800 V avalanche-rugged MOSFET with integrated controller
The STMicroelectronics VIPER115XSTR is an off-line high-voltage converter from the VIPER™ family that integrates an 800 V avalanche-rugged power MOSFET with a PWM controller in a single 10-SOP package. It targets non-isolated buck, buck-boost, and flyback topologies up to 12 W output.
Rated 12 W continuous, this part covers auxiliary supplies for appliance control boards, smart meters, and industrial sensor nodes. The 30 kHz fixed switching frequency keeps the transformer and output filter small while staying below the AM radio band. The 80% maximum duty cycle supports wide input-voltage ranges typical of universal AC inputs.
Protection set reduces external component count
Built-in fault protection includes current limiting, overload, overvoltage, and short-circuit — no external sense resistor or OVP comparator needed. Soft-start on the control side limits inrush during start-up. The start-up voltage threshold is 16 V, with the supply range from 4.5 V to 30 V after the auxiliary winding takes over.