July 2009

Doc ID 5656 Rev 10

1/27

AN993

Application note

Electronic ballast with PFC using L6574 and L6561

Introduction

Dedicated ICs for lamp ballast applications are now replacing the old solutions based on

bipolar transistors driven by a saturable pulse transformer.

The L6574 is a high-performance ballast driver, designed using 600-V BCD offline

technology, which ensures all the features needed to properly drive and control a fluorescent

bulb. It is provided with built-in VCO start-up sequence circuitry, protections, and an

operation amplifier for implementing a closed-loop control of the lamp current.

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