AN4007 Datasheet, PDF (1/33 Pages) STMicroelectronics – In several applications, such as LCD or plasma TVs

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
December 2012
Doc ID 022455 Rev 2
1/33
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