MAX3070EASD中文资料

General DescriptionThe MAX481E, MAX483E, MAX485E, MAX487E–MAX491E, and MAX1487E are low-power transceivers for RS-485 and RS-422 communications in harsh environ-ments. Each driver output and receiver input is protected against ±15kV electro-static discharge (ESD) shocks,without latchup. These parts contain one driver and one receiver. The MAX483E, MAX487E, MAX488E, and MAX489E feature reduced slew-rate drivers that minimize EMI and reduce reflections caused by improperly termi-nated cables, thus allowing error-free data transmission up to 250kbps. The driver slew rates of the MAX481E,MAX485E, MAX490E, MAX491E, and MAX1487E are not limited, allowing them to transmit up to 2.5Mbps.These transceivers draw as little as 120µA supply cur-rent when unloaded or when fully loaded with disabled drivers (see Selector Guide ). Additionally, the MAX481E,MAX483E, and MAX487E have a low-current shutdown mode in which they consume only 0.5µA. All parts oper-ate from a single +5V supply.Drivers are short-circuit current limited, and are protected against excessive power dissipation by thermal shutdown circuitry that places their outputs into a high-impedance state. The receiver input has a fail-safe feature that guar-antees a logic-high output if the input is open circuit.The MAX487E and MAX1487E feature quarter-unit-load receiver input impedance, allowing up to 128 trans-ceivers 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 pin-and function-compatible MAX481, MAX483, MAX485,MAX487–MAX491, and MAX1487.ApplicationsLow-Power RS-485 Transceivers Low-Power RS-422 Transceivers Level TranslatorsTransceivers for EMI-Sensitive Applications Industrial-Control Local Area NetworksNext-Generation Device Features♦For Fault-Tolerant Applications:MAX3430: ±80V Fault-Protected, Fail-Safe, 1/4-Unit Load, +3.3V, RS-485 TransceiverMAX3080–MAX3089: Fail-Safe, High-Speed (10Mbps), Slew-Rate-Limited, RS-485/RS-422Transceivers ♦For Space-Constrained Applications:MAX3460–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-422True Fail-Safe ReceiversMAX3030E–MAX3033E: ±15kV ESD-Protected,+3.3V, Quad RS-422 Transmitters ♦For Multiple Transceiver Applications:MAX3293/MAX3294/MAX3295: 20Mbps, +3.3V,SOT23, RS-485/RS-422 Transmitters ♦For Fail-Safe Applications:MAX3440E–MAX3444E: ±15kV ESD-Protected,±60V Fault-Protected, 10Mbps, Fail-Safe RS-485/J1708 Transceivers ♦For Low-Voltage Applications:MAX3483E/MAX3485E/MAX3486E/MAX3488E/MAX3490E/MAX3491E: +3.3V Powered, ±15kV ESD-Protected, 12Mbps, Slew-Rate-Limited, True RS-485/RS-422 TransceiversMAX481E/MAX483E/MAX485E/MAX487E–MAX491E/MAX1487E±15kV ESD-Protected, Slew-Rate-Limited, Low-Power, RS-485/RS-422 Transceivers________________________________________________________________Maxim Integrated Products 1Ordering Information19-0410; Rev 4; 10/03For pricing, delivery, and ordering information,please contact Maxim/Dallas Direct!at 1-888-629-4642, or visit Maxim’s website at .Ordering Information continued at end of data sheet.Selector Guide appears at end of data sheet .M A X 481E /M A X 483E /M A X 485E /M A X 487E –M A X 491E /M A X 1487E±15kV ESD-Protected, Slew-Rate-Limited,Low-Power, RS-485/RS-422 Transceivers2_______________________________________________________________________________________Supply Voltage (V CC ) (12V)Control Input Voltage (–R —E –, DE)...................-0.5V to (V CC + 0.5V)Driver Input Voltage (DI).............................-0.5V to (V CC + 0.5V)Driver Output Voltage (Y, Z; 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)....727mW14-Pin Plastic DIP (derate 10.00mW/°C above +70°C)..800mW 8-Pin SO (derate 5.88mW/°C above +70°C).................471mW 14-Pin SO (derate 8.33mW/°C above +70°C)...............667mW Operating Temperature RangesMAX4_ _C_ _/MAX1487EC_ A.............................0°C to +70°C MAX4__E_ _/MAX1487EE_ A...........................-40°C to +85°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.ABSOLUTE MAXIMUM RATINGSPARAMETERSYMBOL MINTYPMAX UNITS Driver Common-Mode Output VoltageV OC 3V Change in Magnitude of Driver Differential Output Voltage for Complementary Output States ∆V OD 0.2V Change in Magnitude of Driver Common-Mode Output Voltage for Complementary Output States ∆V OD 0.2V Input High Voltage V IH 2.0V Input Low Voltage V IL 0.8V Input CurrentI IN1±2µADifferential Driver Output (no load)V OD15V 2V Differential Driver Output (with load)V OD2 1.551.0-0.8mA0.25mA -0.2Receiver Differential Threshold Voltage-0.20.2V Receiver Input Hysteresis ∆V TH 70mV Receiver Output High Voltage V OH 3.5Receiver Output Low Voltage V OL 0.4V Three-State (high impedance)Output Current at ReceiverI OZR±1µA 12k ΩCONDITIONSDE = 0V;V CC = 0V or 5.25V,all devices except MAX487E/MAX1487E R = 27Ωor 50Ω, Figure 8R = 27Ωor 50Ω, Figure 8R = 27Ωor 50Ω, Figure 8DE, DI, –R —E–MAX487E/MAX1487E,DE = 0V, V CC = 0V or 5.25VDE, DI, –R —E–DE, DI, –R —E–-7V ≤V CM ≤12V V CM = 0VI O = -4mA, V ID = 200mV I O = 4mA, V ID = -200mV R = 50Ω(RS-422)0.4V ≤V O ≤2.4VR = 27Ω(RS-485), Figure 8-7V ≤V CM ≤12V, all devices except MAX487E/MAX1487EReceiver Input Resistance R IN-7V ≤V CM ≤12V, MAX487E/MAX1487E48k ΩV TH I IN2Input