75 V, 300 mA fast recovery in a hermetic SQ-MELF
The Microchip Technology 1N6640US is a fast recovery diode rated for 75 V DC reverse voltage and 300 mA average rectified current, with a 4 ns reverse recovery time that places it well inside the Fast Recovery classification (≤500 ns at >200 mA). The SQ-MELF (D-5D) surface-mount package is a hermetic, ceramic-bodied cylindrical case designed for high-reliability and aerospace applications where moisture resistance and thermal cycling survivability are required.
Junction temperature range and leakage profile
The -65°C to 175°C junction temperature range covers the full military/aerospace thermal envelope — the 175°C upper limit allows operation in engine-bay or down-hole environments where commercial-grade diodes would fail. Forward voltage is 1 V maximum at 200 mA forward current — the 0.2 W conduction loss at rated current is manageable within the SQ-MELF's thermal impedance, but derating is required above 125°C case temperature.