Description
The STEVAL-ISA111V1 demonstration board is a
12 V, 1 A power supply set in non-isolated flyback
topology using the VIPER26HN, the new offline
high voltage converter by STMicroelectronics.
The features include an 800 V avalanche rugged
power section, PWM operation at 115 kHz with
frequency jittering for lower EMI, current limiting
with adjustable set point, onboard soft-start, a
safe auto-restart after a fault condition and a low
standby power. The protections include thermal
shutdown with hysteresis, delayed overload
protection, and open loop failure protection.

Features
■ Universal input mains range:
– input voltage 90 - 264 VAC
– frequency 45 - 65 Hz
■ Single-output voltage: 12 V at 1 A continuous
operation
■ Standby mains consumption: < 30 mW at
230 VAC
■ Average efficiency: > 80%
■ Fully protected against faults (overload,
feedback disconnection and overheating)
■ EMI: according to EN55022-Class-B
■ RoHS compliant