The STMicroelectronics STPS1H100MF is a 100 V, 1 A Schottky barrier rectifier in the DO-222AA STmite Flat package. It is designed for high-frequency DC-DC converter secondary-side rectification, freewheeling diodes in switching supplies, and reverse polarity protection circuits where low forward voltage drop and fast switching are needed.
At 1 A forward current the STPS1H100MF drops 770 mV typical. That figure drives the conduction loss and junction temperature rise in the application. For a 1 A load the dissipation is about 770 mW — manageable in the STmite Flat package if the PCB copper area is adequate. If your design runs at 0.5 A or below the drop will be lower, improving efficiency further. Compare this to a standard PN-junction rectifier that might drop 1.1 V at the same current — the Schottky saves roughly 330 mW per amp, which adds up in a multi-output supply.
Package and rework: STmite Flat
The DO-222AA STmite Flat is a small, low-profile surface-mount package. It is rework-friendly under a hot-air station if you have a fine nozzle and steady hands — the body is small, so alignment matters. Pin 1 orientation is marked on the package body. The flat leads have good solder wetting; just keep the hot-air temperature under 350°C and preheat the board to avoid thermal shock. The package is MSL 1 per typical ST Schottky handling, so no bake required before reflow if the bag seal is intact.
That means no last-time-buy clock is running, and the part is in normal production through ST's distribution channel. For a BOM line this translates to predictable supply and no forced redesign.