PRODUCT DATASHEET
AAT2785
SystemPower
TM
General Description
The AAT2785 is a 3-channel 1.8MHz step-down con-
verter for applications where power efficiency and solu-
tion size are critical. The input voltage range is 2.7V to
5.5V and the outputs are adjustable from 0.6V to V
IN
.
The AAT2785 incorporates a unique low noise architec-
ture which reduces ripple and spectral noise. Channel 3
delivers up to 1.5A output current and channels 1 and 2
deliver up to 600mA each. The AAT2785 uses a high
switching frequency to minimize the size of external com-
ponents. The AAT2785 requires a minimum of external
components to realize a high efficiency triple-output buck
converter minimizing solution cost and PCB footprint.
Each of the 3 regulators has an independent enable pin,
adjustable output voltage and operates with low no load
quiescent current, providing high efficiency over the
entire load range.
The AAT2785 is available in a Pb-free 16 pin TDFN34
package, and is rated over the -40°C to +85°C operating
temperature range.
3-Channel Step-Down DC/DC Converter
Features
• V
IN
Range: 2.7 to 5.5V
• Output Voltage Range: 0.6V to V
IN
• Output Current:
▪
Channel 3: 1.5A
▪
Channel 1: 600mA
▪
Channel 2: 600mA
• Low Noise Light Load Mode
• Low Ripple PWM Mode
• Highly Efficient Step-Down Converters
• Low R
DS(ON)
Integrated Power Switches
• 100% Duty Cycle
• 1.8MHz Switching Frequency
• Internal Soft Start
• Fast 150μs Turn-On Time
• Over-Temperature Protection
• Current Limit Protection
• TDFN34-16 Package
• -40°C to 85°C Temperature Range
Applications
•
•
•
•
•
•
•
•
•
Cellular and Smart Phones
Digital Cameras
Handheld Instruments
Mass Storage Systems
Microprocessor / DSP Core / IO Power
PDAs and Handheld Computers
Portable Media Players
USB Devices
Wireless LAN
Typical Application
IN
LX1
L1
4.7μH
V
OUT1
: 3.3V, 600mA
R1
133k
AAT2785
FB1
V
IN
: 2.7V–5.5V
VP1_2
EN1
LX2
FB2
C1
10μF
EN2
PGND
L3
1.5μH
VP3
EN3
FB3
C2
10μF
GND
PGND
LX3
L2
4.7μH
V
OUT2
: 3.3V, 600mA
R3
133k
R4
29.4k
C4
4.7μF
R2
29.4k
C3
4.7μF
V
OUT3
: 1.2V, 1.5A
R5
59.0k
R6
59.0k
C5
10μF
2785.2008.01.1.0
www.analogictech.com
1
ANALOGICTECH [ ADVANCED ANALOGIC TECHNOLOGIES ]
