Low-Power, Slew-Rate-Limited RS-485/RS-422 …

1 For free samples & the latest literature: , or phone 1-800-998-8800_____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 EMI andreduce reflections caused by improperly terminated cables,thus allowing error-free data transmission up to driver slew rates of the MAX481, MAX485, MAX490,MAX491, and MAX1487 are not limited , allowing them totransmit up to transceivers draw between 120 A and 500 A ofsupply current when unloaded or fully loaded with disableddrivers.

2 Additionally, the MAX481, MAX483, and MAX487have a low-current shutdown mode in which they consumeonly A. All parts operate from a single 5V 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 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 RS-485 TransceiversLow- power RS-422 TransceiversLevel TranslatorsTransceivers for EMI-Sensitive ApplicationsIndustrial-Control Local Area Networks_____Features In MAX Package: Smallest 8-Pin SO slew -Rate limited for Error-Free DataTransmission (MAX483/487/488/489) A Low-Current Shutdown Mode(MAX481/483/487) Low Quiescent Current.

3 120 A (MAX483/487/488/489)230 A (MAX1487)300 A (MAX481/485/490/491) -7V to +12V Common-Mode Input Voltage Range Three-State Outputs 30ns Propagation Delays, 5ns Skew (MAX481/485/490/491/1487) Full-Duplex and Half-Duplex Versions Available Operate from a Single 5V Supply Allows up to 128 Transceivers on the Bus(MAX487/MAX1487) Current-Limiting and Thermal Shutdown forDriver Overload Protection_____Ordering InformationOrdering Information continued at end of data sheet.* Contact factory for dice MAX491/MAX1487 Low- power , slew -Rate-LimitedRS-485/RS-422 Transceivers_____Maxim Integrated Products1 MAX481 MAX483 MAX485 MAX487 MAX488 MAX489 MAX490 MAX491 MAX1487 PART NUMBERHALF/FULL DUPLEXDATA RATE (Mbps) slew -RATE LIMITEDLOW- power SHUTDOWNRECEIVER/ DRIVER ENABLEQUIESCENT CURRENT ( A)NUMBER OF TRANSMITTERS ON BUSPIN COUNTHalf Half Half Half Full Full Full Full Yes No Yes Yes Yes No No NoYes Yes No Yes No No No No NoYes Yes Yes Yes No Yes No Yes Yes300 120 300 120 120 120 300 300 23032 32 32 128 32 32 32 32 1288 8 8 8 8 14 8 14 8_____Selection Table19-0122; Rev 5; 2/96 PARTTEMP.

4 RANGEPIN-PACKAGEMAX481 CPA0 C to +70 C8 Plastic DIPMAX481 CSA0 C to +70 C8 SOMAX481 CUA0 C to +70 C8 MAXMAX481C/D0 C to +70 CDice*MAX481/MAX483/MAX485/MAX487 MAX491/MAX1487 Low- power , slew -Rate-LimitedRS-485/RS-422 Transceivers2_____ABSOLUTE MAXIMUM RATINGSS upply Voltage (VCC) ..12 VControl Input Voltage ( R E , DE).. to (VCC+ )Driver Input Voltage (DI).. to (VCC+ )Driver Output Voltage (A, B)..-8V to + Input Voltage (A, B)..-8V to + Output Voltage (RO).. to (VCC+ )Continuous power Dissipation (TA= +70 C)8-Pin Plastic DIP (derate C above +70 C) ..727mW14-Pin Plastic DIP (derate C above +70 C)..800mW8-Pin SO (derate C above +70 C)..471mW14-Pin SO (derate C above +70 C).

5 667mW8-Pin MAX (derate C above +70 C) ..830mW8-Pin CERDIP (derate C above +70 C)..640mW14-Pin CERDIP (derate C above +70 C)..727mWOperating Temperature RangesMAX4_ _C_ _/MAX1487C_ A ..0 C to +70 CMAX4_ _E_ _/MAX1487E_ A ..-40 C to +85 CMAX4_ _MJ_/MAX1487 MJA ..-55 C to +125 CStorage Temperature Range ..-65 C to +160 CLead Temperature (soldering, 10sec) ..+300 CDC ELECTRICAL CHARACTERISTICS(VCC= 5V 5%, TA= TMINto TMAX, 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 functionaloperation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied.

6 Exposure toabsolute maximum rating conditions for extended periods may affect device -7 VVIN= 12 VVIN= -7 VVIN= 12 VInput Current(A, B)IIN2 VTHk 48-7V VCM 12V, MAX487/MAX1487 RINR eceiver Input Resistance-7V VCM 12V, all devices exceptMAX487/MAX1487R = 27 (RS-485), Figure VO = 50 (RS-422)IO = 4mA, VID= -200mVIO= -4mA, VID= 200mVVCM= 0V-7V VCM 12 VDE, DI, R E DE, DI, R E MAX487/MAX1487, DE = 0V, VCC= 0V or , DI, R E R = 27 or 50 , Figure 4R = 27 or 50 , Figure 4R = 27 or 50 , Figure 4DE = 0V;VCC= 0V or ,all devices exceptMAX487/MAX1487 CONDITIONSk 12 A 1 IOZRT hree-State (high impedance)Output Current at Output Low Output High VoltagemV70 VTHR eceiver Input Differential Driver Output(with load)V2V5 VOD1 Differential Driver Output (no load)

