DATA SHEET
AAT1145
1.5A Step-Down Converter
General Description
Features
The AAT1145 SwitchReg™ is a 1.2MHz constant fre-
quency current mode PWM step-down converter. It is
ideal for portable equipment requiring very high current
up to 1.5A from single-cell Lithium-ion batteries while
still achieving over 90% efficiency during peak load con-
ditions. The AAT1145 also can run at 100% duty cycle
for low dropout operation, extending battery life in por-
table systems while light load operation provides very
low output ripple for noise sensitive applications.
• Input Voltage Range: 2.5V to 5.5V
• Output Voltages from 0.6V to VIN
• 1.5A Output Current
• High Efficiency: Up to 95%
• 1.2MHz Constant Switching Frequency
• Low RDS(ON) Internal Switches: 135mΩ, 95mΩ
• Allows Use of Ceramic Capacitors
• Current Mode Operation for Excellent Line and Load
Transient Response
• Short-Circuit and Thermal Fault Protection
• Soft Start
• Low Dropout Operation: 100% Duty Cycle
• Low Shutdown Current: ISHUTDOWN < 1μA
• TDFN33-10 Package
The AAT1145 can supply up to 1.5A output load current
from a 2.5V to 5.5V input voltage and the output voltage
can be regulated as low as 0.6V. The high switching fre-
quency minimizes the size of external components while
keeping switching losses low. The internal slope compen-
sation setting allows the device to operate with smaller
inductor values to optimize size and provide efficient
operation.
• -40°C to +85°C Temperature Range
Applications
The AAT1145 is available in adjustable (0.6V to VIN) and
fixed (1.8V) output voltage versions. The device is avail-
able in a Pb-free, 3 x 3mm 10-lead TDFN package and is
rated over the -40°C to +85°C temperature range.
• Cellular Phones
• Digital Cameras
• DSP Core Supplies
• PDAs
• Portable Instruments
• Smart Phones
Typical Application
L1
2.2μH
VOUT
1.8V,1.5A
VIN 2.5V-5.5V
1
8
LX
LX
EN
2
7
5
IN
C2
22μF
C1
10μF
3
AAT1145-1.8
AIN
OUT
10
9
6
4
AGND
AGND
PGND
PGND
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
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201984B
• Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • March 18, 2013