Dual 20 A Schottky in a D2PAK — the conduction loss and thermal budget
The STPS40L45CG-TR pairs two 45 V Schottky diodes in a common-cathode configuration, each rated for 20 A average rectified current. At that full load the forward drop is 530 mV typical — the conduction loss per diode sits at 10.6 W, which the D2PAK's exposed paddle must sink to the board's copper plane. Reverse leakage at 45 V blocking is 600 µA — at high junction temperatures this climbs, so the 150 °C maximum junction rating sets the thermal derating ceiling for continuous operation.
Switching speed and package — what the Fast Recovery spec means for the layout
Rated Fast Recovery under 500 ns at above 200 mA forward current — this is a Schottky, so the recovery is majority-carrier, no stored charge. The 500 ns ceiling covers the tail current during reverse recovery; in practice a 45 V Schottky of this die size recovers in tens of nanoseconds, but the spec guarantees the upper bound for worst-case temperature and current. The D2PAK (TO-263-3) footprint with the exposed tab is the same land pattern as the standard D²Pak. The centre tab is the cathode common node — the PCB copper pour under the tab carries both the thermal path and the output current.
Active lifecycle, ROHS3 — no end-of-life pressure on this BOM line
STMicroelectronics lists the STPS40L45CG-TR as Active with ROHS3 compliance. No NRND flag, no last-time-buy notice. The base product number STPS40 covers the family; the -TR suffix denotes Tape & Reel packaging for automated pick-and-place.