The STTH9012TV2 is a dual fast-recovery epitaxial diode from STMicroelectronics, rated for 1200 V reverse voltage and 45 A average forward current per diode in a 2-independent configuration. The 125 ns reverse recovery time (trr) at 1200 V places it in the fast-recovery class for high-voltage rectification and freewheeling applications — think output rectifiers in 400 VAC input SMPS, boost diodes in power-factor-correction stages, and clamp diodes in motor-drive inverters. The 2.1 V forward drop at 45 A sets the conduction loss budget per leg at roughly 95 W, so the ISOTOP chassis-mount package is sized for bolting to a heatsink with the right thermal interface. Junction temperature maxes at 150 °C, which is the derating ceiling for the thermal stack.
ISOTOP footprint — mounting and thermal design
The ISOTOP® package (also known as ISOTOP) is a standard 4-pin power module with M4 screw terminals for chassis mounting. Two independent diode die share the same baseplate; the cathode of each diode is electrically isolated from the mounting base, so a single heatsink can be common across both legs without insulation pads. The 30 µA reverse leakage at 1200 V is a room-temperature typical — expect leakage to double roughly every 10 °C above 25 °C junction, so budget for it in the bias network at high-temperature operation.
STMicroelectronics lists the STTH9012TV2 as Active.