The MAX481E, MAX483E, MAX485E, MAX487E-MAX491E, and MAX1487E are low-power transceivers forRS-485 and RS-422 communications in harsh environments.Each driver output and receiver input is protectedagainst ±15kV electro-static discharge (ESD) shocks,without latchup. These parts contain one driver and onereceiver. The MAX483E, MAX487E, MAX488E, andMAX489E feature reduced slew-rate drivers that minimizeEMI and reduce reflections caused by improperly terminatedcables, thus allowing error-free data transmissionup to 250kbps. The driver slew rates of the MAX481E,MAX485E, MAX490E, MAX491E, and MAX1487E are notlimited, allowing them to transmit up to 2.5Mbps.

These transceivers draw as little as 120µA supply currentwhen unloaded or when fully loaded with disableddrivers (see Selector Guide). Additionally, the MAX481E,MAX483E, and MAX487E have a low-current shutdownmode in which they consume only 0.5µA. All parts operatefrom a single +5V supply.

Drivers are short-circuit current limited, and are protectedagainst excessive power dissipation by thermal shutdowncircuitry that places their outputs into a high-impedancestate. The receiver input has a fail-safe feature that guaranteesa logic-high output if the input is open circuit.

The MAX487E and MAX1487E feature quarter-unit-loadreceiver input impedance, allowing up to 128 transceiverson the bus. The MAX488E-MAX491E aredesigned for full-duplex communications, while theMAX481E, MAX483E, MAX485E, MAX487E, andMAX1487E are designed for half-duplex applications.For applications that are not ESD sensitive see the pinandfunction-compatible MAX481, MAX483, MAX485,MAX487-MAX491, and MAX1487.