Zener TVS for automotive transient protection
The P6SMB47CAT3 is a bidirectional Zener transient-voltage-suppression diode from onsemi, part of the Automotive series with AEC-Q101 qualification.
Clamping and breakdown margins
Breakdown voltage min is 44.7V, giving a 4.5V guard band above the 40.2V standoff — enough to ride through normal rail ripple without nuisance triggering. The 64.8V clamp ceiling limits the voltage seen by downstream silicon, and the 9.3A peak pulse current rating (10/1000µs) defines the surge it can absorb before the junction overheats. Capacitance is 220pF at 1MHz, which is moderate — suitable for low-speed signal lines or power rails, but may load high-frequency data buses beyond a few MHz.
onsemi has marked the P6SMB47CAT3 as Obsolete. For BOM sustainment, buyers should plan for last-time buys or identify a form-fit-function replacement from the same P6SMB family (base product number P6SMB) with matching voltage and bidirectional configuration.