AAT2500M
400mA Step-Down Converter and 300mA LDO
General Description
The AAT2500M is a high efficiency 400mA step-
down converter and 300mA low dropout (LDO) lin-
ear regulator for applications where power efficien-
cy and solution size are critical. The typical input
power source can be a single-cell Lithium-ion/poly-
mer battery or a 5V or 3.3V power bus.
The step-down converter is capable of delivering up
to 400mA output current, uses a typical switching
frequency of 1.8MHz to greatly reduce the size of
external components, offers high speed turn-on and
maintains a low 25µA no load quiescent current.
The LDO is capable of delivering up to 300mA out-
put current.
The AAT2500M is available in the Pb-free, space-
saving 12-pin TSOPJW package and is rated over
the -40°C to +85°C operating temperature range.
Features
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SystemPower
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V
IN
Range: 2.7V to 5.5V
Output Current:
— Step-Down Converter: 400mA
— LDO: 300mA
Low Quiescent Current
— 130µA Combined for Both Step-Down
Converter plus LDO
90% Efficient Step-down Converter (at 100mA)
Integrated Power Switches
100% Duty Cycle
1.8MHz Switching Frequency
Current Limit Protection
Automatic Soft-Start
Over Temperature Protection
TSOPJW-12 Package
-40°C to +85°C Temperature Range
Applications
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Cellular Phones
Digital Cameras
Handheld Instruments
Micro Hard Disc Drives
Microprocessor / DSP Core / IO Power
Optical Storage Devices
PDAs and Handheld Computers
Portable Media Players
Typical Application
AAT2500M
Input Supply
2.7V to 5.5V
4.7µF
IN_BUCK
LX
FB_BUCK
V
OUT_BUCK
2.2µH
R1
R2
IN_LDO
1µF
OUT_LDO
V
OUT(LDO)
C2
4.7µF
Enable Buck
Enable LDO
EN_BUCK
EN_LDO
AGND PGND
C1
2.2µF
2500M.2007.06.1.0
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ANALOGICTECH [ ADVANCED ANALOGIC TECHNOLOGIES ]
