12 W offline switcher with integrated 800 V MOSFET
The STMicroelectronics VIPER113LSTR is an offline switching regulator from the VIPER™ series, integrating a power MOSFET and controller in a single 10-SOP package. It delivers up to 12 W in a flyback, buck, or buck-boost topology, switching at 60 kHz with an 80% maximum duty cycle. The integrated MOSFET is rated for 800 V breakdown, giving the part headroom for universal AC input (85–265 VAC) with margin for line transients.
Industrial temperature grade and protection set
On-chip fault protection covers current limiting, over-load, over-voltage, and short-circuit conditions. A soft-start feature reduces inrush stress on the output capacitor and the rectifier during power-up.
The non-isolated output topology (no optocoupler feedback loop) simplifies the BOM and shrinks the board footprint, but the design must account for the primary-referenced output — the load shares the same ground as the switching node.