AAT1146
Fast Transient 400mA Step-Down Converter
1146.2006.04.1.3 1
SwitchReg
™
General Description
The AAT1146 SwitchReg is a member of
AnalogicTech's Total Power Management IC™
(TPMIC™) product family. It is a 1.4MHz step-
down converter 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.
The AAT1146 is available in fixed voltage versions
with internal feedback and a programmable ver-
sion 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.
The AAT1146 is designed to maintain high efficien-
cy throughout the operating range, which is critical
for portable applications.
The AAT1146 is available in a Pb-free, space-saving
2.0x2.1mm SC70JW-8 package and is rated over
the -40°C to +85°C temperature range.
Features
•V
IN
Range: 2.7V to 5.5V
•V
OUT
Fixed or Adjustable from 0.6V to V
IN
•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
• 100% Duty Cycle Low-Dropout Operation
•<1μA Shutdown Current
• SC70JW-8 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 (Fixed Output Voltage)
4.7 µ H
L1
4.7 µ F
C1
4.7 µ F
C2
EN
1
OUT
2
VIN
3
LX
4
AGND
5
PGND
6
PGND
7
PGND
8
AAT1146
U1
V
IN
V
O