Hermetic rectifier for high-reliability circuits
The 1N649UR-1 is a standard recovery rectifier diode from Microchip Technology, rated for 400 mA average rectified current with a 600 V reverse voltage maximum. The 1 V forward voltage drop at 400 mA is typical for a standard recovery device in this current class, and the 50 nA reverse leakage at 600 V indicates a clean junction that holds off rated voltage in high-impedance bias circuits. The DO-213AA hermetic glass package gives this part a sealed cavity that resists moisture ingress and outgassing, making it a candidate for avionics, satellite, and downhole applications where a plastic-molded diode would be excluded by the environmental specification.
Temperature grade and junction rating
The junction is rated for -65 °C to +175 °C, covering the full military temperature band. At the 175 °C upper limit the reverse leakage will have increased above the 25 °C figure, but the hermetic package prevents the moisture-related failure mechanisms that plague plastic-packaged diodes above 150 °C.