400W bidirectional TVS for 12V automotive rails
The SMAJ12CAQ-13-F: It clamps a 12V nominal rail at 19.9V maximum, with a breakdown voltage of 13.3V minimum.
With a 19.9V maximum clamping voltage at 20.1A peak pulse current, the TVS holds a 12V supply bus below the typical 24V abs-max of downstream ICs. The 400W rating is the peak pulse power at the 10/1000µs test waveform — a shorter pulse (e.g. 8/20µs) allows higher peak current before the device reaches its thermal limit. The bidirectional channel (single device) protects signal pairs or power rails that swing both sides of ground — no need to orient the diode or worry about reverse insertion.