Current (A, B)V IN = 12V V IN = -7V V IN = 12V V IN = -7VVMAX481E/MAX483E/MAX485E/MAX487E–MAX491E/MAX1487E±15kV ESD-Protected, Slew-Rate-Limited,Low-Power, RS-485/RS-422 TransceiversSWITCHING CHARACTERISTICS—MAX481E/MAX485E, MAX490E/MAX491E, MAX1487EDC ELECTRICAL CHARACTERISTICS (continued)(V CC = 5V ±5%, T A = T MIN to T MAX , unless otherwise noted.) (Notes 1, 2)M A X 481E /M A X 483E /M A X 485E /M A X 487E –M A X 491E /M A X 1487E±15kV ESD-Protected, Slew-Rate-Limited,Low-Power, RS-485/RS-422 Transceivers4_______________________________________________________________________________________SWITCHING 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 closed Figures 11 and 13, C L = 100pF, S1 closed Figures 9 and 15, C L = 15pF, S2 closed,A - B = 2VCONDITIONSns 45100t ZH(SHDN)Driver Enable from Shutdown toOutput High (MAX481E)nsFigures 9 and 15, C L = 15pF, S1 closed,B - A = 2Vt ZL(SHDN)Receiver Enable from Shutdownto Output Low (MAX481E)ns 45100t ZL(SHDN)Driver Enable from Shutdown toOutput Low (MAX481E)ns 2251000t ZH(SHDN)Receiver Enable from Shutdownto Output High (MAX481E)UNITS MINTYP MAX SYMBOLPARAMETERt PLH t SKEW Figures 10 and 12, R DIFF = 54Ω,C L1= C L2= 100pFt PHL Figures 10 and 12, R DIFF = 54Ω,C L1= C L2= 100pFDriver Input to Output Driver Output Skew to Output ns 20800ns ns 2000MAX483E/MAX487E, Figures 11 and 13,C L = 100pF, S2 closedt ZH(SHDN)Driver Enable from Shutdown to Output High2502000ns2500MAX483E/MAX487E, Figures 9 and 15,C L = 15pF, S1 closedt ZL(SHDN)Receiver Enable from Shutdown to Output Lowns 2500MAX483E/MAX487E, Figures 9 and 15,C L = 15pF, S2 closedt ZH(SHDN)Receiver Enable from Shutdown to Output Highns 2000MAX483E/MAX487E, Figures 11 and 13,C L = 100pF, S1 closedt ZL(SHDN)Driver Enable from Shutdown to Output Lowns 50200600MAX483E/MAX487E (Note 5)t SHDN Time to Shutdownt PHL t 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= 100pFFigures 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 CONDITIONSkbps 250f MAX 2508002000Maximum Data Rate ns 2550t HZ Receiver Disable Time from High ns 25080020002550t LZ Receiver Disable Time from Low ns 2550t ZH Receiver Enable to Output High ns 2550t 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 10 and 14, 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 10 and 12, 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 PARAMETERMAX481E/MAX483E/MAX485E/MAX487E–MAX491E/MAX1487E±15kV ESD-Protected, Slew-Rate-Limited,Low-Power, RS-485/RS-422 Transceivers_______________________________________________________________________________________505101520253035404550OUTPUT CURRENT vs.RECEIVER OUTPUT LOW VOLTAGEM A X 481E -01OUTPUT LOW VOLTAGE (V)O U T P U T C U R R E N T (m A )1.52.02.51.00.50.10.20.30.40.50.60.70.80.9-60-2060RECEIVER OUTPUT LOW VOLTAGEvs. TEMPERATURETEMPERATURE (°C)O U T P U T L O W V O L T A G E (V )20100-4040800-5-10-15-20-251.53.0OUTPUT CURRENT vs.RECEIVER OUTPUT HIGH VOLTAGEM A X 481E -02OUTPUT HIGH VOLTAGE (V)O U T P U T C U R R E N T (m A )5.04.54.02.02.53.53.03.23.43.63.84.04.24.44.64.8-60-2060RECEIVER OUTPUT HIGH VOLTAGEvs. TEMPERATURETEMPERATURE (°C)O U T P U T H I G H V O L T A G E (V )20100-4040800102030405060708090DRIVER OUTPUT CURRENT vs. DIFFERENTIAL OUTPUT VOLTAGEM A X 481E -05DIFFERENTIAL OUTPUT VOLTAGE (V)O U T P U T C U R R E N T (m A )1.52.0 2.53.0 3.54.0 4.51.00.50__________________________________________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 MAX481E/MAX483E/MAX487E are put into shutdown by bringing –R —E –high and DE low. If the inputs are in this state forless than 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 481E /M A X 483E /M A X 485E /M A X 487E –M A X 491E /M A X 1487E±15kV ESD-Protected, Slew-Rate-Limited,Low-Power, RS-485/RS-422 Transceivers6___________________________________________________________________________________________________________________Typical Operating Characteristics (continued)(V CC = 5V, T A = +25°C, unless otherwise noted.)1.52.32.22.12.01.91.81.71.6-60-2060DRIVER DIFFERENTIAL OUTPUT VOLTAGE vs. TEMPERATURETEMPERATURE (°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 )20100-404080020406080100120140OUTPUT CURRENT vs. DRIVER OUTPUT LOW VOLTAGEM A X 481E -07OUTPUT LOW VOLTAGE (V)O U T P U T C U R R E N T (m A )246810120-10-20-30-40-50-60-70-80-90-100-8-2OUTPUT CURRENT vs. DRIVER OUTPUT HIGH VOLTAGEM A X 481E -08OUTPUT HIGH VOLTAGE (V)O U T P U T C U R R E N T (m A )642-6-400100200300400500600-60-2060MAX481E/MAX485E/MAX490E/MAX491E SUPPLY CURRENT vs. TEMPERATURETEMPERATURE (°C)S U P P L Y C U R R E N T (µA )20100-4040800100200300400500600-60-2060MAX483E/MAX487E–MAX489E SUPPLY CURRENT vs. TEMPERATURETEMPERATURE (°C)S U P P L Y C U R R E N T (µA )20100-404080100200300400500600-60-2060MAX1487ESUPPLY CURRENT vs. TEMPERATURETEMPERATURE (°C)S U P P L Y C U R R E N T (µA )20100-404080±15kV ESD-Protected, Slew-Rate-Limited, Low-Power, RS-485/RS-422 Transceivers_______________________________________________________________________________________7MAX481E/MAX483E/MAX485E/MAX487E–MAX491E/MAX1487E______________________________________________________________Pin DescriptionM A X 481E /M A X 483E /M A X 485E /M A X 487E –M A X 491E /M A X 1487E±15kV ESD-Protected, Slew-Rate-Limited,Low-Power, RS-485/RS-422 Transceivers8_________________________________________________________________________________________________Function Tables (MAX481E/MAX483E/MAX485E/MAX487E/MAX1487E) Table 1. Transmitting__________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 Figure 4 shows the Human Body Model, and Figure 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±15kV ESD-Protected, Slew-Rate-Limited,Low-Power, RS-485/RS-422 Transceivers_______________________________________________________________________________________9M A X 481E /M A X 483E /M A X 485E /M A X 487E –M A X 491E /M A X 1487E±15kV ESD-Protected, Slew-Rate-Limited,Low-Power, RS-485/RS-422 Transceivers10______________________________________________________________________________________Figure 8. Driver DC Test LoadFigure 9. Receiver Timing Test LoadMAX481E/MAX483E/MAX485E/MAX487E–MAX491E/MAX1487E±15kV ESD-Protected, Slew-Rate-Limited,Low-Power, RS-485/RS-422 Transceivers______________________________________________________________________________________11Figure 10. Driver/Receiver Timing Test Circuit Figure 11. Driver Timing Test LoadFigure 12. Driver Propagation DelaysFigure 13. Driver Enable and Disable Times (except MAX488E and MAX490E)Figure 14. Receiver Propagation DelaysFigure 15. Receiver Enable and Disable Times (except MAX488E and MAX490E)M A X 481E /M A X 483E /M A X 485E /M A X 487E –M A X 491E /M A X 1487E±15kV ESD-Protected, Slew-Rate-Limited,Low-Power, RS-485/RS-422 Transceivers12______________________________________________________________________________________The 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 ModelThe 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 BusThe 48k Ω, 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 (12k Ωinput 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 12k Ωreceiver 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. Figure 16shows 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.Figure 17 shows the same information displayed for a MAX483E, MAX487E, MAX488E, or MAX489E transmit-ting under the same conditions. Figure 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.For 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 ).500kHz/div0Hz5MHz 10dB/div Figure 16. Driver Output Waveform and FFT Plot ofMAX485E/MAX490E/MAX491E/MAX1487E Transmitting a 150kHz Signal500kHz/div0Hz5MHz10dB/divFigure 17. Driver Output Waveform and FFT Plot ofMAX483E/MAX487E–MAX489E Transmitting a 150kHz SignalIt 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. Figures 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 CircuitMAX481E/MAX483E/MAX485E/MAX487E–MAX491E/MAX1487E±15kV ESD-Protected, Slew-Rate-Limited,Low-Power, RS-485/RS-422 Transceivers ______________________________________________________________________________________13M A X 481E /M A X 483E /M A X 485E /M A X 487E –M A X 491E /M A X 1487E±15kV ESD-Protected, Slew-Rate-Limited,Low-Power, RS-485/RS-422 Transceivers14______________________________________________________________________________________25ns/div 5V/divRO B A500mV/div Figure 19. MAX481E/MAX485E/MAX490E/MAX1487E Receiver t PHL25ns/div5V/div ROBA500mV/divFigure 20. MAX481E/MAX485E/MAX490E/MAX491E/MAX1487E Receiver t PLH200ns/div 5V/divRO B A500mV/div Figure 21. MAX483E/MAX487E–MAX489E Receiver t PHL200ns/div5V/div ROBA500mV/divFigure 22. MAX483E/MAX487E–MAX489E Receiver t PLH2µs/div DO 0V0V5V5V -1V 0DIV A - V BFigure 23. MAX481E/MAX485E/MAX490E/MAX491E/MAX1487E System Differential Voltage at 110kHz Driving 4000ft of Cable 2µs/divDO0V0V 5V 5V -1V1V0DIV B - V AFigure 24. MAX483E/MAX1487E–MAX489E System Differential Voltage at 110kHz Driving 4000ft of CableMAX481E/MAX483E/MAX485E/MAX487E–MAX491E/MAX1487E±15kV ESD-Protected, Slew-Rate-Limited,Low-Power, RS-485/RS-422 Transceivers______________________________________________________________________________________15Figure 26. MAX488E–MAX491E Full-Duplex RS-485 NetworkFigure 25. MAX481E/MAX483E/MAX485E/MAX487E/MAX1487E Typical Half-Duplex RS-485 NetworkM A X 481E /M A X 483E /M A X 485E /M A X 487E –M A X 491E /M A X 1487E±15kV ESD-Protected, Slew-Rate-Limited, Low-Power, RS-485/RS-422 Transceivers 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.16____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600©2003 Maxim Integrated ProductsPrinted USAis a registered trademark of Maxim Integrated Products.Package InformationFor the latest package outline information, go to /packages .Ordering Information (continued)Selector GuideChip InformationTRANSISTOR COUNT: 295。

