AAT2120 Datasheet, PDF (1/20 Pages) Advanced Analogic Technologies – 500mA Low Noise Step-Down Converter

AAT2120
500mA Low Noise Step-Down Converter
General Description
Features
SwitchReg^™
The AAT2120 SwitchReg is a 1.8MHz step-down
converter 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 AAT2120 the ideal choice for portable
applications.
The AAT2120 delivers up to 500mA of load current,
while maintaining a low 45µA no load quiescent cur-
rent. The 1.8MHz switching frequency minimizes
the size of external components, while keeping
switching losses low. The AAT2120 feedback and
control delivers excellent load regulation and tran-
sient response with a small output inductor and
capacitor.
The AAT2120 maintains high efficiency throughout
the load range. The AAT2120’s unique architecture
produces reduced ripple and spectral noise. Over-
temperature and short-circuit protection safeguard
the AAT2120 and system components from damage.
The AAT2120 is available in a Pb-free, 8-pin,
2x2mm STDFN package and is rated over the -40°C
to +85°C temperature range.
• V_IN Range: 2.7V to 5.5V
• V_OUT Range: 0.6V to V_IN
• Up to 500mA Output Current
• Up to 96% Efficiency
• Low Noise Light Load Mode
• 45µA Typical Quiescent Current
• 1.8MHz 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 STDFN22-8 Package
• Temperature Range: -40°C to +85°C
Applications
• Bluetooth^® Headsets
• Cellular Phones
• Digital Cameras
• Handheld Instruments
• Micro Hard Disk Drive
• Portable Music Players
• USB Devices
Typical Application
V_IN
C₁
4.7µF
AAT2120
VP
LX
VIN
EN
FB
GND PGND
V_O = 1.8V
L1
3.0μH
R₁
118kΩ
500mA
R₂
59kΩ
C₂
4.7µF
2120.2007.10.1.1
1