What the 1500W rating means for a 24V rail
The 1.5SMC24AT3 is a unidirectional Zener TVS diode rated for 1500W peak pulse power (10/1000µs waveform) with a reverse standoff voltage of 20.5V and a clamping voltage of 33.2V at 45A peak pulse current. This part is designed to clamp transients on a nominal 24V DC bus — the 20.5V standoff keeps leakage negligible under normal operation, while the 33.2V clamp protects downstream components from surges up to 45A.
Obsolete — plan your BOM move now
onsemi has marked the 1.5SMC24AT3 as Obsolete. For a production BOM, you need to secure remaining stock or qualify a replacement. The DO-214AB SMC footprint is shared by many TVS diodes in the 1.5SMC series — a drop-in alternative with the same 1500W rating and 20.5V standoff can be sourced, but confirm the clamping voltage and peak current match your surge requirement.
Package and mounting for PCB fit
Surface-mount SMC package, supplied in Tape & Reel or Cut Tape. The SMC body is larger than the SMA/SMB siblings — ensure your PCB land pattern matches the JEDEC standard for DO-214AB. Operating junction temperature range is -65°C to 150°C, covering industrial and automotive underhood environments.