General DescriptionThe MAX13080E–MAX13089E +5.0V, ±15kV ESD-protect-ed, RS-485/RS-422 transceivers feature one driver and one receiver. These devices include fail-safe circuitry,guaranteeing a logic-high receiver output when receiver inputs are open or shorted. The receiver outputs a logic-high if all transmitters on a terminated bus are disabled (high impedance). The MAX13080E–MAX13089E include a hot-swap capability to eliminate false transitions on the bus during power-up or hot insertion.The MAX13080E/MAX13081E/MAX13082E feature reduced slew-rate drivers that minimize EMI and reduce reflections caused by improperly terminated cables, allowing error-free data transmission up to 250kbps. The MAX13083E/MAX13084E/MAX13085E also feature slew-rate-limited drivers but allow transmit speeds up to 500kbps. The MAX13086E/MAX13087E/MAX13088E driver slew rates are not limited, making transmit speeds up to 16Mbps possible. The MAX13089E slew rate is pin selectable for 250kbps,500kbps, and 16Mbps.The MAX13082E/MAX13085E/MAX13088E are intended for half-duplex communications, and the MAX13080E/MAX13081E/MAX13083E/MAX13084E/MAX13086E/MAX13087E are intended for full-duplex communica-tions. The MAX13089E is selectable for half-duplex or full-duplex operation. It also features independently programmable receiver and transmitter output phase through separate pins.The MAX13080E–MAX13089E transceivers draw 1.2mA of supply current when unloaded or when fully loaded with the drivers disabled. All devices have a 1/8-unit load receiver input impedance, allowing up to 256transceivers on the bus.The MAX13080E/MAX13083E/MAX13086E/MAX13089E are available in 14-pin PDIP and 14-pin SO packages.The MAX13081E/MAX13082E/MAX13084E/MAX13085E/MAX13087E/MAX13088E are available in 8-pin PDIP and 8-pin SO packages. The devices operate over the com-mercial, extended, and automotive temperature ranges.ApplicationsUtility Meters Lighting Systems Industrial Control Telecom Security Systems Instrumentation ProfibusFeatures♦+5.0V Operation♦Extended ESD Protection for RS-485/RS-422 I/O Pins±15kV Human Body Model ♦True Fail-Safe Receiver While Maintaining EIA/TIA-485 Compatibility ♦Hot-Swap Input Structures on DE and RE ♦Enhanced Slew-Rate Limiting Facilitates Error-Free Data Transmission(MAX13080E–MAX13085E/MAX13089E)♦Low-Current Shutdown Mode (Except MAX13081E/MAX13084E/MAX13087E)♦Pin-Selectable Full-/Half-Duplex Operation (MAX13089E)♦Phase Controls to Correct for Twisted-Pair Reversal (MAX13089E)♦Allow Up to 256 Transceivers on the Bus ♦Available in Industry-Standard 8-Pin SO PackageMAX13080E–MAX13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers________________________________________________________________Maxim Integrated Products 1Ordering Information19-3590; Rev 1; 4/05For pricing, delivery, and ordering information,please contact Maxim/Dallas Direct!at 1-888-629-4642, or visit Maxim’s website at .Selector Guide, Pin Configurations, and Typical Operating Circuits appear at end of data sheet.Ordering Information continued at end of data sheet.M A X 13080E –M A X 13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers 2_______________________________________________________________________________________ABSOLUTE MAXIMUM RATINGSDC ELECTRICAL CHARACTERISTICS(V CC = +5.0V ±10%, T A = T MIN to T MAX , unless otherwise noted. Typical values are at V CC = +5.0V and T A = +25°C.) (Note 1)Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.(All Voltages Referenced to GND)Supply Voltage (V CC ).............................................................+6V Control Input Voltage (RE , DE, SLR,H/F , TXP, RXP)......................................................-0.3V to +6V Driver Input Voltage (DI)...........................................-0.3V to +6V Driver Output Voltage (Z, Y, A, B).............................-8V to +13V Receiver Input Voltage (A, B)....................................-8V to +13V Receiver Input VoltageFull Duplex (A, B)..................................................-8V to +13V Receiver Output Voltage (RO)....................-0.3V to (V CC + 0.3V)Driver Output Current.....................................................±250mAContinuous Power Dissipation (T A = +70°C)8-Pin SO (derate 5.88mW/°C above +70°C).................471mW 8-Pin Plastic DIP (derate 9.09mW/°C above +70°C).....727mW 14-Pin SO (derate 8.33mW/°C above +70°C)...............667mW 14-Pin Plastic DIP (derate 10.0mW/°C above +70°C)...800mW Operating Temperature RangesMAX1308_EC_ _.................................................0°C to +75°C MAX1308_EE_ _..............................................-40°C to +85°C MAX1308_EA_ _............................................-40°C to +125°C Junction Temperature......................................................+150°C Storage Temperature Range.............................-65°C to +150°C Lead Temperature (soldering, 10s).................................