PAM2309 Datasheet, PDF (1/16 Pages) Power Analog Micoelectronics – 1A Step-Down DC-DC Converter

Features
n Efficiency up to 96%
n Only 40μA(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 Circuit Protection
n Thermal Shutdown
n 5-pin Small SOT23-5, DFN2x2 6-Pin and
QFN3x3 16-Pin Packages
n Pb-Free Package
Applications
n Cellular Phone
n Portable Electronics
n Wireless Devices
n Cordless Phone
n Computer Peripherals
n Battery Powered Widgets
n Electronic Scales
n Digital Frame
Typical Application
PAM2309
1A Step-Down DC-DC Converter
General Description
The PAM2309 is a step-down current-mode, DC-
DC converter. At heavy load, the constant-
frequency PWM control performs excellent
stability and transient response. To ensure the
longest battery life in portable applications, the
PAM2309 provides a power-saving Pulse-
Skipping Modulation (PSM) mode to reduce
quiescent current under light load operation to
save power.
The PAM2309 supports a range of input voltages
from 2.5V to 5.5V, allowing the use of a single
Li+/Li-polymer cell, multiple Alkaline/NiMH cell,
USB, and other standard power sources. The
output voltage is adjustable from 0.6V to the input
voltage. All versions employ internal power switch
and synchronous rectifierfor 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
0.1μA. Other key features include under-voltage
lockout to prevent deep battery discharge.
The PAM2309 is available in SOT23-5, DFN2x2 6-
Pin and QFN3x3 16-Pin packages.
V_IN
C_IN
10μF
VIN SW
GND
VOUT/FB
EN
L
R1
R2
Vo
C_FW
Co
10μF
VO
=
0.5 ´
æçè_{1 +}
R1
R2
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Power Analog Microelectronics,Inc
www.poweranalog.com
1
08/2009 Rev 1.1