The SMAJ5.0CA-13-F: That 400 W figure is the energy-handling ceiling for a single transient event — a 43.5 A peak current clamped to 9.2 V means the part absorbs the surge without letting the protected rail exceed the clamping voltage.
Trigger and hold-off voltages
Reverse standoff voltage is 5 V — the TVS stays transparent below this level, so a 5 V supply rail sees no leakage impact during normal operation. Breakdown triggers at 6.4 V minimum, and clamping hits 9.2 V at the rated peak current. That 4.2 V window between standoff and clamp gives the designer margin for supply ripple and tolerance without false triggering.
Package and field-swap reality
Housed in a DO-214AC (SMA) surface-mount package, the part is a standard footprint for rework — a hot-air station or even a soldering iron with a fine tip can swap it on site if the board has adequate pad access. The SMA body is small enough for dense layouts but large enough to read the marking without magnification.