Charger Troubleshooting - LG GD88O Service Manual

4. TROUBLE SHOOTING

4.11 Charger Troubleshooting

VCHG_VBUS
2mm
G2
4
OUT
2
FL400
NFM21PC105B1A3
2mm(to the GSM PAM)
2mm(to the Batt. Conn.)
Charging Procedure
- Connect TA or u-USB Cable
- Control the charging current by PM7540 IC
- Charging current flows into the battery
Check Point
- Connection of TA or USB Cable
- Charging current path(NUS5530)
- Battery
LGE Internal Use Only
IC2
5
IC1
4
U404
G1
3
MAX14528
OUT2
8
IN OUT1
1 7
1uF
MAX_DM
MAX_DP
Route together from both end of resistor 0.1ohm.
ISNS_P
ISNS_M
+VPWR
+VPWR
VBATT
Main
Main
C455
39p
Battery
Battery
Charging Current Flow
4. Troubleshooting
OVP
change circuit at REV B
OVLO
3
2mm
IN2
2
IN1
1
C457 C444
1u 22p
Close by uUSB CONN
USB_ID
D401
U403 NUS5530MN
DRAIN_B
1
1%
NC1 COLLECTOR_B
2
COLLECTOR EMITTER
3
SOURCE BASE
4
DRAIN NC2
GATE
C448
33uF
Troubleshooting Setup
- Connect TA and battery to the phone
Troubleshooting Procedure
- Check the charger (TA or USB Cable) connector
- Check the OVP Circuit
- Check the charging current Path
- Check the battery
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Copyright © 2010 LG Electronics. Inc. All right reserved.
(BB)
uUSB 5pin
CN400
6
8
10
12
14
1
TA
TA
2
(5.1V)
3
(5.1V)
4
5
7
9
11
13
15
Close by uUSB CONN
HSMU-5SB-24DR2
VCHG_VBUS
2mm
10
9
8
7
CHG_CTL_N
6
5
BATT_FET_N
Only for training and service purposes