Two-channel iCoupler with 3000Vrms — where it fits the bill
The Analog Devices ADUM1280ARZ is a two-channel, unidirectional digital isolator from the iCoupler series, built around magnetic coupling technology. It provides 3000Vrms of galvanic isolation across a 3V to 5.5V supply range, with both channels on the same side of the isolation barrier (inputs side 1/side 2: 2/0). This makes it a straightforward drop-in for isolating a two-wire digital signal path — think SPI chip-select and clock, UART TX/RX, or a pair of GPIOs — where you need the isolation but not the bidirectional data flow of an isolator with a directional split. At 1Mbps data rate with typical rise/fall times of 2.5ns and a maximum propagation delay of 50ns in either direction, the part handles most sensor readback and control links comfortably. The 25kV/µs minimum common-mode transient immunity (CMTI) is the spec that earns its keep in motor drives, PFC stages, and any environment where a high dV/dt event on the barrier could otherwise glitch the data stream.
3000Vrms isolation and 25kV/µs CMTI — the numbers that decide fit
The 3000Vrms isolation rating is the basic insulation level for this part. For a reinforced-isolation application — medical patient-contact, mains-referenced PSU feedback — you would typically look for a 5000Vrms or higher rated device. But for functional isolation in a 48V telecom brick, a 24V industrial sensor interface, or a gate-drive signal crossing the low-voltage DC bus, 3000Vrms with 25kV/µs CMTI is a solid, cost-effective choice. The 1Mbps data rate means the part is not intended for high-speed isolated SPI (look at the ADuM140x or ADuM144x family for 10Mbps+), but it handles 1MHz clock edges cleanly with 50ns propagation delay. The 10ns maximum pulse-width distortion (PWD) keeps the duty cycle intact across the barrier, which matters for PWM signals or one-wire protocols where edge symmetry is part of the timing budget. Supply range of 3V to 5.5V on both sides means you can run the isolator from the same 3.3V rail as a modern MCU or from a 5V legacy bus without needing a separate regulator or level translator. No isolated power is generated on-chip — the ADUM1280ARZ is a signal isolator only, so each side needs its own local supply and ground reference.