IS31LT3929

Preliminary

Integrated Silicon Solution, Inc. – www.issi.com

Rev. A, 4/2/2012

1

Flyback configuration LED driver with integrated PFC and no feedback

General Description

The IS31LT3929 is a primary side, peak current

mode, isolated type HBLED driver.

The device

works at a constant frequency in discontinuous

conduction mode to provide a constant power to the

input.

It eliminates the need for an opto-coupler,

TL431, or any other type of secondary side feedback.

It operates from an input voltage range of 85VAC to

265VAC.

The IS31LT3929 integrates over current/voltage

protection, as well as includes a thermal shutdown to

halt the switching action in the case of abnormally

high operating temperatures.

Features

•

Power factor correction to > 0.9

•

3% typical current accuracy

•

No loop compensation required

•

Wide input voltage range: 85V to 265VAC

•

Internal over-temperature protection

Applications

•

AC/DC constant current LED driver

•

General AC/DC power supply

•

General LED Lighting

Typical Operating Circuit

85~265Vac

Fuse

BD

C1

C2

C3

C4

C5

C6

R1

R2

R3

R4

R5

Rcs

R6

R7

R8

D1

D3

D2

D4

LED1

LEDn

TR

Q1

U1

3929

GATE

CS

GND

NC

VCC

VSINE

FSET

FB

Figure 1 Typical Operating Circuit

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to obtain the latest version of this device specification before relying on any published information and before placing orders for products.

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authorized for use in such applications unless Integrated Silicon Solution, Inc. receives written assurance to its satisfaction, that:

a.) the risk of injury or damage has been minimized;

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