August 2006

Rev 3

1/16

AN1895

Application note

EVAL6562-375W Evaluation Board

L6562-based 375W FOT-controlled PFC Pre-regulator

Introduction

This application note describes a 375W evaluation board based on the L6562 Transition-

mode Power Factor Correction (PFC) controller (order code: EVAL6562-375W).

The board implements a 375W, wide-range mains input, PFC pre-regulator that is suitable

for a 300/350W ATX12V power supply unit (PSU).

To enable the use of a low-cost device like the L6562 at a power level that is usually

prohibitive for this device, the chip operates with a Fixed-Off-Time (FOT) control system.

This allows Continuous Conduction Mode operation, normally achievable with more

expensive control chips and more complex control architectures.

EVAL6562-375W evaluation board

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