25 Mbps capacitive isolator for industrial signal isolation
The Texas Instruments ISO7241CDW is a 4-channel, unidirectional digital isolator using capacitive coupling to provide galvanic isolation up to 2500 Vrms. It supports a data rate of 25 Mbps with typical rise/fall times of 2 ns and a maximum propagation delay of 42 ns in either direction. The 3/1 channel split (three inputs on side 1, one on side 2) suits asymmetric interfaces like SPI or UART where the main data flow is one way.
Package and mounting
The 2500 Vrms isolation rating is the basic safety isolation level for industrial equipment — motor drives, PLC I/O modules, and power supplies — where the isolator must prevent ground loops and protect low-voltage logic from transient voltages on the field side. The 25 kV/µs common-mode transient immunity (CMTI) means the part can reject fast voltage spikes common in inverter-driven environments without corrupting the data stream. For a 25 Mbps signal with 42 ns propagation delay, the pulse-width distortion is held to 2.5 ns maximum, keeping the duty cycle close to 50% through the isolation barrier.
Industrial temperature range and wide-body SOIC
Surface-mount assembly is standard; no isolated power is integrated, so the design must supply separate power domains on each side of the barrier.
If a second-source option is needed, the ISO7241 family includes pin-compatible variants with different channel configurations — the base product number ISO7241 spans the same package and isolation rating.