This surface mount Zener Voltage Regulator series is military qualified to MIL-PRF-19500/356 and is ideal for high-reliability applications where a failure cannot be tolerated. These industry-recognized 5 Watt Zener Voltage Regulators are hermetically sealed with voidless-glass construction using an internal metallurgical bond. It includes Zener selections from 3.3 to 390 volts in standard 5% tolerances as well as tighter tolerances identified by different suffix letters on the part number. They are also available in axial-leaded packages for thru hole mounting by deleting the "US" suffix (see separate data sheet for 1N4954 thru 1N4996, 1N5968 thru 1N5969, and 1N6632 thru 1N6637). Microchip also offers numerous other Zener products to meet higher and lower power ratings in both thru-hole and surface mount packages.