TransZorb Zener TVS — 1500W axial clamp
The 1.5KE9.1A-E3/51: Its 7.78V reverse standoff voltage protects 5V and 3.3V rails from transients, clamping at 13.4V maximum when the 112A peak pulse current flows. The DO-201AA axial-lead package handles the thermal pulse — the 1500W rating is the energy it can absorb in a single surge without failing.
Stock is sourced through independent and surplus distribution; quantities and pricing are confirmed at RFQ.
Electrical limits and temperature envelope
Breakdown voltage starts at 8.65V minimum, so a 7.78V rail sees no leakage at nominal voltage — the diode stays off until the transient pushes past the threshold. No power-line protection feature (internal crowbar or SCR) — this is a pure Zener clamp, not a thyristor-based suppressor.
Package and rework on the bench
The DO-201AA axial body is through-hole — the leads are 0.96 mm diameter and the body is 5.3 mm diameter, so it fits standard 1.0 mm PCB holes. Axial diodes are easy to hand-replace with a soldering iron or hot-air station; the leads are long enough to dress into the board without stressing the glass passivation.