1500W automotive transient suppressor
The STMicroelectronics SM15T15AY is a unidirectional Zener TVS diode rated for 1500W peak pulse power, designed to clamp transients on 12V automotive power rails. It offers a 12.8V reverse standoff voltage, a minimum breakdown of 14.3V, and a maximum clamping voltage of 27.2V at the peak pulse current of 368A (8/20µs waveform).
Clamp voltage and rail protection
The 27.2V clamp voltage at 368A peak pulse current is the key parameter for verifying that downstream 40V-rated DC-DC converters or ASICs survive a load-dump event. With a 12.8V standoff, this part sits on a nominal 12V battery line without conducting leakage in normal operation. The 14.3V minimum breakdown provides a guard band against sustained overvoltage from an alternator regulator failure.
AEC-Q101 and the automotive BOM
AEC-Q101 qualification means the SM15T15AY has passed the automotive-grade stress tests: high-temperature reverse bias, temperature cycling, and humidity. This is the baseline for any Tier-1 or OEM BOM that requires PPAP-level documentation.
SMC package and board fit
Housed in the DO-214AB (SMC) package, this surface-mount TVS offers a compact footprint for automated assembly. The SMC body handles the 1500W pulse without requiring a heatsink, relying on the PCB copper pour for thermal dissipation. The package is compatible with standard reflow profiles; MSL rating should be verified from the label for bake requirements before reflow.