200 V, 4 A Schottky — the rating that defines the rectifier
The STPS4S200UF is a 200 V, 4 A Schottky rectifier from STMicroelectronics, housed in the low-profile SMBflat (DO-221AA) surface-mount package. It is part of the ECOPACK® series, which means the package materials meet RoHS and halogen-free requirements. Typical applications include freewheeling diodes in power supplies, OR-ing circuits, and polarity protection in automotive and industrial systems where the 175°C junction temperature rating allows operation in hot environments like engine compartments or sealed enclosures.
At 4 A forward current, the maximum forward voltage is 870 mV. That is a relatively low Vf for a 200 V Schottky, which keeps conduction losses manageable in a 4 A load path. Reverse leakage is specified at 5 µA at the full 200 V reverse voltage — low enough to avoid significant standby dissipation in continuously biased OR-ing or reverse-protection circuits.
Junction temperature range — rated for harsh environments
That 175°C upper limit is a key differentiator — many Schottky rectifiers in this voltage/current class top out at 150°C. The extra headroom matters in designs where the diode sits near hot power magnetics or in ambient temperatures above 85°C, such as industrial power supplies or under-hood automotive modules.
SMBflat package — footprint and assembly
The SMBflat package (DO-221AA) is a surface-mount, flat-lead design with a low profile. It uses standard SMB footprint land patterns, so it drops onto existing board layouts without re-spinning the PCB. The flat leads improve solder joint reliability under thermal cycling compared to traditional J-bend or gull-wing leads.
The base product number is STPS4, and the 'UF' suffix indicates the SMBflat package variant.
This part is ROHS3 compliant and is qualified under ST's ECOPACK® initiative.