Automotive-grade transient suppressor for 12V/24V vehicle buses
The STMicroelectronics SM30T7.5CAY is a bidirectional Zener TVS diode rated for 3000W peak pulse power (10/1000µs waveform), with a 6.5V reverse standoff voltage and 11.2V clamping point. The single bidirectional channel simplifies layout by eliminating polarity concerns on AC-coupled or floating signal lines.
At 3000W peak pulse power, this part handles the ISO 7637-2 pulse 5a (load dump) on a 12V rail with margin, provided the clamping voltage stays within the downstream device's absolute maximum rating. The 268A peak pulse current at the 10/1000µs waveform tells you the diode can sink a high-energy surge without exceeding the junction temperature limit — useful for direct battery connection where alternator field decay can dump several joules. The 6.5V standoff means the part does not conduct at normal 5V or 3.3V logic levels, but it will start to avalanche at 7.13V minimum breakdown, so it is a fit for protecting 5V-tolerant inputs rather than 3.3V ASICs.
Package and mounting — DO-214AB SMC
Housed in a SMC surface-mount package, the SM30T7.5CAY offers a compact footprint for automated assembly.
Lifecycle and sourcing posture
No LTB or allocation signals are present in the supply chain for this code at this point in the cycle.