Isolated RS422/RS485 transceiver with integrated DC-DC
The LTM2881CV-3#PBF from Linear Technology is a complete galvanically isolated RS422/RS485 transceiver in a µModule package. It integrates a magnetic coupling isolation barrier and an isolated DC-DC converter on the output side, so a single 3V to 3.6V supply on the logic side powers both the interface and the isolated bus-side circuitry. The part handles data rates up to 20Mbps and provides 2500Vrms of isolation, with a common-mode transient immunity of 30kV/µs minimum — enough to reject fast transients from motor drives or industrial inverters. The two unidirectional channels (one input on side 1, one output on side 2) are configured for half-duplex RS485 or full-duplex RS422 operation.
At 20Mbps the LTM2881CV-3#PBF keeps the signal edges clean enough for short-haul RS422 links in test equipment, programmable logic controllers, or vision-system interfaces. The 2500Vrms isolation rating covers basic functional isolation for industrial environments where ground loops or voltage differences between equipment racks can exceed the transceiver's common-mode range. The 30kV/µs common-mode transient immunity means the receiver won't glitch when a contactor or VFD switches nearby — a spec that matters more than the headline isolation voltage for noisy-floor installations.
Active production, no end-of-life risk
It is ROHS3 compliant.
