SPI isolator with 34 Mbps throughput and 5000 Vrms barrier
The Analog Devices ADUM4154BRIZ is a 4-channel SPI digital isolator from the iCoupler and SPIsolator families, built on magnetic coupling technology. It is designed to isolate SPI buses in systems requiring galvanic isolation up to 5000 Vrms while passing data at 34 Mbps — fast enough for most multi-MHz SPI peripherals without adding a clock-cycle penalty. The channel configuration is 3 inputs on side 1 and 1 input on side 2, matching the typical SPI signal set (SCLK, MOSI, CS, MISO). Propagation delay is 14 ns max, and pulse-width distortion stays under 2 ns, so the clock-to-data skew budget remains tight enough for back-to-back 34 Mbps frames.
Supply range and logic compatibility
The unidirectional channel type matches the SPI bus direction — each channel drives one way, so the isolator itself handles the level translation. Rise and fall times are 2.5 ns typical, keeping edge rates fast enough for 34 Mbps but not so fast that they cause excessive EMI without some series termination on long traces.
Industrial temperature and isolation for harsh environments
The 5000 Vrms isolation rating, combined with 25 kV/µs minimum common-mode transient immunity, means it can sit on a gate-driver or inverter control board without losing data during fast-switching events. The 20-SOIC wide-body (7.50 mm width) package provides the creepage distance needed to maintain the isolation rating across the PCB.
