LM2753 Datasheet, PDF (1/8 Pages) National Semiconductor (TI) – High Power Switched Capacitor Voltage Convertor/Flash LED Driver

February 2005
LM2753
High Power Switched Capacitor Voltage Convertor/Flash
LED Driver
General Description
The LM2753 is capable of driving a Flash LED with a pulsed
current of 400mA at an input voltage of 3.6V. A switched
capacitor doubler, the LM2753 provides a regulated 5V out-
put (V_OUT) over an input supply range of 3.0V to 5.5V. The
switched output, I_OUT, takes less than 10ns to turn on and
provide maximum current to a Flash LED. Flash LED current
is set via a ballast resistor. Continuous illumination current
(Torch Mode) is programmed by connecting a resistor be-
tween I_OUT and V_OUT. This device uses only three small,
low-cost ceramic capacitors.
LM2753 uses Pulse Frequency Modulation (PFM) regula-
tion. Typical operating frequency is 725kHz. Under no-load
conditions, LM2753 operates on only 60µA. If the output is
connected to ground, the charge pump stays in the gain of 1
which helps limit the input current to 300mA (typ.)
LM2753 is available in a 10-pin No Pullback Leadless Lead-
frame Package: LLP-10.
Features
n Input Voltage Range: 3.0V to 5.5V
n Regulated 5V Output
n 250mA Output Current with a 3.6V input
n 400mA Pulsed Output Current (up to 500ms duration)
n 60µA (typ.) Quiescent Current
n PFM Regulation
n Inductor-less solution: requires only 3 small capacitors
n <1µA Typical Shutdown Current
n 10-pin LLP Package (No Pullback):
3mm x 3mm x 0.75mm
Applications
n Cell Phone Camera Flash
n General Purpose Regulated Voltage Output, High
Current Supply
Typical Application Circuit
20140601
© 2005 National Semiconductor Corporation DS201406
www.national.com