+300°CMAX13080E–MAX13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers_______________________________________________________________________________________3DC ELECTRICAL CHARACTERISTICS (continued)(V CC = +5.0V ±10%, T A = T MIN to T MAX , unless otherwise noted. Typical values are at V CC = +5.0V and T A = +25°C.) (Note 1)M A X 13080E –M A X 13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers 4_______________________________________________________________________________________DRIVER SWITCHING CHARACTERISTICSMAX13080E/MAX13081E/MAX13082E/MAX13089E WITH SRL = UNCONNECTED (250kbps)(V CC = +5.0V ±10%, T A = T MIN to T MAX , unless otherwise noted. Typical values are at V CC = +5.0V and T A = +25°C.)RECEIVER SWITCHING CHARACTERISTICSMAX13080E/MAX13081E/MAX13082E/MAX13089E WITH SRL = UNCONNECTED (250kbps)(V CC = +5.0V ±10%, T A = T MIN to T MAX , unless otherwise noted. Typical values are at V CC = +5.0V and T A = +25°C.)MAX13080E–MAX13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers_______________________________________________________________________________________5DRIVER SWITCHING CHARACTERISTICSMAX13083E/MAX13084E/MAX13085E/MAX13089E WITH SRL = V CC (500kbps)(V CC = +5.0V ±10%, T A = T MIN to T MAX , unless otherwise noted. Typical values are at V CC = +5.0V and T A = +25°C.)RECEIVER SWITCHING CHARACTERISTICSMAX13083E/MAX13084E/MAX13085E/MAX13089E WITH SRL = V CC (500kbps)(V CC = +5.0V ±10%, T A = T MIN to T MAX , unless otherwise noted. Typical values are at V CC = +5.0V and T A = +25°C.)M A X 13080E –M A X 13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers 6_______________________________________________________________________________________DRIVER SWITCHING CHARACTERISTICSMAX13086E/MAX13087E/MAX13088E/MAX13089E WITH SRL = GND (16Mbps)(V CC = +5.0V ±10%, T A = T MIN to T MAX , unless otherwise noted. Typical values are at V CC = +5.0V and T A = +25°C.)RECEIVER SWITCHING CHARACTERISTICSMAX13086E/MAX13087E/MAX13088E/MAX13089E WITH SRL = GND (16Mbps)(V CC = +5.0V ±10%, T A = T MIN to T MAX , unless otherwise noted. Typical values are at V CC = +5.0V and T A = +25°C.)Note 2:∆V OD and ∆V OC are the changes in V OD and V OC , respectively, when the DI input changes state.Note 3:The short-circuit output current applies to peak current just prior to foldback current limiting. The short-circuit foldback outputcurrent applies during current limiting to allow a recovery from bus contention.MAX13080E–MAX13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers_______________________________________________________________________________________70.800.901.501.101.001.201.301.401.60-40-10520-253550958011065125SUPPLY CURRENT vs. TEMPERATURETEMPERATURE (°C)S U P P L Y C U R R E N T (m A )0201040305060021345OUTPUT CURRENTvs. RECEIVER OUTPUT-HIGH VOLTAGEM A X 13080E -89E t o c 02OUTPUT HIGH VOLTAGE (V)O U T P U T C U R R E N T (m A )20104030605070021345OUTPUT CURRENTvs. RECEIVER OUTPUT-LOW VOLTAGEM A X 13080E -89E t o c 03OUTPUT LOW VOLTAGE (V)O U T P U T C U R R E N T (m A )4.04.44.24.84.65.25.05.4RECEIVER OUTPUT-HIGH VOLTAGEvs. TEMPERATURETEMPERATURE (°C)O U T P U T H I G H V O L T A G E (V )-40-10520-2535509580110651250.10.70.30.20.40.50.60.8RECEIVER OUTPUT-LOW VOLTAGEvs. TEMPERATURETEMPERATURE (°C)O U T P U T L O W V O L T A G E (V )-40-10520-25355095801106512502040608010012014016012345DRIVER DIFFERENTIAL OUTPUT CURRENT vs. DIFFERENTIAL OUTPUT VOLTAGEDIFFERENTIAL OUTPUT VOLTAGE (V)D I F FE R E N T I A L O U T P U T C U R R E N T (m A )2.02.82.43.63.24.44.04.8DRIVER DIFFERENTIAL OUTPUT VOLTAGE vs. TEMPERATURED I F FE R E N T I A L O U T P U T V O L T A G E (V )-40-10520-253550958011065125TEMPERATURE (°C)40201008060120140180160200-7-5-4-6-3-2-1012354OUTPUT CURRENT vs. TRANSMITTEROUTPUT-HIGH VOLTAGEOUTPUT HIGH VOLTAGE (V)O U T P U T C U R R E N T (m A )60402080100120140160180200042681012OUTPUT CURRENT vs. TRANSMITTEROUTPUT-LOW VOLTAGEOUTPUT-LOW VOLTAGE (V)O U T P U T C U R R E N T (m A )Typical Operating Characteristics(V CC = +5.0V, T A = +25°C, unless otherwise noted.)M A X 13080E –M A X 13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers 8_______________________________________________________________________________________21543679810SHUTDOWN CURRENT vs. TEMPERATUREM A X 13080E -89E t o c 10S H U T D O W N C U R R E N T (µA )-40-10520-253550958011065125TEMPERATURE (°C)600800700100090011001200DRIVER PROPAGATION DELAY vs. TEMPERATURE (250kbps)D R I VE R P R O P A G A T I O N D E L A Y (n s )-40-10520-253550958011065125TEMPERATURE (°C)300400350500450550600DRIVER PROPAGATION DELAY vs. TEMPERATURE (500kbps)D R I VE R P R O P A G A T I O N D E L A Y (n s )-40-10520-253550958011065125TEMPERATURE (°C)1070302040506080DRIVER PROPAGATION DELAY vs. TEMPERATURE (16Mbps)D R I VE R P R O P A G A T I O N D E L A Y (n s )-40-10520-253550958011065125TEMPERATURE (°C)40201008060120140160180RECEIVER PROPAGATION DELAYvs. TEMPERATURE (250kpbs AND 500kbps)R E C E I V E R P R O P A G A T I O N D E L A Y (n s )-40-10520-253550958011065125TEMPERATURE (°C)40201008060120140160180RECEIVER PROPAGATION DELAYvs. TEMPERATURE (16Mbps)R EC E I V E R P R O P A G AT I O N D E L A Y (n s )-40-10520-253550958011065125TEMPERATURE (°C)2µs/div DRIVER PROPAGATION DELAY (250kbps)DI 2V/divV Y - V Z 5V/divR L = 100Ω200ns/divRECEIVER PROPAGATION DELAY(250kbps AND 500kbps)V A - V B 5V/divRO 2V/divTypical Operating Characteristics (continued)(V CC = +5.0V, T A = +25°C, unless otherwise noted.)MAX13080E–MAX13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers_______________________________________________________________________________________9Test Circuits and Waveforms400ns/divDRIVER PROPAGATION DELAY (500kbps)DI 2V/divR L = 100ΩV Y - V Z 5V/div10ns/div DRIVER PROPAGATION DELAY (16Mbps)DI 2V/divR L = 100ΩV Y 2V/divV Z 2V/div40ns/divRECEIVER PROPAGATION DELAY (16Mbps)V B 