AAT2550_08 Datasheet, PDF (1/34 Pages) Advanced Analogic Technologies – Total Power Solution for Portable Applications

SystemPower^TM
PRODUCT DATASHEET
AAT2550178
Total Power Solution for Portable Applications
General Description
The AAT2550 is a fully integrated total power solution
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 powered by single-cell lithi-
um-ion/polymer batteries.
The battery charger is a complete constant current/ con-
stant voltage linear charger. It offers an integrated pass
device, reverse blocking protection, high current accu-
racy and voltage regulation, charge status, and charge
termination. The charging current is programmable via
external resistor from 100mA to 1A. In addition to these
standard features, the device offers over-voltage, over-
current, and thermal protection.
The two step-down converters are highly integrated,
operating at a switching frequency of 1.4MHz, minimiz-
ing the size of external components while keeping
switching losses low. Each converter has independent
input, enable, and feedback pins. The output 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-saving,
thermally-enhanced QFN44-24 package and is rated
over the -40°C to +85°C temperature range.
Features
• Two Step-Down Converters:
▪ 600mA Output Current per Converter
▪ VIN Range: 2.7V to 5.5V
▪ 1.4MHz Switching Frequency
▪ Low RDS(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
2550.2008.02.1.3
www.analogictech.com
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