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POWER MANAGEMENT

SC615A

Charge Pump

Flash LED Driver

September 22, 2005

Typical Application Circuit

Applications

Features

Two Selectable Modes - Flash and Spotlight

Up to 700mA Output - Flash Mode

Up to 280mA Output - Spotlight Mode

500mA Over Temperature Range and Voltage

Range - Flash Mode

Spotlight mode set to 40% of Flash Current

3.0V to 5.25V Input Range

External Flash Control Pin for Synchronization to a

Camera Module or Graphics Controller

Short Circuit, Over-Voltage, and Over-Temperature

Protection

Soft-Start Functionality

Two Control Inputs for Maximum Versatility

Shutdown Current < 2

µA

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

Mobile Camera Phones

Digital Cameras

PDAs with Built-in Cameras

The SC615A 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 SC615A has two modes of operation: Flash mode

and Spotlight mode. In Flash mode, the SC615A is ca-

pable of delivering 500mA of regulated current for a du-

ration of 500ms or up to 700mA for a reduced duration.

In Spotlight mode the SC615A outputs 40% of the Flash

mode current and can 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 175mW, reducing the power dissipation

requirement of the SC615A. The flash input (FLASH)

overrides the control input (CTRL) to make sure the flash

function is activated when called for.

The thermally efficient MLPD-10 package and ceramic

bypass and bucket capacitors make the SC615A a high

output current driver that requires minimal PCB area.

Description

3.0V to 5.25V

SC615A

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

C1

C2