1.5 kW pulse in a DO-201 body
The 1.5KE400A/B: That 1.5 kW rating means it absorbs a single transient up to that energy without failing — a 342 V reverse standoff voltage means the protected rail sits below the clamping threshold during normal operation, and the diode only conducts when the transient exceeds 380 V breakdown. The 548 V clamping voltage at 2.8 A peak pulse current is the ceiling the diode holds the transient to — downstream components see no more than that, which is the number to check against the absolute maximum ratings of the ICs or modules on the rail.
The DO-201AA (DO-27) axial package is a standard leaded form factor that fits existing PCB layouts for the 1.5KE family.
Sourcing and compliance
No power line protection (the diode is not designed for AC mains primary-side clamping), but for DC rails, signal lines, and secondary-side transient suppression at 342 V working voltage, this is a standard fit.