PAM2312 Datasheet, PDF (1/14 Pages) Power Analog Micoelectronics – 1A Step-Down DC-DC Converter

Features
n Efficiency up to 96%
n Only 40 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 Circuit Protection
n Thermal Shutdown
n 5-pin Small SOT23-5 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
PAM2312
1A Step-Down DC-DC Converter
General Description
The PAM2312 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
PAM2312 provides a power-saving Pulse-
Skipping Modulation (PSM) mode to reduce
quiescent current under light load operation to
save power.
The PAM2312 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, while the part number suffix PAM2312-
XX indicates pre-set output voltage of 3.3V, 2.8V,
2.5V, 1.8V, 1.5V, 1.2V or adjustable. 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 1 μA. Other key features
include under-voltage lockout to prevent deep
battery discharge.
The PAM2312 is available in SOT23-5 packages.
Fixed Output Voltage
VIN
CIN
10µF
L
VIN SW
GND
VOUT
EN /FB
Vo
Co
10µF
Adjustable Output Voltage
VIN
C IN
10µF
VIN SW
GND
VOUT/FB
EN
L
R1
R2
Vo
C
FW
Co
10µF
Power Analog Microelectronics, Inc
www.poweranalog.com
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R2
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05/2010 Rev1.0