Clamping window and pulse handling for a 7.78V rail
The 1.5KE9.1CAHA0G: With a 7.78V reverse standoff voltage, this part sits on a nominal 12V battery line without conducting during normal operation. Breakdown starts at 8.65V minimum, and the clamping voltage is held to 13.4V at the 117A peak pulse current (10/1000µs waveform).
Bidirectional channel and package fit
The single bidirectional channel handles both positive and negative transients, which simplifies layout for AC-coupled lines or power rails that see reverse-polarity events. The DO-201AA (DO-27) axial package with through-hole mounting is a standard footprint — the leads are rated for the full 117A pulse without fusing, and the body diameter fits a 1.0mm drill hole on a 2.54mm grid.