What the 400W peak pulse rating means for your protection budget
The SMAJ45A-13: For a 45V rail, the 400W rating translates to a 5.5A peak pulse current capability, which covers most industrial signal-line and low-power DC bus transients from inductive load switching or ESD events. The 72.7V maximum clamping voltage at that 5.5A peak current is the voltage the downstream circuitry actually sees during a surge. A lower clamp voltage means better protection margin for sensitive ICs on the 45V rail — the designer should verify that the protected components have an absolute maximum rating above 72.7V.
Active lifecycle — no last-time-buy pressure
The part is supplied in Tape & Reel packaging (standard for DO-214AC SMA), which is the dominant format for automated SMT assembly. Reel quantity and pricing tiers are confirmed at quote time against the specific BOM volume.
Package and temperature grade — board-fit and environment check
Housed in the DO-214AC (SMA) surface-mount package, the SMAJ45A-13 uses the standard JEDEC footprint for 400W TVS diodes. The operating temperature range spans -55°C to 150°C (junction). This covers the full industrial temperature envelope plus margin into military/aerospace applications. The wide range means the TVS maintains its clamping characteristics across cold-start conditions and hot engine-bay environments alike.
Sourcing and supply posture
As an active, standard-catalog part from Diodes Incorporated, it does not carry the supply constraints of a sole-sourced or allocation-prone line. The 400W SMAJ family is widely second-sourced across multiple manufacturers, providing additional BOM hedge options if needed.