800V avalanche-rated power stage in a small SSOP-10
The STMicroelectronics VIPER012LS is a monolithic offline switching regulator that integrates an 800V avalanche-rated power MOSFET with a PWM controller in a 10-SSOP package. It delivers up to 7 W in a flyback, buck, or buck-boost topology at a fixed 60 kHz switching frequency.
The 7 W power ceiling places the VIPER012LS in the class of low-power auxiliary supplies: standby power for white goods, bias rails for motor drives, metering power supplies, and IoT gateway PSUs. It is not sized for main converter stages above 7 W — a VIPER013 or VIPER014 (higher current ratings in the same family) would be the next step up if the load budget exceeds 7 W. The 80 % duty cycle limit and 60 kHz switching frequency are typical for a fixed-frequency current-mode controller. The 60 kHz rate keeps the magnetics small enough for a 7 W flyback transformer to fit in an EP7 or EE13 core, while the 80 % duty ceiling sets the minimum input voltage at which the output can be regulated — important for universal AC input (85–265 VAC) designs where the bulk capacitor ripple pulls the DC bus down to around 100 V at light load.
Fault protection set — no external supervisor needed
The VIPER012LS integrates current limiting, over-temperature, over-voltage, and short-circuit protection. The over-voltage protection monitors the Vcc pin and latches off if the auxiliary winding voltage rises above the threshold, which typically happens when the feedback loop opens. The thermal shutdown threshold is set at 150 °C junction temperature, matching the TJ max rating. This protection set means the part can be used in designs that must pass IEC 62368-1 or UL 60950-1 without an external crowbar or supervisory IC.