800 V avalanche-rugged power stage in an SO-16
The STMicroelectronics VIPER0PHDTR is an offline switching regulator from the VIPer plus family that integrates an 800 V avalanche-rugged power MOSFET and PWM controller in a 16-SOIC package. It targets auxiliary and bias supplies up to 12 W — think appliance control boards, metering PSUs, and industrial AC-DC rails where board space and BOM count are tight.
120 kHz fixed frequency — transformer sizing
The fixed 120 kHz switching frequency is a practical choice for compact flyback transformers: it keeps the core volume small while staying below the point where snubber losses and EMI filtering start eating the efficiency gain. At 12 W output, a standard RM8 or EFD20 core with the right primary inductance will hit the power target without over-designing the magnetics.
Fault protections that save external parts
On-chip fault protection covers current limiting, over-load, over-temperature, and short circuit — all handled without an external sense resistor or comparator. That means the BOM stays lean: the VIPER0PHDTR can run with just the input bulk cap, startup resistor, transformer, output diode, and a few passives.