7 A 2 IIN1 Input Low High VODC hange in Magnitude of DriverCommon-Mode Output Voltagefor Complementary Output VODC hange in Magnitude of DriverDifferential Output Voltage forComplementary Output StatesV3 VOCD river Common-Mode OutputVoltageUNITSMINTYPMAXSYMBOLPARAMET ERMAX481/MAX483/MAX485/MAX487 MAX491/MAX1487 Low- power , slew -Rate-LimitedRS-485/RS-422 Transceivers_____ 3 SWITCHING CHARACTERISTICS MAX481/MAX485, MAX490/MAX491, MAX1487(VCC= 5V 5%, TA= TMINto TMAX, unless otherwise noted.) (Notes 1, 2)DC ELECTRICAL CHARACTERISTICS (continued)(VCC= 5V 5%, TA= TMINto TMAX, unless otherwise noted.) (Notes 1, 2)mA7950V VO VCCIOSRR eceiver Short-Circuit CurrentmA35250-7V VO 12V (Note 4)IOSD2 Driver Short-Circuit Current,VO= LowmA35250-7V VO 12V (Note 4)IOSD1 Driver Short-Circuit Current,VO= HighMAX1487, R E = 0V or VCC250400350650ns103060tPHLD river Rise or Fall TimeFigures 6 and 8, RDIFF= 54 , CL1= CL2= 100pFnsMAX490M, MAX491 MMAX490C/E, MAX491C/E2090150 MAX481, MAX485, MAX1487 MAX490M, MAX491 MMAX490C/E, MAX491C/EMAX481, MAX485, MAX1487 Figures 6 and 8, RDIFF= 54 ,CL1= CL2= 100pFMAX481 (Note 5)

8 Figures 5 and 11, CRL= 15pF, S2 closedFigures 5 and 11, CRL= 15pF, S1 closedFigures 5 and 11, CRL= 15pF, S2 closedFigures 5 and 11, CRL= 15pF, S1 closedFigures 6 and 10, RDIFF= 54 ,CL1= CL2= 100pFFigures 6 and 8,RDIFF= 54 ,CL1= CL2= 100pFFigures 6 and 10,RDIFF= 54 ,CL1= CL2= 100pFCONDITIONSns510tSKEWns50200600tSHDN Time to Data Ratens2050tHZReceiver Disable Time from Highns103060tPLH2050tLZReceiver Disable Time from Lowns2050tZHDriver Input to OutputReceiver Enable to Output Highns2050tZLReceiver Enable to Output Low2090200nsns134070tHZtSKDD river Disable Time from High|tPLH- tPHL|DifferentialReceiver Skewns4070tLZDriver Disable Time from Lowns4070tZLDriver Enable to Output Low31540ns51525ns31540tR, tF2090200 Driver Output Skew to OutputtPLH, tPHLR eceiver Input to Output4070tZHDriver Enable to Output HighUNITSMINTYPMAXSYMBOLPARAMETERCONDITI ONSUNITSMINTYPMAXSYMBOLPARAMETER23040030 0500 MAX481/MAX485.

9 R E = 0V or VCC500900 MAX490/MAX491,DE, DI, R E = 0V or VCC300500 MAX488/MAX489,DE, DI, R E = 0V or VCC120250DE = VCC300500DE = 0 VDE = VCCDE = 0V AMAX481/483/487, DE = 0V, R E = Current in Shutdown 120250 ICCNo-Load Supply Current(Note 3)DE = 5 VDE = 0 VMAX483 MAX487 MAX483/MAX487, R E = 0V or VCCF igures 7 and 9, CL= 100pF, S2 closedFigures 7 and 9, CL= 100pF, S1 closedFigures 7 and 9, CL= 15pF, S1 closedFigures 7 and 9, CL= 15pF, S2 closed AMAX481/MAX483/MAX485/MAX487 MAX491/MAX1487 Low- power , slew -Rate-LimitedRS-485/RS-422 Transceivers4_____SWITCHING CHARACTERISTICS MAX483, MAX487/MAX488/MAX489(VCC= 5V 5%, TA= TMINto TMAX, unless otherwise noted.) (Notes 1, 2)SWITCHING CHARACTERISTICS MAX481/MAX485, MAX490/MAX491, MAX1487 (continued)(VCC= 5V 5%, TA= TMINto TMAX, unless otherwise noted.)

10 (Notes 1, 2)3001000 Figures 7 and 9, CL= 100pF, S2 closedFigures 7 and 9, CL= 100pF, S1 closedFigures 5 and 11, CL= 15pF, S2 closed,A - B = 2 VCONDITIONSns40100tZH(SHDN)Driver Enable from Shutdown toOutput High (MAX481)nsFigures 5 and 11, CL= 15pF, S1 closed,B - A = 2 VtZL(SHDN)Receiver Enable from Shutdownto Output Low (MAX481)ns40100tZL(SHDN)Driver Enable from Shutdown toOutput Low (MAX481)ns3001000tZH(SHDN)Receiver Enable from Shutdownto Output High (MAX481)UNITSMINTYPMAXSYMBOLPARAMETERtPL HtSKEWF igures 6 and 8, RDIFF= 54 ,CL1= CL2= 100pFtPHLF igures 6 and 8, RDIFF= 54 ,CL1= CL2= 100pFDriver Input to OutputDriver Output Skew to Outputns100800nsns2000 MAX483/MAX487, Figures 7 and 9,CL= 100pF, S2 closedtZH(SHDN)Driver Enable from Shutdown toOutput High 2502000ns2500 MAX483/MAX487, Figures 5 and 11,CL= 15pF, S1 closedtZL(SHDN)Receiver Enable from Shutdownto Output Low ns2500 MAX483/MAX487, Figures 5 and 11,CL= 15pF, S2 closedtZH(SHDN)Receiver Enable from Shutdownto Output High ns2000 MAX483/MAX487, Figures 7 and 9,CL= 100pF, S1 closedtZL(SHDN)Driver Enable from Shutdown toOutput Low ns50200600 MAX483/MAX487 (Note 5)