AAT1149A Datasheet, PDF (1/17 Pages) Advanced Analogic Technologies – 2.2MHz Fast Transient 400mA Step-Down Converter

SwitchReg^TM
PRODUCT DATASHEET
AAT1149A
2.2MHz Fast Transient 400mA Step-Down Converter
General Description
The AAT1149A SwitchReg is a 2.2MHz step-down con-
verter with an input voltage range of 2.2V to 5.5V. It is
optimized to react quickly to load variations and operate
with a tiny 0603 inductor that is only 1mm tall.
The AAT1149A can deliver 400mA of load current and
operates in PWM only mode for low noise operation. The
2.2MHz switching frequency minimizes the size of exter-
nal components while keeping switching losses low.
The AAT1149A is optimized for low noise portable
applications.
The AAT1149A is available in a Pb-free, space-saving
5-pin wafer-level chip scale (WLCSP) package and is
rated over the -40°C to +85°C temperature range.
Features
• Ultra-Small 0603 Inductor (Height = 1mm)
• V_IN Range: 2.2V to 5.5V
• V_OUT Fixed 1.875V
• 400mA Max Output Current
• Up to 98% Efficiency
• 3mA No Load Quiescent Current
• 2.2MHz Switching Frequency
• 70μs Soft Start
• Fast Load Transient
• Over-Temperature Protection
• Current Limit Protection
• 100% Duty Cycle Low-Dropout Operation
• <1μA Shutdown Current
• 0.9x1.2mm WLCSP 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 = 3.6V
C2
4.7µF
U1
AAT1149A
IN
LX
EN
FB
AGND PGND
PGND PGND
V_OUT = 1.875V
L1 2.2µH
C1
4.7µF
1149A.2008.08.1.1
www.analogictech.com
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