2V/divR L = 100ΩRO 2V/divV A 2V/divTypical Operating Characteristics (continued)(V CC = +5.0V, T A = +25°C, unless otherwise noted.)Figure 2. Driver Timing Test CircuitM A X 13080E –M A X 13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers 10______________________________________________________________________________________Test Circuits and Waveforms (continued)Figure 4. Driver Enable and Disable Times (t DHZ , t DZH , t DZH(SHDN))DZL DLZ DLZ(SHDN)MAX13080E–MAX13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 TransceiversTest Circuits and Waveforms (continued)Figure 6. Receiver Propagation Delay Test CircuitM A X 13080E –M A X 13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 TransceiversMAX13080E–MAX13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 TransceiversMAX13080E/MAX13083E/MAX13086EMAX13081E/MAX13084E/MAX13086E/MAX13087EFunction TablesM A X 13080E –M A X 13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers MAX13082E/MAX13085E/MAX13088EFunction Tables (continued)MAX13089EDetailed Description The MAX13080E–MAX13089E high-speed transceivers for RS-485/RS-422 communication contain one driver and one receiver. These devices feature fail-safe circuit-ry, which guarantees a logic-high receiver output when the receiver inputs are open or shorted, or when they are connected to a terminated transmission line with all dri-vers disabled (see the Fail-Safe section). The MAX13080E/MAX13082E/MAX13083E/MAX13085E/ MAX13086E/MAX13088E/MAX13089E also feature a hot-swap capability allowing line insertion without erroneous data transfer (see the Hot Swap Capability section). The MAX13080E/MAX13081E/MAX13082E feature reduced slew-rate drivers that minimize EMI and reduce reflec-tions caused by improperly terminated cables, allowing error-free data transmission up to 250kbps. The MAX13083E/MAX13084E/MAX13085E also offer slew-rate limits allowing transmit speeds up to 500kbps. The MAX13086E/MAX13087E/MAX13088Es’ driver slew rates are not limited, making transmit speeds up to 16Mbps possible. The MAX13089E’s slew rate is selectable between 250kbps, 500kbps, and 16Mbps by driving a selector pin with a three-state driver.The MAX13082E/MAX13085E/MAX13088E are half-duplex transceivers, while the MAX13080E/MAX13081E/ MAX13083E/MAX13084E/MAX13086E/MAX13087E are full-duplex transceivers. The MAX13089E is selectable between half- and full-duplex communication by driving a selector pin (H/F) high or low, respectively.All devices operate from a single +5.0V supply. Drivers are output short-circuit current limited. Thermal-shutdown circuitry protects drivers against excessive power dissi-pation. When activated, the thermal-shutdown circuitry places the driver outputs into a high-impedance state.Receiver Input Filtering The receivers of the MAX13080E–MAX13085E, and the MAX13089E when operating in 250kbps or 500kbps mode, incorporate input filtering in addition to input hysteresis. This filtering enhances noise immunity with differential signals that have very slow rise and fall times. Receiver propagation delay increases by 25% due to this filtering.Fail-Safe The MAX13080E family guarantees a logic-high receiver output when the receiver inputs are shorted or open, or when they are connected to a terminated transmission line with all drivers disabled. This is done by setting the receiver input threshold between -50mV and -200mV. If the differential receiver input voltage (A - B) is greater than or equal to -50mV, RO is logic-high. If (A - B) is less than or equal to -200mV, RO is logic-low. In the case of a terminated bus with all transmitters disabled, the receiv-er’s differential input voltage is pulled to 0V by the termi-nation. With the receiver thresholds of the MAX13080E family, this results in a logic-high with a 50mV minimumnoise margin. Unlike previous fail-safe devices, the-50mV to -200mV threshold complies with the ±200mVEIA/TIA-485 standard.Hot-Swap Capability (Except MAX13081E/MAX13084E/MAX13087E)Hot-Swap InputsWhen circuit boards are inserted into a hot or powered backplane, differential disturbances to the data buscan lead to data errors. Upon initial circuit board inser-tion, the data communication processor undergoes itsown power-up sequence. During this period, the processor’s logic-output drivers are high impedanceand are unable to drive the DE and RE inputs of these devices to a defined logic level. Leakage currents up to±10µA from the high-impedance state of the proces-sor’s logic drivers could cause standard CMOS enableinputs of a transceiver to drift to an incorrect logic level. Additionally, parasitic circuit board capacitance couldcause coupling of V CC or GND to the enable inputs. Without the hot-swap capability, these factors could improperly enable the transceiver’s driver or receiver.When V CC rises, an internal pulldown circuit holds DElow and RE high. After the initial power-up sequence,the pulldown circuit becomes transparent, resetting thehot-swap tolerable input.Hot-Swap Input CircuitryThe enable inputs feature hot-swap capability. At theinput there are two NMOS devices, M1 and M2 (Figure 9). When V CC ramps from zero, an internal 