30 A, 120 V Schottky — obsolete, but still spec'd into power designs
The STPS30SM120ST is a 30 A, 120 V Schottky rectifier from STMicroelectronics in a through-hole TO-220-3 package. The forward voltage drop is 950 mV maximum at 30 A, which sets the conduction loss at full load. This is a key input for the thermal budget when heatsinking the TO-220 tab.
The part carries the ECOPACK2 series designation, indicating ST's lead-free and RoHS-compliant package finish. No AEC-Q automotive qualification is listed in the record.
Reverse leakage and junction temperature limits
Reverse leakage current is 275 µA at the rated 120 V reverse voltage. The maximum junction temperature is 150°C, which is the ceiling for the TO-220 package's thermal performance when bolted to a heatsink.