AAT1147 Datasheet, PDF (1/18 Pages) Advanced Analogic Technologies – High Efficiency, Low Noise, Fast Transient 400mA Step-Down Converter

DATA SHEET
AAT1147
High Efficiency, Low Noise, Fast Transient 400mA Step-Down Converter
General Description
The AAT1147 SwitchReg is a member of Skyworks' Total
Power Management IC™ (TPMIC™) product family. It is
a fixed frequency 1.4MHz step-down converter with an
input voltage range of 2.7V to 5.5V and output voltage
as low as 0.6V.
The AAT1147 is optimized for low noise portable applica-
tions, reacts quickly to load variations, and reaches peak
efficiency at heavy load.
The AAT1147 output voltage is programmable with
external feedback resistors. It can deliver 400mA of load
current while maintaining high power efficiency. The
1.4MHz switching frequency minimizes the size of exter-
nal components while keeping switching losses low.
The AAT1147 is available in a Pb-free, space-saving
2.0x2.1mm SC70JW-8 package and is rated over the
-40°C to +85°C temperature range.
Features
• V_IN Range: 2.7V to 5.5V
• V_OUT Adjustable from 0.6V to V_IN
• 400mA Output Current
• Up to 98% Efficiency
• Low Noise, 1.4MHz Fixed Frequency PWM Operation
• Fast Load Transient
• 150μs Soft Start
• Over-Temperature and Current Limit Protection
• 100% Duty Cycle Low Dropout Operation
• <1μA Shutdown Current
• 8-Pin SC70JW Package
• Temperature Range: -40°C to +85°C
Applications
• Cellular Phones
• Digital Cameras
• Handheld Instruments
• Microprocessor/DSP Core /IO Power
• PDAs and Handheld Computers
• USB Devices
Typical Application
V_IN
C2
4.7µF
U1
AAT1147
3 _VIN
LX ⁴
1 _EN
OUT ²
5 _{AGND PGND} 7
8 _{PGND PGND} 6
V_O = 1.8V
L1
4.7µH _R1
118k
R2
59k
C1
4.7µF
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [e-mail] • www.skyworksinc.com
201986A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • May 23, 2012
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