1 Mbps, 2500 Vrms, four channels — the industrial isolator that fits the standard slot
The ADUM3401ARWZ-RL is a four-channel, unidirectional digital isolator from Analog Devices' iCoupler magnetic-coupling family. It runs at 1 Mbps with a 2500 Vrms isolation rating, which puts it squarely in the sweet spot for industrial fieldbus isolation — CAN, RS-485, Modbus, and general-purpose SPI isolation where you need three forward channels and one reverse channel (the 3/1 input split on this part). The wide-body 16-SOIC package (7.50 mm body width) gives you the creepage distance for 240 VAC reinforced isolation without moving to a larger footprint.
25 kV/µs CMTI — the spec that keeps the bus clean during a switching event
Common-mode transient immunity is the spec that separates a working isolator from one that glitches when a motor drive or PSU switches. At 25 kV/µs minimum, this part handles the fast common-mode slewing you see in IGBT gate-drive circuits and industrial power stages. The 100 ns max propagation delay (both directions) and 40 ns max pulse-width distortion mean the timing skew across channels stays tight enough for synchronous interfaces like SPI at 1 Mbps.