TVS protection at 22V standoff
The 1.5SMCJ22AS_R1_00001 is a unidirectional Zener-based TVS diode in the DO-214AB (SMC) package, specified 22V reverse standoff with a 1500W peak pulse rating (10/1000µs waveform) — giving a 42.2A peak pulse current before the device enters its defined clamping state. That 22V standoff is the rail voltage the protected line can carry continuously without the TVS conducting; the 24.4V minimum breakdown is where it starts to avalanche and clamp the transient. The 35.5V maximum clamping voltage at peak pulse current is what the downstream IC sees during the event — that figure must stay below the absolute-max rating of whatever is being protected.
What the standoff and clamping specs mean for your design
22V standoff means this part sits cleanly on a 12V or 15V rail without leakage conduction in normal operation — the TVS stays off until a transient exceeds the standoff ceiling. The 24.4V minimum breakdown is the turn-on floor; transients below that level pass without the TVS engaging. Above that threshold the device clamps, and the 35.5V ceiling at 42.2A defines the maximum voltage the protected node ever sees during the event. For a downstream IC with a 30V absolute-max input, the 35.5V clamping ceiling is already tight — confirm the IC's transient withstand rating includes margin above 35.5V, or look for a lower-clamping alternative in the same series footprint.
Thermal and packaging
The DO-214AB (SMC) package is the standard 2-pin surface-mount footprint for this power class; the cathodedot marking identifies the polarity bar on the body. Tape-and-reel packaging suits high-volume assembly runs — confirm the reel quantity matches your pick-and-place magazine depth before committing to volume.