200 V blocking, 4 A forward — the Schottky for the secondary side
The STMicroelectronics STPS4S200B-TR is a 200 V, 4 A Schottky rectifier in a DPAK (TO-252-3) surface-mount package. It is designed for high-frequency output rectification in switch-mode power supplies, freewheeling diodes in DC-DC converters, and reverse-polarity protection circuits where the low forward voltage drop and fast switching of a Schottky barrier are needed. The 200 V reverse voltage rating and 4 A average current rating suit the secondary side of a power supply. The 870 mV forward voltage at 4 A sets the conduction loss floor.
175 °C junction — usable under the bonnet
The ECOPACK® series designation means the device meets ST's lead-free and RoHS-compliant plating specification.