ZLED7330

High Current 40V LED Driver with Switch Dimming

Data Sheet

August 16, 2011

© 2011 Zentrum Mikroelektronik Dresden AG — Rev.1.2

All rights reserved. The material contained herein may not be reproduced, adapted, merged, translated, stored, or used without

the prior written consent of the copyright owner. The information furnished in this publication is subject to changes without notice.

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Contents

1

IC Characteristics .......................................................................................................................................................... 6

1.1

Absolute Maximum Ratings ................................................................................................................................... 6

1.2

Operating Conditions ............................................................................................................................................. 6

1.3

Electrical Parameters............................................................................................................................................. 7

1.4

Typical Operation Graphs ...................................................................................................................................... 8

2

Circuit Description ....................................................................................................................................................... 13

2.1

ZLED7x30 Overview ............................................................................................................................................ 13

2.2

Control of Output Current via External Sense Resistor Rs .................................................................................. 13

2.3

Multi-Mode Switch Dimming................................................................................................................................. 13

2.4

ZLED7x30 Protection Features............................................................................................................................ 14

2.4.1

Thermal Shut-down Protection ..................................................................................................................... 14

2.4.2

LED Open-Load Protection........................................................................................................................... 14

3

Application Circuit Design............................................................................................................................................ 15

3.1

Applications.......................................................................................................................................................... 15

3.2

Thermal Considerations for Application Design ................................................................................................... 16

3.2.1

Temperature Effects of Load, Layout, and Component Selection................................................................. 16

3.2.2

3.3

External Component Selection............................................................................................................................. 16

3.3.1

Sense Resistor Rs ........................................................................................................................................ 16

3.3.2

Inductor L1.................................................................................................................................................... 17

3.3.3

Bypass Capacitor C1 .................................................................................................................................... 18

3.3.4

De-bouncing Capacitor C2............................................................................................................................ 20

3.3.5

Capacitor C3 for Reducing Output Ripple..................................................................................................... 20

3.3.6

Diode D1....................................................................................................................................................... 20

3.4

Application Circuit Layout Requirements ............................................................................................................. 20

4

ESD Protection............................................................................................................................................................ 21

5

Pin Configuration and Package ................................................................................................................................... 21

6

Ordering Information ................................................................................................................................................... 22

7

Document Revision History ......................................................................................................................................... 23