Description

The ST485 is al low power transceiver for RS-485 and RS-422 communication. Each part contains

one driver and one receiver. This transceiver draw 300 µA (typ.) of supply current when unloaded or fully loaded with disabled drivers. It operates from a single 5 V supply.

Driver is short-circuit current limited and is protected against excessive power dissipation by

thermal shutdown circuitry that placed the driver outputs into a high-impedance state.

The ST485 is designed for bi-directional data communications on multipoint bus transmission

line (half-duplex applications).

Features

■ Low quiescent current: 300 µA

■ Designed for RS-485 interface application

■ -7 V to 12 V common mode input voltage range

■ Driver maintains high impedance in 3-state or with the power OFF

■ 70 mV typical input hysteresis

■ 30 ns propagation delay, 5 ns skew

■ Operate from a single 5 V supply

■ Current limiting and thermal shutdown for driver overload protection

■ Allows up to 64 transceivers on the bus