1.5kW Zener TVS in DO-214AB — what the ratings mean for the BOM
The 1.5SMC18AHE3/57T: It clamps at 25.2 V max with a peak pulse current of 59.5 A, and its 15.3 V reverse standoff means it stays out of the circuit until the transient exceeds that threshold — so a 12 V or 15 V rail sees no leakage under normal operation. AEC-Q101 qualification and a -65°C to 150°C junction temperature range put this part in the under-hood / engine-bay deployment class — the thermal margin covers the 105°C ambient a summer-grade ECU sees, plus the self-heating from repetitive pulses.
DO-214AB (SMC) surface-mount package, also designated as SMCJ by the supplier device code.
No official successor or pin-compatible cross-reference is documented — the 1.5SMC18AHE3/57T is the current production order code for this voltage and package variant.