AN3286 Datasheet, PDF (1/42 Pages) STMicroelectronics – This document describes

AN3286
Application note
EVLVIPER25L-10WSB: 5 V/10 W, quasi-resonant isolated flyback
Introduction
This document describes a 5 V - 2 A SMPS using VIPer25, a current-mode offline converter,
specifically designed to build quasi-resonant flyback converters. Quasi-resonant operation,
in conjunction with other features of the device (very low quiescent currents; valley skipping
operation at light load; burst mode operation at very low or disconnected load) helps to
reach very good requirements both in terms of efficiency and in terms of consumption from
the mains at light load, allowing to meet the most modern SMPS standards.
The other features of the device are: 800 V avalanche rugged power section, limiting current
with adjustable set point, onboard soft-start, safe auto-restart after a fault condition, and
feed-forward correction.
The available protections are: adjustable and accurate overvoltage protection, thermal
shutdown with hysteresis, and delayed overload protection.
Figure 1. Demonstration board image
August 2011
Doc ID 17998 Rev 1
1/42
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