ZLED7x20 Datasheet

© 2016 Integrated Device Technology, Inc.

3

April 20, 2016

Contents

1

IC Characteristics .......................................................................................................................................................... 5

1.1

Absolute Maximum Ratings ................................................................................................................................... 5

1.2

Operating Conditions ............................................................................................................................................. 5

1.3

Electrical Parameters............................................................................................................................................. 6

1.4

Typical Operation Graphs ...................................................................................................................................... 7

2

Circuit Description ....................................................................................................................................................... 12

2.1

ZLED7x20 Overview ............................................................................................................................................ 12

2.2

Control of Output Current via External Sense Resistor Rs .................................................................................. 12

2.3

Control of Output Current via an External DC Control Voltage on the ADJ Pin ................................................... 12

2.4

Additional Requirements if the VIN Input Voltage has a High Slew Rate .............................................................. 13

2.5

Control of Output Current via a PWM Signal on the ADJ Pin............................................................................... 13

2.6

Control of Output Current via a Microcontroller Signal on the ADJ Pin ................................................................ 13

2.7

Shutdown Mode ................................................................................................................................................... 13

2.8

ZLED7x20 Protection Features............................................................................................................................ 14

2.8.1

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

2.8.2

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

3

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

3.1

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

3.2

Thermal Considerations for Application Design ................................................................................................... 17

3.2.1

Temperature Effects of Load, Layout, and Component Selection ................................................................ 17

3.2.2

Temperature Effects of Low Supply Voltage VIN........................................................................................... 17

3.3

External Component Selection ............................................................................................................................ 17

3.3.1

Sense Resistor Rs ........................................................................................................................................ 17

3.3.2

Inductor L1.................................................................................................................................................... 18

3.3.3

Bypass Capacitor C1 .................................................................................................................................... 19

3.3.4

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

3.3.5

Capacitor C3 for Reducing Output Ripple..................................................................................................... 21

3.3.6

Diode D1....................................................................................................................................................... 21

3.4

Application Circuit Layout Requirements ............................................................................................................. 21

4

ESD Protection............................................................................................................................................................ 22

5

Pin Configuration and Package ................................................................................................................................... 22

5.1

SOT89-5 Package Pin-out and Dimensions for the ZLED7020 ........................................................................... 22

5.2

DFN-5 Package Pin-out and Dimensions for the ZLED7320, ZLED7520 and ZLED7720 ................................... 24

6

Ordering Information ................................................................................................................................................... 26

7

Related Documents..................................................................................................................................................... 26

8

Glossary ...................................................................................................................................................................... 26

9

Document Revision History ......................................................................................................................................... 27