STCF01 Datasheet, PDF (1/16 Pages) STMicroelectronics – Step-up Converter for Cell Phone Camera Flash LEDs

STCF01
Features
Step-up Converter for Cell Phone Camera Flash LEDs
Preliminary Data
I Supply voltage range: 2.6V to 5.5V
I 17V Maximum Output Voltage
I Two levels of current up to 300mA set with
external resistors
I Dedicated pin to select the required level of
current
I Operating frequency: 1.5MHz: PWM Controller
I Torch mode supported
I Shutdown pin with true load disconnection
I Efficiency: 90% at 100mA; 80% at 300mA
I DFN10L (3mm x 3mm) Package
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
DFN10L (3x3)
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.
Order Codes
Type
STCF01PMR
Package
DFN10L (3mm x 3mm)
Comments
4500 parts per reel
October 2005
This is preliminary information on a new product now in development or undergoing evaluation. Details are subject to
change without notice.
Rev. 1
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