7µstimer turns on M2 and sets the SR latch, which alsoturns on M1. Transistors M2, a 1.5mA current sink, andM1, a 500µA current sink, pull DE to GND through a5kΩresistor. M2 is designed to pull DE to the disabledstate against an external parasitic capacitance up to100pF that can drive DE high. After 7µs, the timer deactivates M2 while M1 remains on, holding DE low against three-state leakages that can drive DE high. M1 remains on until an external source overcomes the required input current. At this time, the SR latch resetsand M1 turns off. When M1 turns off, DE reverts to a standard, high-impedance CMOS input. Whenever V CCdrops below 1V, the hot-swap input is reset.For RE there is a complementary circuit employing two PMOS devices pulling RE to V CC. MAX13080E–MAX13089E+5.0V, ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 TransceiversM A X 13080E –M A X 13089EMAX13089E ProgrammingThe MAX13089E has several programmable operating modes. Transmitter rise and fall times are programma-ble, resulting in maximum data rates of 250kbps,500kbps, and 16Mbps. To select the desired data rate,drive SRL to one of three possible states by using a three-state driver: V CC , GND, or unconnected. F or 250kbps operation, set the three-state device in high-impedance mode or leave SRL unconnected. F or 500kbps operation, drive SRL high or connect it to V CC .F or 16Mbps operation, drive SRL low or connect it to GND. SRL can be changed during operation without interrupting data communications.Occasionally, twisted-pair lines are connected backward from normal orientation. The MAX13089E has two pins that invert the phase of the driver and the receiver to cor-rect this problem. F or normal operation, drive TXP and RXP low, connect them to ground, or leave them uncon-nected (internal pulldown). To invert the driver phase,drive TXP high or connect it to V CC . To invert the receiver phase, drive RXP high or connect it to V CC . Note that the receiver threshold is positive when RXP is high.The MAX13089E can operate in full- or half-duplex mode. Drive H/F low, leave it unconnected (internal pulldown), or connect it to GND for full-duplex opera-tion. Drive H/F high for half-duplex operation. In full-duplex mode, the pin configuration of the driver and receiver is the same as that of a MAX13080E. In half-duplex mode, the receiver inputs are internally connect-ed to the driver outputs through a resistor-divider. This effectively changes the function of the device’s outputs.Y becomes the noninverting driver output and receiver input, Z becomes the inverting driver output and receiver input. In half-duplex mode, A and B are still connected to ground through an internal resistor-divider but they are not internally connected to the receiver.±15kV ESD ProtectionAs with all Maxim devices, ESD-protection structures are incorporated on all pins to protect against electro-static discharges encountered during handling and assembly. The driver outputs and receiver inputs of the MAX13080E family of devices have extra protection against static electricity. Maxim’s engineers have devel-oped state-of-the-art structures to protect these pins against ESD of ±15kV without damage. The ESD struc-tures withstand high ESD in all states: normal operation,shutdown, and powered down. After an ESD event, the MAX13080E–MAX13089E keep working without latchup or damage.ESD protection can be tested in various ways. The transmitter outputs and receiver inputs of the MAX13080E–MAX13089E are characterized for protec-tion to the following limits:•±15kV using the Human Body Model•±6kV using the Contact Discharge method specified in IEC 61000-4-2ESD Test ConditionsESD performance depends on a variety of conditions.Contact Maxim for a reliability report that documents test setup, test methodology, and test results.Human Body ModelFigure 10a shows the Human Body Model, and Figure 10b shows the current waveform it generates when dis-charged into a low impedance. This model consists of a 100pF capacitor charged to the ESD voltage of interest,which is then discharged into the test device through a 1.5k Ωresistor.IEC 61000-4-2The IEC 61000-4-2 standard covers ESD testing and performance of finished equipment. However, it does not specifically refer to integrated circuits. The MAX13080E family of devices helps you design equip-ment to meet IEC 61000-4-2, without the need for addi-tional ESD-protection components.