STCF02_07 Datasheet, PDF (1/19 Pages) STMicroelectronics – High power white led driver

STCF02
High power white led driver
General features
■ Buck-boost DC/DC Converter
■ Drives one power white led:
up to 600mA between 2.7 to 4.5V
■ Led temperature protection
■ Output current control
■ 1.8 MHz (typ) fixed frequency PWM
■ Synchronous rectification
■ High efficiency across the total input voltage
range
■ Operational modes:
- Shutdown mode
- Shutdown mode with NTC
- Flash mode up to 600 mA
- Medium flash mode
- Torch mode: up to 250 mA
■ Adjustable current in all three modes
■ LED disconnected from the battery in
shutdown mode
■ Programmable safety shutdown in flash mode
■ LED short and open circuit protection
■ Overvoltage protection
■ < 1µA Shutdown current
■ QFN20 4mm x 4 mm package
Applications
■ Cell phone and smart phones
■ Camera flashes/strobes
■ PDAS and digital still cameras
QFN20 (4mm x 4mm)
Description
The STCF02 is a high efficiency power supply
solution to drive a single flash LED in camera
phone, PDAs and other hand-held devices. It is a
buck-boost converter that guarantees a proper
LED current control over the battery voltage
(particularly in the case, when the output voltage
is lower than the input voltage); the output current
control ensures a good current regulation over the
forward voltage spread characteristics of the
Flash LED.
Three logic input signals can select 5 modes of
operation: Shutdown mode (quiescent current
less than 1µA typ), Shutdown mode with NTC
active, Torch mode (drives the LED up to 250mA),
Flash mode (up to 600mA), and Medium flash
mode (reduces the flash current).
This highly efficient converter is able to accept
input current from the battery (lower than 1.5A),
while limiting the peak inductor current to 2.3A
(typ). Other features include Soft start control,
thermal shutdown, short circuit protection,
overvoltage protection, and LED temperature
protection. An alternative to LED temperature
protection is that a safety flash time-out feature
can be implemented instead. This device is
available in a QFN20, 4mm x 4mm, no-lead
package (height is less than 1mm).
Order code
Part number
STCF02PNR
Package
QFN20 (4x4 mm)
Packaging
4500 parts per reel
February 2007
Rev. 6
1/19
www.st.com
19