AAT1155
1MHz 2.5A Step-Down DC/DC Converter
General Description
The AAT1155 SwitchReg™ is a member of
AnalogicTech's Total Power Management IC™
(TPMIC™) product family. The step-down switch-
ing converter is ideal for applications where high
efficiency, small size, and low ripple are critical.
Able to deliver 2.5A with an internal power MOS-
FET, the current-mode controlled IC provides high
efficiency. Fully internally compensated, the
AAT1155 simplifies system design and lowers
external parts count.
The AAT1155 is available in a Pb-free MSOP-8
package and is rated over the -40°C to +85°C tem-
perature range.
Features
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SwitchReg
™
5.5V Max Supply Input
Fixed or Adjustable V
OUT
: 1.0V to 4.2V
2.5A Output Current
Up to 95% Efficiency
Integrated Low On Resistance Power
Switches
Internally Compensated Current Mode Control
1MHz Switching Frequency
Constant PWM Mode
Low Output Ripple With Light Load
Internal Soft Start
Current Limit Protection
Over-Temperature Protection
MSOP-8 Package
-40°C to +85°C Temperature Range
Applications
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Cable/DSL Modems
Computer Peripherals
High Efficiency Conversion from 5V or 3.3V
Supply
Network Cards
Set-Top Boxes
Typical Application
INPUT
10µF
VP
FB
AAT1155
ENABLE
100Ω
VCC
LX
LX
1.5µH
OUTPUT
GND
0.1µF
120µF
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