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POWER MANAGEMENT

SC615

Charge Pump

Flash LED Driver

July 11, 2005

Application Circuit

Applications

Features

500mA Output Current - Flash Mode

3.0V to 5.25V Input Range

Two Selectable Modes - Flash and Spotlight

External Flash Control Pin for Synchronization to a

Camera Module or Graphics Controller

Spotlight Mode Current Setting - 100mA

Short Circuit, Over-Voltage, and Over-Temperature

Protection

Soft-Start Functionality

Two Control Inputs for Maximum Versatility

Shutdown Current < 2

µA

Micro Lead-frame Package MLPD-10, 3mm x 3mm

Mobile Camera Phones

Digital Cameras

PDAs with Built-in Cameras

Multi-LED Backlit LCDs

The SC615 is a high-current charge pump designed spe-

cifically for use with white LEDs used in camera flash

applications. Only two small bucket capacitors are re-

quired to develop the output drive, providing a low EMI

solution compared to inductive boost regulators.

The SC615 has two modes of operation: Flash mode

and Spotlight mode. The SC615 is capable of delivering

500mA of peak current for a duration of 500ms in Flash

mode. In Spotlight mode the SC615 outputs 100mA

and can remain enabled continuously.

A minimum 0.5

Ω sense resistor is used to set the cur-

rent through the LED in both modes. This resistor dissi-

pates up to 0.125W, reducing the power dissipation re-

quirement of the SC615. The flash input (FLASH) over-

rides the control input (CTRL) to make sure the flash func-

tion is activated when called for.

The thermally efficient MLPD-10 package and ceramic

bypass and bucket capacitors help make the SC615 a

high output current driver that requires a minimal amount

of PCB area.

Description

3.0V to 5.25V

SC615

VIN

1

C2-

2

C2+

10

C1-

4

C1+

8

VOUT

9

FLASH

5

CTRL

7

GND

3

ISET

6

1

µF

1

µF

FLASH

CTRL

1

µF

white LED

0.5

Ω

10

µF