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L6574

September 2003

s

HIGH VOLTAGE RAIL UP TO 600V

s

dV/dt IMMUNITY ± 50 V/ns IN FULL

TEMPERATURE RANGE

s

DRIVER CURRENT CAPABILITY:

250mA SOURCE

450mA SINK

s

SWITCHING TIMES 80/40ns RISE/FALL

s

WITH 1nF LOAD

s

CMOS SHUT DOWN INPUT

s

UNDER VOLTAGE LOCK OUT

s

PREHEAT AND FREQUENCY SHIFTING

TIMING

s

SENSE OP AMP FOR CLOSED LOOP

CONTROL OR PROTECTION FEATURES

s

HIGH ACCURACY CURRENT CONTROLLED

OSCILLATOR

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INTEGRATED BOOTSTRAP DIODE

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CLAMPING ON VS.

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SO16, DIP 16 PACKAGES

DESCRIPTION

In order to ensure voltage ratings in excess of

600V, the L6574 is manufactured with BCD OFF

LINE technology, which makes it well suited for

lamp ballast applications.

The device is intended to drive two power MOS-

FETS, in the classical half bridge topology, ensur-

ing all the features needed to drive and properly

control a fluorescent bulb.

A dedicated timing section in the L6574 allows the

user set the necessary parameters for proper pre-

heat and ignition of the lamp.

Also, an OP AMP is available to implement closed

loop control of the lamp current during normal

lamp burning.

An integrated bootstrap section, eliminating the nor-

mally required bootstrap diode and the zener clamp-

ing on Vs, makes the L6574 well suited for low cost

applications where few additional components are

needed to build a high performance ballast.

SO16N

DIP16

ORDERING NUMBERS:

L6574D

L6574

CFL/TL BALLAST DRIVER PREHEAT AND DIMMING

BLOCK DIAGRAM

GND

Imin

VCO

EN1

EN2

OUT

LOAD

H.V.

LVG

UV

DETECTION

HVG

BOOTSTRAP

DRIVER

HVG

DRIVER

LVG DRIVER

Vthpre

Ifs

Imax

Cf

OP AMP

+

-

OPOUT

OPIN-

OPIN+

DEAD

TIME

DRIVING

LOGIC

CONTROL

LOGIC

+

-

Ipre

+

-

+

-

+

-

LEVEL

SHIFTER

D97IN493A