Schottky rectifier for low-voltage DC rails
The STPS2L40AFN is a 2 A, 40 V Schottky rectifier diode from STMicroelectronics, designed for low forward-voltage drop in power supply and polarity-protection circuits. Its 430 mV typical forward drop at 2 A keeps conduction losses low in moderate-current DC rails.
Package and mounting — SMAflat for tight boards
Housed in the DO-221AC (SMA Flat Leads) package, the STPS2L40AFN is a surface-mount device with a low-profile body suited for dense PCB layouts. The flat-lead design reduces board height compared to standard SMA packages, which helps in slim enclosures.
Reverse leakage and junction temperature limits
Reverse leakage is specified at 220 µA at the full 40 V reverse voltage. The maximum junction temperature is 150 °C, which sets the thermal derating boundary for continuous operation. In a 2 A rectifier application, the low Vf helps keep the junction temperature within limits, but the leakage current rises with temperature — a consideration for high-ambient or poorly vented enclosures.