USB Port or AC Adapter
Lithium-Ion/Polymer Battery Charger
Typical Characteristics
Constant Charging Current
vs. Set Resistor Values
1000
350
300
AAT3681
Charging Current vs. Battery Voltage
(AAT3681 Only)
R
SET
= 5.36kΩ
R
SET
= 8.06kΩ
R
SET
= 16.2kΩ
I
CH
(mA)
I
CH
(mA)
100
250
200
150
100
50
10
1
0
R
SET
= 31.6kΩ
2.7
2.9
3.1
3.3
3.5
3.7
3.9
4.1
4.3
1
10
100
1000
R
SET
(kΩ)
Ω
V
BAT
(V)
Charging Current vs. Battery Voltage
(AAT3681-1 Only)
600
500
400
300
200
100
4.206
End of Charge Battery Voltage
vs. Supply Voltage
4.204
R
SET
= 3.24K
V
BAT_EOC
(V)
R
SET
= 8.06kΩ
I
CH
(mA)
4.202
4.200
4.198
4.196
4.194
R
SET
= 5.36K
R
SET
= 8.06K
R
SET
= 16.2K
R
SET
= 31.6kΩ
R
SET
= 31.6K
0
2.7
2.9
3.1
3.3
3.5
3.7
3.9
4.1
4.3
4.5
4.75
5
5.25
5.5
5.75
6
6.25
6.5
V
BAT
(V)
V
IN
(V)
End of Charge Voltage Regulation
vs. Temperature
(R
SET
= 8.06kΩ)
Ω
4.23
4.22
220
210
Constant Charging Current vs.
Supply Voltage
(R
SET
= 8.06kΩ)
Ω
V
BAT_EOC
(V)
I
CH
(mA)
4.21
4.20
4.19
4.18
4.17
V
BAT
= 3.3V
V
BAT
= 4V
200
190
180
170
V
BAT
= 3.6V
-50
-25
0
25
50
75
100
4
4.25
4.5
4.75
5
5.25
5.5
5.75
6
6.25
6.5
Temperature (°C)
V
IN
(V)
3681.2007.01.1.2
5
AAT [ ADVANCED ANALOG TECHNOLOGY, INC. ]
