Zener TVS diode for 62.2 V rail protection
Its 500 W peak pulse power rating gives it the energy capacity for industrial control, telecom, and power-supply secondary-side protection where the line sees repetitive surges. With a minimum breakdown voltage of 77.9 V and a maximum clamping voltage of 112.8 V at 4.4 A peak pulse current, this part leaves a comfortable margin above the 62.2 V standoff — the rail never sees the clamp engage during normal operation.
Bidirectional channel and wide temperature envelope
The through-hole axial package (B, Axial per the supplier device code) suits point-to-point wiring on terminal strips or PCB layouts where a TO-220 or surface-mount part would complicate the thermal path. No power line protection feature is claimed — this is a pure transient clamp, not a filter.
Microchip lists the 1N6128A as Active, so no end-of-life notice is pending. The base product number is 1N6128, and the full order code includes the 'A' suffix for the specific breakdown tolerance bin.