figure 9. Daisy-Chained MAX4822s with a Capacitor Connected to PSAVEFigure 8. Daisy-Chain ConfigurationMAX4822–MAX4825Recovery Time and Power-Save Mode______________________________________________________________________________________15Figure 10. Daisy-Chaining MAX4822s with a PSAVE Connected to an n-Channel MOSFETChip InformationTRANSISTOR COUNT: 5799PROCESS: BiCMOSM A X 4822–M A X 4825Recovery Time and Power-Save Mode 16______________________________________________________________________________________MAX4822/MAX4823 Functional Diagram (Serial Interface)MAX4822–MAX4825Recovery Time and Power-Save Mode______________________________________________________________________________________17MAX4824/MAX4825 Functional Diagram (Parallel Interface)M A X 4822–M A X 4825Recovery Time and Power-Save Mode 18______________________________________________________________________________________Pin ConfigurationsRecovery Time and Power-Save Mode Maxim 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©2005 Maxim Integrated Products Printed USAis a registered trademark of Maxim Integrated Products, Inc.MAX4822–MAX4825Package 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.)。

MAX487中文资料_引脚功能图_参数

美国MAXIM公司生产的MAX487E型器件为主要电路的新型光电隔离型接口转换器。

它兼容RS-232C、RS-422和RS-485标准,可以实现单端RS-232和差分RS-422/485信号之间的相互转换,并可比较有效地防止雷击和共地干扰。

该转换器电路的设计新颖,工作可靠, 成本低廉,可以满足恶劣环境下的现场控制和数据采集场合的使用要求。

MAX487-MAX491以及MAX1487是用于baiRS-485与RS-422通信的低功耗收发器，du每个器件中都具有一个驱动器和一zhi个接收器。

MAX483、MAX487、MAX488以及daoMAX489具有限摆率驱动器，可以减小EMI，并降低由不恰当的终端匹配电缆引起的反射，实现最高250kbps的无差错数据传输。

MAX481、MAX485、MAX490、MAX491、MAX1487的驱动器摆率不受限制，可以实现最高2.5Mbps的传输速率。

这些收发器在驱动器禁用的空载或满载状态下，吸取的电源电流在120μA至500μA之间。

另外，MAX481、MAX483与MAX487具有低电流关断模式，仅消耗0.1μA。

所有器件都工作在5V单电源下。

驱动器具有短路电流限制，并可以通过热关断电路将驱动器输出置为高阻状态，防止过度的功率损耗。

接收器输入具有失效保护特性，当输入开路时，可以确保逻辑高电平输出。

MAX487与MAX1487具有1/4单位负载的接收器输入阻抗，使得总线上最多可以有128个MAX487/MAX1487收发器。

使用MAX488-MAX491可以实现全双工通信，而MAX481、MAX483、MAX485、MAX487与MAX1487则为半双工应用设计。

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MAX481ESA+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 .)。