The 1.5SMC33AHM6G: That 1500 W rating means it can clamp a 34 A surge to 45.7 V without failing — the energy is absorbed in the silicon junction, not passed downstream to the load. Breakdown starts at 31.4 V minimum, giving a guard band for a 24 V nominal automotive bus that sees transients up to the 28 V load-dump ceiling.
Automotive qualification and temperature range
AEC-Q101 qualification means this part passed the automotive stress tests: high-temperature reverse bias, temperature cycling, and ESD robustness. The part is unidirectional (one channel), so polarity matters: the cathode band on the package must face the rail being protected.