Transient suppressor for the 40 V automotive bus
The part is rated for 400 W peak pulse power (10/1000 µs waveform), with a reverse standoff voltage of 40 V, a minimum breakdown of 44.4 V, and a clamping voltage of 84 V at the peak pulse current of 27 A (8/20 µs).
400 W pulse rating — what it buys you
For a 40 V nominal rail, the 84 V clamp means the downstream ICs need to survive an 84 V transient for the duration of the pulse. The 27 A peak pulse current rating (8/20 µs) is the current the diode can handle in that shorter waveform — useful for estimating margin against ISO 7637-2 pulses on the automotive 12 V or 24 V bus.