Power Management Low-Cost, Two-Cell Li-Ion/Li-Pol Battery Charger with Cell-Balancing Support Specification Sheet

AN2309
November 25, 2007 Document No. 001-17394 Rev. *B - 7 -
Figure 4. Two-Cell Battery Charger Schematic – CPU, Cell Balancing, and Measuring Equipment
BAL2
Q1
IRLML6402
BAL1
CALIBRATION
DRIVE
1
2
3
4
5
J2
ISSP/DEBUG
XRES
VCC
TX
TP1
BAL1
Vref
P0[7]
1
P0[5]
2
P0[3]
3
P0[1]
4
P2[7]
5
P2[5]
6
P2[3]
7
P2[1]
8
SMP
9
P1[7]
10
P1[5]
11
P1[3]
12
P1[1]
13
Vss
14
P1[0]
15
P1[2]
16
P1[4]
17
P1[6]
18
Xres
19
P2[0]
20
P2[2]
21
P2[4]
22
P2[6]
23
P0[0]
24
P0[2]
25
P0[4]
26
P0[6]
27
Vcc
28
U1
CY 8C24423A
VCC
V1
V2
Vi2
Vbias R24
10K 1%
LED_GREEN
R16
1M 1%
R15
1M 1%
R21
200K 1%
R20
200K 1%
C8 0.1u
Vi1
Vi2
Vi1
R14
100
C6
0.01u
R17
1M
R13 150K 0.1%
R12
50K 0.1%
V1
Q5
IRLML2502
Vref
C5
0.01u
R7 150K 0.1%
R6
50K 0.1%
V2
1
2
3
4
5
J1
BAT_CON
C7
0.01u
R18 150K 0.1%
BAT_GND
R19
50K 0.1%
R23
100mOh 1%
Vbias
BAT_GND
Vbias
POWER-
BAT+
BAT2
Vref
Tbat
BAT1
GND
TERMO
LED_Y ELLOW
Tbat
DRIVE
LOAD_EN
Q4
IRLML6402
R8
1M
XRES
R22
10K
R11
100
+
C2
47uF
R5
15K
R1
10K
C1
0.01uF
D1
MBR360C3
1uF CER
POWER+
Q2
BC817
C4
0.1uF
R4 1K
R9
330R
Q3
BC817
R10
10K
BAL2
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