MAX1480B:Complete, Isolated RS-485/RS-422 Data Interface

The MAX1480A/MAX1480B/MAX1480C/MAX1490A/MAX1490B are complete, electrically isolated, RS-485/RS-422 data-communications interface solutions in a hybrid microcircuit. Transceivers, optocouplers, and a transformer provide a complete interface in a standard DIP package. A single +5V supply on the logic side powers both sides of the interface. The MAX1480B/MAX1480C/MAX1490B feature reduced-slew-rate drivers that minimize EMI and reduce reflections caused by improperly terminated cables, allowing error-free data transmission at data rates up to 250kbps. The MAX1480A/MAX1490A driver slew rate is not limited, allowing transmission rates up to 2.5Mbps. The MAX1480A/B/C are designed for half-duplex communication, while the MAX1490A/B feature full-duplex communication. Drivers are short-circuit current limited and 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 known output (active-low RO low for the MAX1480A/B/C, RO high for the MAX1490A/B) if the input is open circuit. The MAX1480A/MAX1480B/MAX1480C/MAX1490A/MAX1490B typically withstand 1600VRMS (1 minute) or 2000VRMS (1 second). Their isolated outputs meet all RS-485/RS-422 specifications. The MAX1480A/B/C are available in a 28-pin DIP package, and the MAX1490A/B are available in a 24-pin DIP package.

Key Features
  • For Integrated ESD Protection
    • MAX1480E/MAX1490E: ±15kV ESD-Protected, Isolated RS-485/RS-422 Data Interfaces
  • For Space-Constrained Applications
    • MAX3157: High CMRR, RS-485 Transceiver with ±50V Isolation
MAX1490A, MAX1490B: Pin Configuration
MAX1490A, MAX1490B: Pin Configuration
Applications/Uses
  • Automated Test Equipment (ATE)
  • HVAC/Building Control Networks
  • Industrial-Control Local Area Networks
  • Isolated RS-485/RS-422 Data Interface
  • Transceivers for EMI-Sensitive Applications
DataSheet
titleDownload file
MAX1480A-MAX1490B Data SheetMAX1480A-MAX1490B.pdf
Parametrics
Part NumberTx/RxDuplexVSUPPLY
(V)
Galvanic Isolation
(±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
MAX1480A1Tx + 1RxHalf51000602500YesNo0.2128OpenNo-40 to +85
0 to +70
PDIP(W)/28$19.19 @1k
MAX1480BHalf35250Yes128PDIP(W)/28$14.66 @1k
MAX1480CHalf35250Yes128PDIP(W)/28$14.66 @1k
MAX1490AFull1002500No32PDIP(W)/24$19.18 @1k
MAX1490BFull65250No32PDIP(W)/24$14.67 @1k
Quality and Environmental Data
Ordering Information
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX1480BCPINo Longer AvailableMAX1480BCPI+PDIP(W),;28 pin;592.6 mm²0°C to +70°CNo
MAX1480BCPI+ActivePDIP(W),;28 pin;592.6 mm²0°C to +70°CSee data sheet
MAX1480BEPINo Longer AvailableMAX1480BEPI+PDIP(W),;28 pin;592.6 mm²-40°C to +85°CNo
MAX1480BEPI+ActivePDIP(W),;28 pin;592.6 mm²-40°C to +85°CSee data sheet
MAX1480A-MAX1490B.pdf MAX1490B
MAX1480A-MAX1490B_cn.pdf MAX1490B
RS-485 Data Interface Gives Isolated, Full-Duplex Operation MAX485E
MAX1480B.pdf MAX1480B
MAX1480A-MAX1490B_cn.pdf MAX1490B