The STMicroelectronics SM6T56AY is a 600 W peak pulse power TVS diode from the automotive-grade SM6TY TRANSIL™ series, qualified to AEC-Q101. It is a unidirectional Zener-type transient suppressor in a surface-mount DO-214AA (SMB) package, designed to clamp fast overvoltage transients on 47.6 V nominal supply rails. The 53.2 V minimum breakdown voltage and 100 V maximum clamping voltage define the protection window for a 40 A (8/20 µs) peak pulse current.
AEC-Q101 qualification and active lifecycle
Clamping voltage and protection window
When a transient exceeds the 53.2 V minimum breakdown voltage, the diode avalanches and clamps the voltage to a maximum of 100 V at the rated 40 A peak pulse current (8/20 µs waveform). This 100 V clamp is the voltage the downstream circuitry must survive; a 60 V-rated DC-DC converter or 80 V-rated load switch would need additional margin or a lower-clamp part.
Package and footprint for DO-214AA SMB
The SM6T56AY is supplied in a DO-214AA (SMB) package, a standard surface-mount outline for TVS diodes rated to 600 W. The SMB footprint is shared across the SM6TY series, so a layout designed for one breakdown voltage can accept any voltage variant in the family without board revision.