Transient suppression in a SQ-MELF body
The 1N6158AUS: The SQ-MELF (C) package is a surface-mount ceramic body that handles the thermal pulse of a 23.2A peak current without cracking — a common failure mode in plastic SMD packages under repetitive surge.
Minimum breakdown is 44.7V, clamping at 64.6V max — a 44% headroom above the 35.8V standoff. That margin keeps the protected rail below the absolute-max rating of most 48V bus transceivers and 40V-rated DC-DC converters during a surge event.
The SQ-MELF package also offers lower thermal resistance than a comparable SMB/SMC plastic body, which helps keep junction temperature in check during sustained clamping.
The SQ-MELF package is a standard Microchip offering, so lead times typically track the broader TVS product line.