Zener TVS for 12V rail clamping
The 1N6463US/TR is a unidirectional Zener TVS diode from Microchip Technology, designed to clamp transients on a 12V nominal rail. Its 13.6V minimum breakdown voltage and 22.6V maximum clamping at peak pulse current define the protection window — the rail must stay below 12V reverse standoff during normal operation, and the clamp engages when the transient exceeds breakdown.
500W peak pulse and 125A surge capability
Rated for 500W peak pulse power with a 125A peak pulse current under the 8/20µs waveform. The 8/20µs pulse is the standard for lightning surge immunity testing per IEC 61000-4-5 — this diode handles the surge current directly, so the downstream circuitry sees only the clamped voltage. The 10/1000µs waveform is also listed, giving a longer-duration surge reference for telecom port protection.
Active production in SQ-MELF B package
The SQ-MELF B package is a surface-mount ceramic barrel — the same footprint as the standard 1N6463US but supplied on Tape & Reel for pick-and-place assembly. The /TR suffix indicates the reeled format; the bare die and electrical characteristics are identical to the non-reel version.
Wide temperature range for harsh environments
This covers military and industrial extremes — the diode can sit on an outdoor telecom board or inside an engine bay without derating the clamping voltage. The ceramic SQ-MELF package handles the thermal cycling without cracking, unlike molded plastic in the same temperature sweep.