4. TROUBLE SHOOTING
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Copyright © 2012 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
4.11 Charging Trouble Shooting
1. Charging Procedure
- Connect TA or u-USB Cable
- Control the charging current by LP8727-B IC
- Charging current flows into the battery
2. Check Point
- Connection of TA or USB Cable
- Charging IC (LP8727-B)
- Battery
3. Troubleshooting Setup
- Connect TA and battery to the phone
4. Troubleshooting Procedure
- Check the charger (TA or USB Cable)
- Check the OVP Circuit
- Check the Charging IC
C809
1n
D802
D803
D804
CN801
6
7
8
1
2
3
4
5
9
10
11
C807
22p
ZD800
FL800
IN
OUT
GND1
GND2
FL801
P2
P4
P1
P3
6
P
5
P
uUSB_POWER
MAX_DP
MAX_DM
USB_ID
MICRO USB IO
TA (5.1V / 705mA)
K0
1
82
5
R
76
5
C
u1
C575
1u
C566
1u
TP400
U506
C5
D2
B5
D3
D1
E1
E2
E3
E5
E4
A1
C1
B1
A4
A5
A3
A2
D5
4
D
4
C
3
C
2
C
2
B
3
B
4
B
L
C
S
A
D
S
¬
¡
T
N
I
1
D
N
G
2
D
N
G
3
D
N
G
4
D
N
G
BATT2
DN
DP
U1
U2
AUD1
AUD2
MIC
VBUS1
VBUS2
D-
D+
ID
RES
DSS
EXPDET
CAP
BATT1
VREG_MSME_1.8V
K7.
4
92
5
R
03
5
R
K7.
4
56
5
C
u1
C564
1u
C576
1u
GND
VBAT
uUSB_POWER
VREG_MSME_1.8V
UART_TX
UART_RX
USB_ID
VCHG_VBUS
MAX_DM
MAX_DP
USBH_DM
MINIABB_I2C_SDA
MINIABB_I2C_SCL
MINIABB_INT
USBH_DP
Mini ABB_NS
TA
Battery