The 1.5SMC22CAH: This is a single-channel bidirectional device — it clamps transients of either polarity, so no orientation decision on the PCB.
Automotive grade and temperature range
The AEC-Q101 stamp means the part passed the full suite of accelerated life tests (HTRB, H3TRB, autoclave, temperature cycling) that commercial-grade parts skip. At 150°C junction, the leakage current and clamping voltage shift per the datasheet derating curve — budget the 1500W peak pulse at 25°C to derate linearly to zero at 150°C.