10V zener in a hermetic SQ-MELF — the scorch mark tells you
The 1N6324US/TR is a 10 V zener diode from Microchip Technology, qualified to MIL-PRF-19500/533 and rated for 500 mW continuous power dissipation in the SQ-MELF B package. The -65°C to +175°C junction temperature range matches the military-grade thermal envelope — this part survives the temperature swings you see in avionics, satellite, and downhole equipment where a commercial plastic-packaged zener would fail from thermal cycling fatigue. At 6 Ohms maximum zener impedance, the regulation slope is tight enough that a 10 mA load step shifts the output less than 60 mV — relevant if you are using this as a shunt reference in a precision bias supply.
SQ-MELF footprint — what the rework bench needs to know
The SQ-MELF B package is a hermetic surface-mount ceramic body with metallized end caps — no molded plastic, no moisture sensitivity level (MSL) concern, no bake-out required before reflow. The body absorbs essentially zero moisture, so you can pull it from a tape reel and run it through a 260°C peak profile without popcorning risk. The 1.4 V forward voltage at 1 A forward current is not the primary operating mode for a zener, but it tells you the die size and bond-wire construction can handle brief forward surges during reverse-battery events or inductive kickback clamping.