AAT2550_08 Datasheet, PDF (13/34 Pages) Advanced Analogic Technologies – Total Power Solution for Portable Applications

SystemPower^TM
PRODUCT DATASHEET
AAT2550178
Total Power Solution for Portable Applications
Functional Block Diagram
ADP
ADPSET
ENBAT
STAT2
STAT1
CT
FBA
ENA
4.2V
Current
Compare
Constant
Current
Charge
Status
Watchdog
Timer
Err.
Amp.
Voltage
Reference
Control
Logic
Reverse Blocking
OTP UVLO
Charge
Control
CV/Pre-
Charge
Window
Comparator
80μA
DH
Logic
DL
FBB
ENB
Err.
Amp.
Voltage
Reference
Control
Logic
DH
Logic
DL
BAT
TS
INA
LXA
PGND
INB
LXB
PGND
Functional Description
The AAT2550 is a highly integrated power management
IC comprised of a battery charger and two step-down
voltage converters. The battery charger is designed for
charging single-cell lithium-ion / polymer batteries.
Featuring an integrated pass device and reverse block-
ing, it offers a constant current / constant voltage charge
algorithm with a user-programmable charge current
level. The two step-down converters have been designed
to minimize external component size and maximize effi-
ciency over the entire load range. Each converter has
independent enable and input voltage pins and can pro-
vide 600mA of load current.
Battery Charger
The battery charger is designed to operate with standard
AC adapter input sources, while requiring a minimum
number of external components. It precisely regulates
charge voltage and current for single-cell lithium-ion /
polymer batteries.
The adapter charge input constant current level may be
programmed up to 1A for rapid charging applications.
The battery charger features thermal loop charge reduc-
tion. In the event of operating ambient temperatures
exceeding the power dissipation abilities of the device
package for a given constant current charge level, the
2550.2008.02.1.3
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