4000Vpk isolation for industrial bus isolation
The Texas Instruments ISO7241ADWR is a quad-channel digital isolator using capacitive coupling to pass digital signals across a galvanic isolation barrier rated at 4000Vpk. With a 1Mbps data rate and three forward channels plus one reverse channel (3/1 configuration), it is sized for isolating SPI, UART, or general-purpose logic lines in industrial fieldbus interfaces, motor drive feedback, and PLC I/O modules. The wide supply range from 3.15V to 5.5V lets it bridge 3.3V and 5V logic domains directly, eliminating a separate level translator on the BOM.
25kV/µs CMTI — keeps data clean in noisy environments
Common-mode transient immunity is specified at a minimum 25kV/µs, which means fast-switching edges from a downstream IGBT or MOSFET stage will not glitch the isolated data path. This is the spec that matters when the isolator sits between a controller and a motor-drive power stage or an inverter phase leg. The 95ns max propagation delay (both directions) and 10ns max pulse-width distortion are tight enough for most 1Mbps synchronous serial links, but budget the full 95ns in your timing closure for the return path through the single reverse channel.
The 16-SOIC wide-body package (7.50mm width) provides the creepage distance needed to maintain the 4000Vpk isolation rating across the temperature range. The rise and fall times are a typical 2ns, so the output edges are clean enough to drive a CMOS input without extra Schmitt triggering in most layouts.
Sourcing and lifecycle posture
For dual-sourcing or supply resilience, the ISO7240ADWR is a pin-compatible sibling within the same family — the difference is channel direction mapping (the ISO7240 uses a 4/0 configuration versus the 3/1 here), so verify the directional fit against your bus topology before substituting.