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STMicroelectronics SM30T42CAY — Circuit Protection

SM30T42CAY Automotive TVS Diode, 3000W, AEC-Q101

MPNSM30T42CAY
Active

STMicroelectronics SM30T42CAY, Automotive Grade Zener TVS Diode, Bidirectional, 36V Reverse Standoff, 40V Breakdown (min), 58.1V Clamping (max), 3000W Peak Pulse Power, AEC-Q101 Qualified, DO-214AB (SMC) Package, -55°C to 175°C Junction Temperature.

$1.4100Ref. price · indicative, final on quote
Independent supplier — new & surplus stockAuthenticity-screened · ESD-safe packingListing updated Aug 2026

Specifications

SM30T42CAY specifications
ParameterValue
TypeZener
Series*
MountingSurface Mount
Voltage - breakdown40V
Voltage - clamping (Max) @ ipp58.1V
Voltage - reverse standoff36V
Current - peak pulse (10/1000μs)48.4A
Power - peak pulse3000W (3kW)
Power line protectionNo
Operating temperature-55°C ~ 175°C (TJ)
GradeAutomotive
PackageTape & Reel (TR) Cut Tape (CT)
QualificationAEC-Q101
CaseDO-214AB, SMC
Bidirectional channels1

Product details

What this 36V bidirectional TVS protects — and where it sits

Its 36V reverse standoff voltage fits 24V nominal vehicle power buses, 36V supply rails, and 42V load-dump transients.

Peak pulse power — what 3000W means in a real transient

For a 24V system where load-dump can reach 60V to 80V for several hundred milliseconds, this part absorbs the energy without failing short. The 48.4A peak pulse current at the 58.1V clamp voltage means the protected rail sees a hard voltage ceiling during the surge.

AEC-Q101 qualification and the automotive supply chain

AEC-Q101 qualification means the SM30T42CAY has passed the automotive discrete stress tests: pre- and post-stress electrical parameters, high-temperature reverse bias (HTRB), temperature cycling, and moisture resistance. For a Tier-1 or OEM program, this qualification eliminates the need for additional PPAP-level discrete testing.

Package and footprint — DO-214AB (SMC)

The SMC body fits into the same land pattern as other SMC-packaged TVS diodes. The bidirectional construction means the cathode/anode marking is absent — both directions are identical, simplifying pick-and-place orientation.

Frequently asked questions

Is SM30T42CAY AEC-Q101 qualified?

Yes, the SM30T42CAY is AEC-Q101 qualified, making it released for automotive production programs without additional discrete-level qualification testing.