December 2012

Doc ID 022455 Rev 2

1/33

AN4007

Application note

EVLVIP37LE5V3A: 15 W (5 V - 3 A) wide range single-output

demonstration board

By Fabio Cacciotto

Introduction

In several applications, such as LCD or plasma TVs, desktop computers, etc., the power

supply that converts the energy from the main, often includes two modules: the main power

supply that provides most of the power and is OFF when the application is OFF or in

standby mode, and the auxiliary power supply that provides energy only to some specific

parts of the equipment such as USB ports, remote receivers, or modems but is still ON

when the application is in standby mode.

It is often required that, in standby condition, the equipment input power is as low as

possible which means the input power of the auxiliary power supply in no load or light load

condition is reduced as low as possible.

This application note introduces a new offline high voltage converter from the VIPerPlus

family, the VIPER37LE and the presented demonstration board meets the specifications of a

wide range of auxiliary power supplies for said applications. Furthermore, it is optimized for

very low standby consumption, therefore helping to meet the most stringent energy saving

requirements.

Figure 1.

Demonstration board image: power supply board

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