PAM2804 Datasheet, PDF (1/11 Pages) Power Analog Micoelectronics – 1A Step-Down Constant Current, High Efficiency LED Driver

PAM2804
1A Step-Down Constant Current, High Efficiency LED Driver
Features
n Efficiency up to 93%
n 180 μA(TYP.) Quiescent Current
n Output Current: Up to 1A
n Internal Synchronous Rectifier
n 1.5MHz Switching Frequency
n Soft Start
n Under-Voltage Lockout
n Short LED Protection
n Open LED Protection
n Thermal Shutdown
n 5-pin Small SOT23-5 Packages
n Pb-Free Package
Applications
n 3AA or 4AA Batteries Powered Flashlight
n 1 Cell Li-Ion Battery Powered Flashlight
General Description
The PAM2804 is a step-down constant current
LED driver. When the input voltage down to lower
than LED forward voltage, then PAM2804 run into
LDO mode.
The PAM2804 supports a range of input voltages
from 2.5V to 6.0V, allowing the use of a single
Li+/Li-polymer cell, 3AA or 4AA cell, USB, and
other standard power sources.
The FB voltage is only 0.1V to achieve high
efficiency.
PAM2804 employ internal power switch and
synchronous rectifier to minimize external part
count and realize high efficiency.
During shutdown, the input is disconnected from
the output and the shutdown current is less than
1μA. Other key features include under-voltage
lockout to prevent deep battery discharge of the
Li+ battery.
.
Typical Application
1 Cell Li-Ion Battery
3AA or 4AA Batteries
V
IN
C
IN
10µF
VIN SW
GND
FB
EN
L
4.7µH
1~5W
WLED ^Co
10µF
Rs
ILED =0.1/Rs
Power Analog Microelectronics, Inc
www.poweranalog.com
1
10/2010 Rev1.0