AAT1121 Datasheet, PDF (1/19 Pages) Advanced Analogic Technologies – 1.5MHz, 250mA Step-Down Converter

General Description
The AAT1121 SwitchReg is a 1.5MHz step-down con-
verter with an input voltage range of 2.7V to 5.5V and
output as low as 0.6V. Its low supply current, small size,
and high switching frequency make the AAT1121 the
ideal choice for portable applications.
The AAT1121 delivers 250mA of load current, while
maintaining a low 30μA no load quiescent current. The
1.5MHz switching frequency minimizes the size of exter-
nal components, while keeping switching losses low. The
AAT1121 feedback and control delivers excellent load
regulation and transient response with a small output
inductor and capacitor.
The AAT1121 is available in a Pb-free, 8-pin, 2x2mm
TDFN or STDFN package and is rated over the -40°C to
+85°C temperature range.
DATA SHEET
AAT1121
1.5MHz, 250mA Step-Down Converter
Features
• V_IN Range: 2.7V to 5.5V
• V_{OUT Range: 0.6V to VIN}
• 250mA Max Output Current
• Up to 96% Efficiency
• 30μA Typical Quiescent Current
• 1.5MHz Switching Frequency
• Soft-Start Control
• -Over-Temperature and Current Limit Protection
• 100% Duty Cycle Low-Dropout Operation
• <1μA Shutdown Current
• Small External Components
• Ultra-Small TDFN22-8 or STDFN22-8 Package
• Temperature Range: -40°C to +85°C
Applications
• Bluetooth™ Headsets
• Cellular Phones
• Digital Cameras
• Handheld Instruments
• Portable Music Players
• USB Devices
Typical Application
V_IN
C₁
4.7µF
AAT1121
VP
LX
VIN
EN
FB
GND PGND
V_O = 1.8V
L1
3.0μH
R₁
118kΩ
250mA
R₂
59kΩ
C₂
4.7µF
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [e-mail] • www.skyworksinc.com
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201974B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • March 15, 2013