AAT3697IWP-4.2-T1 Advanced Analog Technology, Inc., AAT3697IWP-4.2-T1 Datasheet - Page 9

• Manufacturer Part Number: AAT3697IWP-4.2-T1
• Description: 2A Lithium-Ion/Polymer Battery Charger
• Manufacturer: Advanced Analog Technology, Inc.

Functional Block Diagram
Functional Description
The AAT3697 is a highly integrated single-cell lithi-
um-ion/polymer battery charger IC designed to
operate with standard AC adapter input sources,
while requiring a minimum number of external
components.
battery charge voltage and current for 4.2V lithium-
ion/polymer battery cells.
The adapter charge input constant current level
can be programmed up to 2.0A for rapid charging
applications. The AAT3697 is rated for operation
from -40°C to +85°C. In the event of operating
ambient temperatures exceeding the power dissi-
pation abilities of the device package for a given
constant current charge level, the charge control
will enter into thermal regulation. When the system
thermal regulation becomes active, the pro-
grammed constant current charge amplitude will
be automatically reduced to a safe level for the cur-
rent operating condition. Should the ambient oper-
ating temperature drop below the thermal loop
threshold, the system will automatically resume
charging at the full programmed constant current
3697.2007.02.1.1
The AAT3697 precisely regulates
ADPSET
ADPP#
STAT1
STAT2
DATA
ADP
EN
Voltage
4.2V
Sense
Charge
Status
Serial
Data
Constant
Compare
Current
Current
IC enable
2A Lithium-Ion/Polymer Battery Charger
GND
level. This intelligent thermal management system
permits the AAT3697 to operate and safely charge
a battery cell over a wide range of ambient condi-
tions while maximizing the greatest possible
charge current for the given set of conditions.
Status monitor output pins are provided to indicate
the battery charge state by directly driving two
external LEDs. A serial interface output is also
available to report any one of 12 distinct charge
states to the system microcontroller.
Battery 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, thus protecting
the charging device, control system, and the bat-
tery under charge. In addition to internal charge
controller thermal protection, the AAT3697 also
provides a temperature sense feedback function
(TS pin) from the battery to shut down the device in
the event the battery exceeds its own thermal limit
during charging. All fault events are reported to the
user either by the simple status LEDs or via the
DATA pin function.
Control
Charge
Reverse Blocking
Watchdog
Timer
Temperature
Protection
Precharge
Over-
UVLO
CV/
BAT
CT
TS
AAT3697
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