AAT2550 Datasheet, PDF (1/35 Pages) Advanced Analogic Technologies – Total Power Solution for Portable Applications

AAT2550
Total Power Solution for Portable Applications
General Description
Features
SystemPower^™
The AAT2550 is a fully integrated total power solu-
tion with two step-down converters plus a single-
cell lithium-ion / polymer battery charger. The step-
down converter input voltage range spans 2.7V to
5.5V, making the AAT2550 ideal for systems pow-
ered by single-cell lithium-ion/polymer batteries.
The battery charger is a complete constant current/
constant voltage linear charger. It offers an inte-
grated pass device, reverse blocking protection,
high current accuracy and voltage regulation,
charge status, and charge termination. The charg-
ing current is programmable via external resistor
from 100mA to 1A. In addition to these standard
features, the device offers over-voltage, over-cur-
rent, and thermal protection.
The two step-down converters are highly integrated,
operating at a switching frequency of 1.4MHz, mini-
mizing the size of external components while keep-
ing switching losses low. Each converter has inde-
pendent input, enable, and feedback pins. The out-
put voltage ranges from 0.6V to V_IN. Each converter
is capable of delivering up to 600mA of load current.
The AAT2550 is available in a Pb-free, space-sav-
ing, thermally-enhanced QFN44-24 package and is
rated over the -40°C to +85°C temperature range.
• Two Step-Down Converters:
— 600mA Output Current per Converter
— V_IN Range: 2.7V to 5.5V
— 1.4MHz Switching Frequency
— Low R_DS(ON) 0.4Ω Integrated Power
Switches
— Internal Soft Start
— 27µA Quiescent Current per Converter
• Highly Integrated Battery Charger:
— Programmable Charging Current from
100mA to 1A
— Pass Device
— Reverse Blocking Diodes
— Current Sensing Resistor
— Digital Thermal Regulation
• Short-Circuit, Over-Temperature, and Current
Limit Protection
• QFN44-24 Package
• -40°C to +85°C Temperature Range
Applications
• Cellular Telephones
• Digital Cameras
• Handheld Instruments
• MP3, Portable Music, and Portable Media
Players
• PDAs and Handheld Computers
Typical Application
Adapter
Serial Interface
R_SET
Li-Ion Battery or
Adapter
ADP
BAT
AAT2550
STAT1
TS
STAT2
DATA
CT
ADPSET
ENBAT
INA
INB
ENA
ENB
GND
LXA
FBA
LXB
FBB
Battery Pack
Batt+
Batt-
Temp
V _OUTA
C_OUTA
V_OUTB
C_OUTB
2550.2006.07.1.0
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