20 W flyback with 800 V avalanche-rugged MOSFET
The STMicroelectronics VIPER27HD is a monolithic flyback switching regulator from the VIPer™ plus family, integrating an 800 V avalanche-rugged power MOSFET and a PWM controller in a single 16-SOIC package. It delivers up to 20 W in an isolated flyback topology, switching at 115 kHz with an 80% maximum duty cycle. Built-in fault protections cover current limiting, over-temperature, and over-voltage — the over-voltage protection answers a common design-in question directly.
Supply range and start-up behaviour
The Vcc supply range is 8.5 V to 23.5 V, with a start-up threshold of 14 V. This wide range accommodates the auxiliary winding voltage variation across load and line, simplifying the bias supply design.
The narrow body keeps the footprint compact for dense PCB layouts in adapter and auxiliary supply designs.