170 V Schottky in an SMAflat package — where this part sits
The STPS1170AFN is a 170 V, 1 A Schottky rectifier from STMicroelectronics, housed in the low-profile DO-221AC (SMA Flat Leads) package.
Forward drop and reverse leakage — the efficiency trade
At 1 A forward current the maximum forward voltage is 820 mV, and reverse leakage at the 170 V rated voltage is 1.5 µA. That 820 mV Vf is higher than a low-Vf 40 V Schottky but expected for a 170 V part — the voltage rating costs you some forward efficiency. The 1.5 µA leakage at full reverse bias is low enough that it won't dominate standby losses in most circuits, but if your design idles at 170 V reverse for long periods, derate for temperature: leakage doubles roughly every 10°C above 25°C junction.
Package and mounting — SMAflat footprint note
The SMA Flat Leads package (DO-221AC) is a surface-mount form factor with a lower profile than standard SMA. The supplier device package is called SMAflat. It's compatible with standard SMA solder pads but the lead shape is different — verify the land pattern in the datasheet if you're migrating from a conventional SMA. The part ships on Tape & Reel, which is the usual for automated pick-and-place.
The part is part of the ECOPACK2 series, meaning it meets ST's halogen-free and antimony-free material declaration for RoHS compliance. No AEC-Q101 qualification is listed in the record, so it's not formally automotive-grade — stick to industrial, telecom, and consumer applications unless you run your own qualification.