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POWER MANAGEMENT

SC605

Charge Pump

Flash LED Driver

December , 2005

Description

Features

Typical Application Circuit

Features

Typical Application Circuit

Applications

The SC605 is a high-current charge pump designed spe-

cifically for use with white LEDs used in camera flash ap-

plications. Only two small bucket capacitors are required

to develop the output drive, providing a low EMI solution

compared to inductive boost regulators.

The SC605 has two modes of operation: Flash mode and

Spotlight mode. In Flash mode, the SC605 is capable of

delivering 500mA of regulated current for a duration of

500ms or up to 700mA for a reduced duration. In Spotlight

mode the SC605 can output 20%, 30%, or 40% of the Flash

mode current and remain enabled continuously.

An external resistor is connected in series with the LED to

set the current. In Flash mode, this resistor can dissipate

up to 0.75mW, reducing the power dissipation require-

ment of the SC605. The Flash input (FLASH) overrides

the control inputs (CTRL0 and CTRL1) to ensure the Flash

function has the highest priority.

The thermally efficient MLPD-12 package and ceramic

bypass and bucket capacitors help make the SC605 a

high output current driver that requires a minimal amount

of PCB area.



Two selectable modes - Flash and Spotlight



Up to 700mA output - Flash mode



Up to 280mA output - Spotlight mode



500mA output over specified temperature and volt-

age ranges - Flash mode



Spotlight mode selectable to 20%, 30%

and 40% of Flash current



3.0V to 5.25V input range



Flash control pin for synchronization to

a camera module or graphics controller



Short circuit, over-voltage and

over-temperature protection



Soft-start functionality



Three control inputs for maximum versatility



Shutdown current < 2μA



Micro-lead package MLPD-12, 3mm x 3mm

VBAT

0µF

µF

white LED

CTRL

CTRL0

FLASH

0.5W

SC605

VIN

1

FLASH

6

CTRL0

8

CTRL1

9

NC

5

VOUT

11

ISET

7

C1+

10

C1-

4

C2+

12

C2-

2

µF

µF

GND

3



Mobile Camera Phones



Digital Cameras



PDAs with Built-in Cameras