MAX481:Low-Power, Slew-Rate-Limited RS-485/RS-422 Transceivers

The 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 MAX489 feature 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 MAX487 have 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-impedance 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 communications are obtained using the MAX488–MAX491, while the MAX481, MAX483, MAX485, MAX487, and MAX1487 are designed for half-duplex applications.

Key Features
  • For Fault-Tolerant Applications
    • MAX3430: ±80V Fault-Protected, Fail-Safe, 1/4 Unit Load, +3.3V, RS-485 Transceiver
    • MAX3440E–MAX3444E: ±15kV ESD-Protected, ±60V Fault-Protected, 10Mbps, Fail-Safe, RS-485/J1708 Transceivers
  • For Space-Constrained Applications
    • MAX3460–MAX3464: +5V, Fail-Safe, 20Mbps, PROFIBUS RS-485/RS-422 Transceivers
    • MAX3362: +3.3V, High-Speed, RS-485/RS-422 Transceiver 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
  • For Multiple Transceiver Applications
    • MAX3030E–MAX3033E: ±15kV ESD-Protected, +3.3V, Quad RS-422 Transmitters
  • For Fail-Safe Applications
    • MAX3080–MAX3089: Fail-Safe, High-Speed (10Mbps), Slew-Rate-Limited RS-485/RS-422 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 Transceivers
MAX1487, MAX481, MAX483, MAX485, MAX487, MAX488, MAX489, MAX490, MAX491: Pin Configuration and Typical Operating Circuit
MAX1487, MAX481, MAX483, MAX485, MAX487, MAX488, MAX489, MAX490, MAX491: Pin Configuration and Typical Operating Circuit
Applications/Uses
  • Industrial-Control Local Area Networks
  • Level Translators
  • Low-Power RS-422 Transceivers
  • Low-Power RS-485 Transceivers
  • Transceivers for EMI-Sensitive Applications
DataSheet
titleDownload file
MAX1487-MAX491 Data SheetMAX1487-MAX491.pdf
Parametrics
Part NumberTx/RxDuplexVSUPPLY
(V)
ICC
(mA)
Data Rate
(kbps)
Tx ENRx ENICC (Shutdn.)
(µA)
Rx/Tx on BusRx Failsafe w/ InputsSlew Rate LimitingOper. Temp.
(°C)
Package/PinsBudgetary
Price
typmintypSee Notes
MAX14871Tx + 1RxHalf50.32500YesYes-128OpenNo-55 to +125
-40 to +85
0 to +70
µMAX/8
PDIP(N)/8
SOIC(N)/8
$1.54 @1k
MAX481Half0.52500YesYes0.132µMAX/8
CDIP(N)/8
PDIP(N)/8
SOIC(N)/8
MAX483Half0.35250YesYes0.132µMAX/8
CDIP(N)/8
PDIP(N)/8
SOIC(N)/8
MAX485Half0.52500YesYes-32µMAX/8
CDIP(N)/8
PDIP(N)/8
SOIC(N)/8
MAX487Half0.25250YesYes0.1128µMAX/8
CDIP(N)/8
PDIP(N)/8
SOIC(N)/8
MAX488Full0.12250NoNo-32µMAX/8
CDIP(N)/8
PDIP(N)/8
SOIC(N)/8
MAX489Full0.12250YesYes-32CDIP(N)/14
PDIP(N)/14
SOIC(N)/14
MAX490Full0.32500NoNo-32µMAX/8
CDIP(N)/8
PDIP(N)/8
SOIC(N)/8
MAX491Full0.32500YesYes-32CDIP(N)/14
PDIP(N)/14
SOIC(N)/14
Quality and Environmental Data
Ordering Information
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX481C/DNo Longer AvailableDICE;0°C to +70°CSee data sheet
MAX481CPANo Longer AvailableMAX481CPA+PDIP(N),;8 pin;79.7 mm²0°C to +70°CNo
MAX481CPA+ActivePDIP(N),;8 pin;79.7 mm²0°C to +70°CLead Free
MAX481CSANo Longer AvailableMAX481CSA+SOIC(N),;8 pin;30.9 mm²0°C to +70°CNo
MAX481CSA+ActiveSOIC(N),;8 pin;30.9 mm²0°C to +70°CLead Free
MAX481CSA+TActiveSOIC(N),;8 pin;30.9 mm²0°C to +70°CLead Free
MAX481CSA-TNo Longer AvailableMAX481CSA+TN.SO;8 pin0°C to +70°CSee data sheet
MAX481CUANo Longer AvailableMAX481CUA+µMAX,;8 pin;15.6 mm²0°C to +70°CNo
MAX481CUA+ActiveµMAX,;8 pin;15.6 mm²0°C to +70°CLead Free
MAX481CUA+TActiveuMAX;0°C to +70°CSee data sheet
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX481CUA-TNo Longer AvailableMAX481CUA+TµMAX,;8 pin;15.6 mm²0°C to +70°CNo
MAX481EPANo Longer AvailableMAX481EPA+PDIP(N),;8 pin;79.7 mm²-40°C to +85°CNo
MAX481EPA+ActivePDIP(N),;8 pin;79.7 mm²-40°C to +85°CLead Free
MAX481ESANo Longer AvailableMAX481ESA+SOIC(N),;8 pin;30.9 mm²-40°C to +85°CNo
MAX481ESA+ActiveSOIC(N),;8 pin;30.9 mm²-40°C to +85°CLead Free
MAX481ESA+TActiveSOIC(N),;8 pin;30.9 mm²-40°C to +85°CLead Free
MAX481ESA-TNo Longer AvailableMAX481ESA+TN.SO;8 pin-40°C to +85°CSee data sheet
MAX481MJAActiveCDIP(N),;8 pin;82.6 mm²-55°C to +125°CNo
MAX481MSA/PRNo Longer AvailableMAX481MSA/PR+SOIC(N),;8 pin;30.9 mm²-55°C to +125°CNo
MAX481MSA/PR+ActiveSOIC(N),;8 pin;30.9 mm²-55°C to +125°CLead Free
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX481MSA/PR-TNo Longer AvailableN.SO;-55°C to +125°CSee data sheet
MAX1487-MAX491.pdf MAX491
MAX1487-MAX491_cn.pdf MAX491
Explanation of Maxim RS-485 Features MAX489
MAX481.pdf MAX481
MAX1487-MAX491_cn.pdf MAX491