+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 TransceiversThe major difference between tests done using the Human Body Model and IEC 61000-4-2 is higher peak current in IEC 61000-4-2 because series resistance is lower in the IEC 61000-4-2 model. Hence, the ESD with-stand voltage measured to IEC 61000-4-2 is generally lower than that measured using the Human Body Model. Figure 10c shows the IEC 61000-4-2 model, and Figure 10d shows the current waveform for IEC 61000-4-2 ESD Contact Discharge test.Machine Model The machine model for ESD tests all pins using a 200pF storage capacitor and zero discharge resis-tance. The objective is to emulate the stress caused when I/O pins are contacted by handling equipment during test and assembly. Of course, all pins require this protection, not just RS-485 inputs and outputs.Applications Information256 Transceivers on the BusThe standard RS-485 receiver input impedance is 12kΩ(1-unit load), and the standard driver can drive up to 32-unit loads. The MAX13080E family of transceivers has a1/8-unit load receiver input impedance (96kΩ), allowingup to 256 transceivers to be connected in parallel on one communication line. Any combination of these devices,as well as other RS-485 transceivers with a total of 32-unit loads or fewer, can be connected to the line.Reduced EMI and ReflectionsThe MAX13080E/MAX13081E/MAX13082E feature reduced slew-rate drivers that minimize EMI and reduce reflections caused by improperly terminated cables, allowing error-free data transmission up to250kbps. The MAX13083E/MAX13084E/MAX13085Eoffer higher driver output slew-rate limits, allowing transmit speeds up to 500kbps. The MAX13089E withSRL = V CC or unconnected are slew-rate limited. WithSRL unconnected, the MAX13089E error-free data transmission is up to 250kbps. With SRL connected toV CC,the data transmit speeds up to 500kbps. MAX13080E–MAX13089E+5.0V, ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 TransceiversM A X 13080E –M A X 13089ELow-Power Shutdown Mode (Except MAX13081E/MAX13084E/MAX13087E)Low-power shutdown mode is initiated by bringing both RE high and DE low. In shutdown, the devices typically draw only 2.8µA of supply current.RE and DE can be driven simultaneously; the devices are guaranteed not to enter shutdown if RE is high and DE is low for less than 50ns. If the inputs are in this state for at least 700ns, the devices are guaranteed to enter shutdown.Enable times t ZH and t ZL (see the Switching Characteristics section) assume the devices were not in a low-power shutdown state. Enable times t ZH(SHDN)and t ZL(SHDN)assume the devices were in shutdown state. It takes drivers and receivers longer to become enabled from low-power shutdown mode (t ZH(SHDN), t ZL(SHDN))than from driver/receiver-disable mode (t ZH , t ZL ).Driver Output ProtectionTwo mechanisms prevent excessive output current and power dissipation caused by faults or by bus contention.The first, a foldback current limit on the output stage,provides immediate protection against short circuits over the whole common-mode voltage range (see the Typical Operating Characteristics ). The second, a thermal-shut-down circuit, forces the driver outputs into a high-imped-ance state if the die temperature exceeds +175°C (typ).Line LengthThe RS-485/RS-422 standard covers line lengths up to 4000ft. F or line lengths greater than 4000ft, use the repeater application shown in Figure 11.Typical ApplicationsThe MAX13082E/MAX13085E/MAX13088E/MAX13089E transceivers are designed for bidirectional data commu-nications on multipoint bus transmission lines. F igures 12 and 13 show typical network applications circuits. To minimize reflections, terminate the line at both ends in its characteristic impedance, and keep stub lengths off the main line as short as possible. The slew-rate-lim-ited MAX13082E/MAX13085E and the two modes of the MAX13089E are more tolerant of imperfect termination.Chip InformationTRANSISTOR COUNT: 1228PROCESS: BiCMOS+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 TransceiversFigure 11. Line Repeater for MAX13080E/MAX13081E/MAX13083E/MAX13084E/MAX13086E/MAX13087E/MAX13089E in Full-Duplex Mode+5.0V, ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 TransceiversMAX13080E–MAX13089EM A X 13080E –M A X 13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 TransceiversPin Configurations and Typical Operating CircuitsMAX13080E–MAX13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers______________________________________________________________________________________21Pin Configurations and Typical Operating Circuits (continued)M A X 13080E –M A X 13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers 22______________________________________________________________________________________Ordering Information (continued)MAX13080E–MAX13089E+5.0V , ±15kV ESD-Protected, Fail-Safe, Hot-Swap, RS-485/RS-422 Transceivers______________________________________________________________________________________23Package Information (continued)(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,go to /packages .)。

o True Fail-Safe Receiver While Maintaining EIA/TIA-485 Compatibility
o Hot-Swap Input Structures on DE and RE
o Enhanced Slew-Rate Limiting Facilitates ErrorFree Data Transmission (MAX13080E–MAX13084E/MAX13089E)
UCSP is Taetrleadceommark of Maxim Integrated Products, Inc.
Security Systems
Instrumentation
Profibus
Features
o +5.0V Operation
o Extended ESD Protection for RS-485/RS-422 I/O Pins ±15kV Human Body Model
o Low-Current Shutdown Mode (Except MAX13081E/MAX13084E/MAX13087E)
o Pin-Selectable Full-/Half-Duplex Operation (MAX13089E)
o Phase Controls to Correct for Twisted-Pair Reversal (MAX13089E)
MAX13080ECPD+
0°C to +70°C 14 PDIP
MAX13080ECSD+
0°C to +70°C 14 SO
MAX13080EEPD+ -40°C to +85°C 14 PDIP

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。