The ADUM3154ARSZ-RL7 is a 4-channel SPI digital isolator from Analog Devices' iCoupler and SPIsolator families, using magnetic coupling to transfer data across a 3750Vrms isolation barrier. Three channels run from Side 1 to Side 2 (SCLK, MOSI, CS), and one channel runs from Side 2 to Side 1 (MISO), matching the standard SPI signal direction. The 2 Mbps data rate limits the SPI clock to roughly 2 MHz — fine for sensor readout, configuration registers, and moderate-throughput ADCs, but not for high-speed serial memory or video links. Propagation delay is 25 ns max, and pulse-width distortion stays under 2 ns, so the clock-to-data skew budget is tight but manageable for most industrial SPI peripherals.
3750Vrms isolation and 25 kV/µs CMTI — industrial and medical barrier
The 3750Vrms isolation rating meets reinforced insulation requirements for many industrial and medical applications. Common-mode transient immunity of 25 kV/µs minimum means the part holds its logic state through fast switching edges on motor drives, inverters, and isolated power supplies — a spec that matters more than the headline isolation voltage when the barrier sees PWM noise.
Rise and fall times are a fast 2.5 ns typical, so keep the trace length short between the isolator and the SPI master or slave to avoid ringing.