4000 Vpk isolation in an 8-SOIC — what it buys the BOM
The TI ISO7221AQDRQ1 is a two-channel, unidirectional digital isolator using capacitive coupling to deliver 4000 Vpk galvanic isolation in a standard 8-SOIC footprint. The 1 Mbps data rate is a deliberate choice — enough for CAN, LIN, and SPI isolation without the cost and EMI of a 25 Mbps or 150 Mbps part.
25 kV/µs CMTI — the spec that matters in a noisy environment
That is the spec that keeps the data path clean when a motor drive or an inverter switches a high-voltage rail — if the CMTI is too low, the isolator can glitch and corrupt the signal. At 25 kV/µs this part handles the sort of transient slew rates you see in automotive traction inverters and industrial servo drives. The propagation delay is 480 ns max in both directions, with a pulse-width distortion of 14 ns max — tight enough for a 1 Mbps signal but not a fit for a high-speed SPI bus running at 10 MHz.
The ROHS3 compliance and AEC-Q100 qualification are already baked in, so no separate qualification paperwork is needed for automotive projects.
Package and supply — what the layout engineer sees
Surface-mount in the 8-SOIC (3.90 mm width) package, with the supplier device package also listed as 8-SOIC. That keeps the board area tight: just the isolator, two bypass caps, and the series resistors on the output side if the load demands it.