3 kW peak pulse power for automotive transient protection
The STMicroelectronics SM30T42AY is a 3 kW peak pulse power (10/1000 µs) TVS diode from the SM30TY TRANSIL™ series, designed to clamp fast transients on automotive power rails. With a 36 V reverse standoff voltage and a 40 V minimum breakdown, it triggers before the protected circuitry sees damaging overvoltage. The clamping voltage is held to 58.1 V at the rated peak pulse current of 48.4 A, which keeps the stress on downstream components within their safe operating area for a 12 V or 24 V automotive bus. AEC-Q101 qualification and the -55°C to 175°C junction temperature range make this part suitable for under-hood, engine bay, and other high-temperature automotive environments where reliability screening is required.
Package and footprint for the BOM
The SM30T42AY is supplied in the DO-214AB (SMC) surface-mount package, a standard footprint for 3 kW-class TVS diodes. The SMC body provides adequate copper area for heat sinking during the pulse event.
This is a standard catalog item from STMicroelectronics, available through independent distribution channels.