STMicroelectronics – ST485E transceiver draws just 300μA with no load for RS485 and RS422 communication



The ST485E from STMicroelectronics is a low-power transceiver for RS485 and RS422 communication.

The ST485E, which is designed for bi-directional data communications on multi-point bus transmission lines, contains one driver and one receiver in a half-duplex configuration. Each driver output and receiver input is protected against ESD shocks up to ±15kV without latch-up.

The transceiver, which operates from a single 5V supply, draws 300μA when unloaded or fully loaded with disabled drivers.

The driver has short-circuit current limitation, and is protected against excessive power dissipation by thermal shut-down circuitry which puts the outputs into a high-impedance state.

  • Allows up to 256 transceivers on the bus
  • 30ns propagation delay
  • 5ns skew