Dual 100 V Schottky in a D²PAK tabbed package
The STPS40SM100CG-TR is a dual common-cathode Schottky rectifier from STMicroelectronics, packing two 20 A, 100 V diodes in a single D²PAK (TO-263) surface-mount package. Each diode is rated for an average rectified current of 20 A with a maximum forward voltage of 810 mV at that current — a reasonable conduction-loss figure for a 100 V Schottky. The pair shares the cathode tab, so the tab is at the output potential in a typical center-tap or OR-ing configuration.
Conduction losses and thermal budget
At 20 A per diode and 810 mV Vf, each die dissipates about 16.2 W in conduction. The D²PAK tab must be soldered to a generous copper plane — the junction temperature ceiling is 150 °C, and the 45 µA reverse leakage at 100 V doubles roughly every 10 °C above 25 °C, so keeping the tab below 110 °C is prudent to avoid thermal runaway in a high-voltage rail.
Obsolete — sourcing via surplus and broker channels
STMicroelectronics lists the STPS40SM100CG-TR as obsolete.