AAT3683 Datasheet, PDF (10/24 Pages) Advanced Analogic Technologies – 1A Linear Li-Ion Battery Charger

Functional Block Diagram
AAT3683
1A Linear Li-Ion Battery Charger
Reverse Blocking
IN
BAT
Current
Compare
CV/ Pre-
charge
ISET
Constant
Current
ADPP#
(3683-2/-3 only)
Power
Detection
Charge
Control
75μA
(3683-2 only)
TS
IC Enable
Watchdog
Window
Timer
Comparator
UVLO
Over-
Temp.
Protect
Battery OV
Protection
Thermal
Loop
Charge
Status
STAT (3683-2/-3 only)
STAT1 (3683-4 only)
STAT2 (3683-4 only)
EN
CT
GND
Functional Description
The AAT3683 is a high performance battery charg-
er designed to charge single-cell lithium-ion or lithi-
um-polymer batteries with up to 1A of current from
an external power source. It is a stand-alone
charging solution, with just one external compo-
nent required for complete functionality.
The AAT3683 precisely regulates battery charge
voltage and current for 4.2V lithium-ion/polymer
battery cells with constant current level being pro-
grammed up to 1A for rapid charging applications.
The charge termination current can be pro-
grammed by an external resistor.
The AAT3683 is rated for operation from -40°C to
+85°C. In the event of operating ambient tempera-
tures exceeding the power dissipation abilities of the
device package for a given constant current charge
level, the charge control will enter into thermal limit.
10
AAT3683-2 and -3 provide one status monitor out-
put pin (STAT) by directly driving one external LED
to indicate the battery charging state. AAT3683-4
provides two status pins to indicate the battery
charging state.
Device junction temperature and charge state are
fully monitored for fault conditions. In the event of
an over-voltage or over-temperature failure, the
device will automatically shut down, protecting the
charging device, control system, and the battery
under charge.
During battery charging, the device temperature will
rise. In some cases with adapter (ADP) charging,
the power dissipation in the device may causethe
junction temperature to rise to close to its thermal
shutdown threshold. In the event of an internal
over-temperature condition caused by excessive
ambient operating temperature or excessive power
dissipation condition, the AAT3683 enables a digi-
3683.2007.06.1.0