MAX481/MAX483/MAX485/MAX487–MAX491/MAX1487Low-Power, Slew-Rate-LimitedRS-485/RS-422 TransceiversGeneral 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 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.
__Next Generation Device FeaturesoFor 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
oFor 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 TransmittersoFor Multiple Transceiver Applications
MAX3030E–MAX3033E: ±15kV ESD-Protected,+3.3V, Quad RS-422 TransmittersoFor Fail-Safe Applications
MAX3080–MAX3089: Fail-Safe, High-Speed(10Mbps), Slew-Rate-Limited RS-485/RS-422Transceivers
oFor Low-Voltage Applications
MAX3483E/MAX3485E/MAX3486E/MAX3488E/MAX3490E/MAX3491E: +3.3V Powered, ±15kVESD-Protected, 12Mbps, Slew-Rate-Limited,True RS-485/RS-422 Transceivers
Ordering Information appears at end of data sheet.________________________ApplicationsLow-Power RS-485 TransceiversLow-Power RS-422 TransceiversLevel Translators
Transceivers for EMI-Sensitive ApplicationsIndustrial-Control Local Area Networks
______________________________________________________________Selection TablePART NUMBER MAX481 MAX483 MAX485 MAX487 MAX488 MAX489 MAX490 MAX491 MAX1487
HALF/FULL DUPLEX
HalfHalfHalfHalfFullFullFullFullHalf
DATA RATE (Mbps) 2.50.252.50.250.250.252.52.52.5
SLEW-RATE LIMITED
NoYesNoYesYesYesNoNoNo
LOW-RECEIVER/QUIESCENT NUMBER OF
POWER DRIVER CURRENT RECEIVERS ON SHUTDOWN ENABLE (μA) BUS
YesYesNoYesNoNoNoNoNo
YesYesYesYesNoYesNoYesYes
300120300120120120300300230
32323212832323232128
PIN
COUNT 88888148148
19-0122; Rev 10; 9/14MAX481/MAX483/MAX485/MAX487–MAX491/MAX1487Low-Power, Slew-Rate-LimitedRS-485/RS-422 TransceiversDC ELECTRICAL CHARACTERISTICS (continued)
(VCC= 5V ±5%, TA= TMINto TMAX, unless otherwise noted.) (Notes 1, 2)
PARAMETERSYMBOLCONDITIONSMAX488/MAX489,DE, DI, RE= 0V or VCCMAX490/MAX491,DE, DI, RE= 0V or VCCNo-Load Supply Current(Note 3)ICCMAX481/MAX485,RE= 0V or VCCMAX1487,RE= 0V or VCCMAX483/MAX487,RE= 0V or VCCSupply Current in Shutdown Driver Short-Circuit Current,VO= HighDriver Short-Circuit Current,VO= LowReceiver Short-Circuit CurrentISHDNIOSD1IOSD2IOSRDE = VCCDE = 0VDE = VCCDE = 0VDE = 5VMAX483MAX487MINTYP1203005003003002303502501200.135357MAX2505009005005004006504002501025025095μAUNITSDE = 0VMAX481/483/487, DE = 0V, RE= VCC-7V ≤VO≤12V (Note 4)-7V ≤VO≤12V (Note 4)0V ≤VO≤VCCμAmAmAmASWITCHING CHARACTERISTICS—MAX481/MAX485, MAX490/MAX491, MAX1487
(VCC= 5V ±5%, TA= TMINto TMAX, unless otherwise noted.) (Notes 1, 2)
PARAMETER
Driver Input to OutputDriver Output Skew to OutputDriver Rise or Fall TimeDriver Enable to Output HighDriver Enable to Output LowDriver Disable Time from LowDriver Disable Time from HighReceiver Input to Output
SYMBOLCONDITIONStPLHFigures 6 and 8, RDIFF= 54Ω,
CL1= CL2= 100pFtPHL
tSKEWFigures 6 and 8, RDIFF= 54Ω, CL1= CL2= 100pFMAX481, MAX485, MAX1487Figures 6 and 8,tR, tFRDIFF= 54Ω,MAX490C/E, MAX491C/E
CL1= CL2= 100pFMAX490M, MAX491M
tZHFigures 7 and 9, CL= 100pF, S2 closedtZLFigures 7 and 9, CL= 100pF, S1 closedtLZFigures 7 and 9, CL= 15pF, S1 closedtHZFigures 7 and 9, CL= 15pF, S2 closed
Figures 6 and 10,MAX481, MAX485, MAX1487
MAX490C/E, MAX491C/EtPLH, tPHLRDIFF= 54Ω,
CL1= CL2= 100pFMAX490M, MAX491MtSKDtZLtZHtLZtHZfMAXtSHDN
MAX481 (Note 5)
Figures 6 and 10, RDIFF= 54Ω,CL1= CL2= 100pF
Figures 5 and 11, CRL= 15pF, S1 closedFigures 5 and 11, CRL= 15pF, S2 closedFigures 5 and 11, CRL= 15pF, S1 closedFigures 5 and 11, CRL= 15pF, S2 closed
2.550MIN1010353
TYP30305151515404040409090901320202020200
50505050600MAX60601040254070707070200150200
UNITSnsnsnsnsnsnsnsns
202020
|tPLH- tPHL|Differential
Receiver Skew
Receiver Enable to Output LowReceiver Enable to Output HighReceiver Disable Time from LowReceiver Disable Time from HighMaximum Data RateTime to Shutdown
nsnsnsnsnsMbpsns
3
MEMORY存储芯片MAX487ECPA中文规格书 - 图文
