LTC3210



3210fb

Features

Description

applications

typical application

MAIN/CAM LED Controller

in 3mm

× 3mm QFN

designed to drive four MAIN LEDs and one high current

CAM LED for camera lighting. The LTC3210 requires only

four small ceramic capacitors and two current set resis-

tors to form a complete LED power supply and current

controller.

Built-in soft-start circuitry prevents excessive inrush cur-

rent during start-up and mode changes. High switching

frequency enables the use of small external capacitors.

Independent MAIN and CAM full-scale current settings

are programmed by two external resistors. Shutdown

mode and current output levels are selected via two logic

inputs.

The full-scale current through the LEDs is programmed

via external resistors. ENM and ENC are toggled to adjust

the LED currents via internal counters and DACs. The

part is shut down when both ENM and ENC are low for

150µs (typ).

The charge pump optimizes efficiency based on the volt-

age across the LED current sources. The part powers up

in 1x mode and will automatically switch to boost mode

whenever any enabled LED current source begins to en-

ter dropout. The LTC3210 is available in a 3mm

× 3mm

16-lead QFN package.

C1P

C1M

C2P

RM

RC

GND

C2M

CPO

MLED1

MLED2

MLED3

MLED4

CLED

ENM

ENC

LTC3210

C1

2.2µF

C2

2.2µF

C3

2.2µF

30.1k

1%

24.3k

1%

ENM

ENC

C4

2.2µF

3210 TA01

MAIN

CAM

n

Low Noise Charge Pump Provides High Efficiency

with Automatic Mode Switching

n

Multimode Operation: 1x, 1.5x, 2x

n

Individual Full-Scale Current Set Resistors

n

Up to 500mA Total Output Current

n

Single Wire EN/Brightness Control for MAIN and

CAM LEDs (8 Brightness Steps)

n

64:1 Brightness Control Range for MAIN Display

n

Four 25mA Low Dropout MAIN LED Outputs

n

One 400mA Low Dropout CAM LED Output

n

Low Noise Constant Frequency Operation*

n

Low Shutdown Current: 3µA

n

Internal Soft-Start Limits Inrush Current During

Startup and Mode Switching

n

Open/Short LED Protection

n

No Inductors

n

3mm

× 3mm 16-Lead Plastic QFN Package

3.0

60

80

100

3210 TA01b

40

20

50

70

90

30

10

0

3.6

3.8

3.2

4.0

3.4

4.4

4.2

4 LEDs AT 9mA/LED

4-LED MAIN Display

n

Multi-LED Light Supply for Cellphones/DSCs/PDAs

L

, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear

Technology Corporation. All other trademarks are the property of their respective owners.

*Protected by U.S. Patents including 6411531.