Lithium-Ion/Polymer Battery Charger
Pin Descriptions
Pin #
1
2
3
4
AAT3687
Name
BAT
ADP
GND
EN
Type
Out
In
Ground
In
Function
Battery charging and sensing.
Adapter input.
Ground connection.
AAT3687: Enable pin. Logic high enables the IC.
AAT3687-1, AAT3687-2: Enable pin. Logic high enables the IC. EN tied to
internal 4MΩ pull-up resistor to ADP.
Adapter present indicator. This pin is open drain until ADP pin reaches
threshold.
Connect to 10kΩ NTC thermistor.
Status report to microcontroller via serial interface: open drain.
Battery charge status indicator pin to drive an LED: active low, open drain.
Battery charge status indicator pin to drive an LED: active low, open drain.
Timing capacitor to adjust internal watchdog timer. Set maximum charge
time for adapter powered trickle, CC, and CV charge modes. If timing
function is not needed, terminate this pin to ground.
No connection.
Use resistor at this pin to set adapter charging current.
Exposed paddle (bottom); connect to GND directly beneath package.
5
6
7
8
9
10
ADPP#
TS
DATA
STAT2
STAT1
CT
Out
In/Out
Out
Out
Out
In/Out
11
12
EP
N/C
ADPSET
In/Out
Pin Configuration
TDFN33-12
(Top View)
BAT
ADP
GND
EN
ADPP#
TS
1
2
3
4
5
6
12
11
10
9
8
7
ADPSET
N/C
CT
STAT1
STAT2
DATA
2
3687.2006.10.1.7
AAT [ ADVANCED ANALOG TECHNOLOGY, INC. ]
