AAT1149B Datasheet, PDF (1/17 Pages) Advanced Analogic Technologies – 2.2MHz Fast Transient 400mA Step-Down Converter

DATA SHEET
AAT1149B
2.2MHz Fast Transient 400mA Step-Down Converter
General Description
The AAT1149B 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 AAT1149B can deliver 400mA of load current while
maintaining a low 45μA no load quiescent current. The
2.2MHz switching frequency minimizes the size of exter-
nal components while keeping switching losses low.
The AAT1149B maintains high efficiency throughout the
operating range, which is critical for portable applica-
tions.
The AAT1149B 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 1.8V
• 400mA Max Output Current
• Up to 98% Efficiency
• 45μA 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
• 0.91 x 1.235mm 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
AAT1149B
IN
LX
EN
FB
AGND PGND
PGND PGND
V_OUT = 1.8V
L1 2.2µH
C1
4.7µF
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [e-mail] • www.skyworksinc.com
201989B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • March 18, 2013
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