22 V Zener, 500 mW — SQ-MELF
The 1N6332US is a 22 V Zener diode in the Microchip SQ-MELF B package, rated for 500 mW continuous power dissipation. The ±5% tolerance on the nominal voltage means the actual Zener voltage falls between 20.9 V and 23.1 V at the specified test current — tight enough for most rail-clamp and reference applications in that band.
Wide-temperature Zener for harsh environments
Operating from -65°C to 175°C, this diode covers the full military temperature range. The SQ-MELF package is a hermetic, surface-mount ceramic barrel — the same construction used in high-reliability and aerospace builds where a plastic SMD package would risk moisture ingress or thermal-cycle fatigue. The 500 mW power ceiling is derated above 25°C; at 175°C the allowable dissipation drops to near zero, so the actual junction temperature under load must be calculated from the thermal resistance of the solder joint and board.