What this isolator does on your board
The ADUM1401CRWZ is a 4-channel, unidirectional digital isolator from Analog Devices' iCoupler series, built around magnetic coupling technology rather than the older optocoupler approach. It passes digital signals across a 2500Vrms isolation barrier at up to 90Mbps, with three channels driving from Side 1 to Side 2 and one channel going the reverse direction. The wide-body 16-SOIC package gives the creepage distance needed to maintain the isolation rating across the board.
90 Mbps and 2.5 ns edges — what they mean for signal integrity
The 90Mbps data rate with 2.5ns typical rise and fall times means this part can handle fast serial interfaces like SPI at 20-30 MHz clock rates with clean edges. Propagation delay is 32ns max in either direction, and pulse-width distortion is held to 2ns max — tight enough that duty-cycle-sensitive signals like PWM or Manchester-encoded data pass through without significant skew. The 25kV/µs common-mode transient immunity is the spec that matters when this isolator sits on a motor drive or inverter board: fast-switching IGBTs can slam several thousand volts per microsecond across the barrier, and this part keeps its output state through that transient rather than glitching.
Supply flexibility and temperature range
Supply voltage spans 2.7V to 5.5V on both sides, so you can run the isolated side at a different logic level than the controller side — 3.3V on one side and 5V on the other, for example — without a separate level shifter. No isolated power converter is built in; each side needs its own local supply rail.