October 2006

Rev. 4

1/16

16

STCF01

Step-up converter for cell phone camera flash LEDs

General features

external resistors

current

Description

The STCF01 is a dedicated IC designed to drive

two, three, or four white, cell phone camera flash

LEDs with constant current. The step-up (boost)

converter input is connected directly to the battery,

and its converter output voltage is automatically

determined using current feedback-based duty

cycle control.

The STCF01 has a dedicated pin for two levels of

LED current selection. An external resistor is used

to set the required current for each level.

Compared to the linear current control technique,

this method allows designers to achieve the best

and most efficient performance possible with the

selected current, thereby avoiding linear element

losses.

The Shutdown (SHDN) pin saves power when the

camera flash is not used by consuming less than

0.1µA of current. When the SHDN pin is high

(logic '1'), the device is turned OFF and there is no

DC current path from the supply to the white LEDs

(Load Disconnect). If it is held to GND, the output

current continuously flows through the LEDs

(Torch mode). The SHDN pin, when it is set to low

(logic '0'), is also used to set the flash function

time duration.

www.st.com

DFN10L (3x3)

Order code

Part number

Package

Packaging

STCF01PMR

DFN10L (3mm x 3mm)

4500 parts per reel