What the 1.5SMCJ45A-AQ does in a circuit
The 1.5SMCJ45A-AQ is a unidirectional Zener-based TVS (Transient Voltage Suppressor) — it clamps overvoltage spikes to a defined maximum the moment the standoff threshold is exceeded, protecting downstream electronics from surge events on the line.
Peak pulse handling — what 1.5 kW at 10/1000µs means
A 20.6 A peak pulse current rating at the clamping voltage of 72.7 V is the governing number for selecting the upstream series impedance and verifying the protection circuit's let-through on the load side.
Automotive temperature grade and the SMC package
The DO-214AB (SMC) surface-mount package requires a thermal pad under the body for heat spreading; the cathode tab is the primary heat-dissipation path. Strip packaging means it ships uncut on a tape strip — confirm reel quantities against your assembly line kitting before specifying.
Diotec Semiconductor lists this part as Active. For automotive designs with long production runs, this is the status you want — no forced-migration window to manage.