10 W flyback with an 800 V internal MOSFET
The VIPER17HN is an offline flyback converter from ST's VIPer™ plus family, integrating an 800 V power MOSFET and a 115 kHz fixed-frequency PWM controller in a single 8-DIP through-hole package. It delivers up to 10 W of isolated output power — enough for auxiliary supplies in appliance, industrial, or IoT gateway power stages. The 800 V breakdown voltage gives headroom for universal AC input without an external clamping circuit, simplifying the primary-side layout.
Sizing the supply around the 10 W ceiling
The 10 W power rating is the continuous output capability at the nominal input voltage and ambient temperature — actual deliverable power depends on the transformer design, heatsinking, and the 70% maximum duty cycle. The 8.5 V to 23.5 V Vcc range allows the IC to run directly from an auxiliary winding or a small bias supply, and the 14 V start-up threshold ensures clean turn-on without external start-up resistors. Fault protection includes current limiting, over-temperature shutdown, and over-voltage lockout, which together prevent the supply from running into destructive failure modes during a load fault or a transformer saturation event.
It is ROHS3 compliant and supplied in a standard Tube — the 8-DIP (0.300", 7.62 mm) through-hole package is a common footprint that can be hand-soldered or wave-soldered without reflow profile concerns.