March 2007

Rev 1

1/29

AN2485

Application note

400 W FOT-controlled PFC pre-regulator with the L6563

Introduction

This application note describes an evaluation board based on the Transition-mode PFC

controller L6563 and presents the results of the bench evaluation. The board implements a

400 W, wide-range mains input, a PFC pre-conditioner suitable for ATX PSU, or a flat

screen display. The chip is operated with Fixed-Off-Time control in order to use a low-cost

device like the L6563 which is usually prohibitive at this power level. Fixed-Off-Time control

allows Continuous Conduction Mode operation which is normally achieved with more

expensive control chips and more complex control architectures.

L6563 400W FOT PFC Demo board (EVAL6563-400W)

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