PRODUCT DATASHEET
AAT1146
SwitchRegTM
FastTransient 400mA Step-Down Converter
General Description
Features
The AAT1146 SwitchReg is a 1.4MHz step-down con-
verter with an input voltage range of 2.7V to 5.5V and
output voltage as low as 0.6V. It is optimized to react
quickly to a load variation.
• VIN Range: 2.7V to 5.5V
• VOUT Fixed or Adjustable from 0.6V to VIN
• 27μA No Load Quiescent Current
• Up to 98% Efficiency
• 400mA Max Output Current
• 1.4MHz Switching Frequency
• 120μs Soft Start
• Fast Load Transient
• Over-Temperature Protection
• Current Limit Protection
The AAT1146 is available in fixed voltage versions with
internal feedback and a programmable version with
external feedback resistors. It can deliver 400mA of load
current while maintaining a low 27μA no load quiescent
current. The 1.4MHz switching frequency minimizes the
size of external components while keeping switching
losses low.
• 100% Duty Cycle Low-Dropout Operation
• <1μA Shutdown Current
The AAT1146 is designed to maintain high efficiency
throughout the operating range, which is critical for por-
table applications.
• SC70JW-8 and SOT23-5 Packages
• Temperature Range: -40°C to +85°C
The AAT1146 is available in the Pb-free, space-saving
2.0x2.1mm SC70JW-8 and SOT23-5 packages and is
rated over the -40°C to +85°C temperature range.
Applications
• Cellular Phones
• Digital Cameras
• Handheld Instruments
• Microprocessor / DSP Core / IO Power
• PDAs and Handheld Computers
• USB Devices
Typical Application (Fixed Output Voltage)
U1
AAT1146
L1
VO
VIN
LX
OUT
VIN
4.7µH
EN
C2
4.7µF
C1
4.7µF
PGND
PGND
AGND
PGND
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