Charger Troubleshooting; Only For Training And Service Purposes - LG KS20 Operating Instructions Manual

4. TROUBLE SHOOTING

4.11 Charger Troubleshooting

TA
VADP_5.0V
(4.8V)
VCHG_5.0V
USB
VUSB_5.0V
Cable
ISNS_P
ISNS_M
VPWR
Charging Procedure
- Connect TA or 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
- Battery
LGE Internal Use Only
TA OVP Circuit
NUS3065MUTAG
9
DRAIN_THERMAL
8
VCC
7
OUT
6
GATE
5
SRC
C313
1u
Battery Charging Circuit
U300
10
VBAT P_DRAIN
1
EMITTER1
2
EMITTER2
3
COLLECTOR
4
SOURCE
Current Flow
C305
C304
0.01u
22u
U302
1
IN
2
GND
FL300
3 1
CNTRL IN OUT
4 3
DRAIN G1 G2
NFM21PC105B1A3
NUS3116MTR2G
9
P_COLLECTOR
8
BASE1
7
BASE2
6
GATE
5
DRAIN
Charging
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
Copyright © 2007 LG Electronics. Inc. All right reserved.
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2
VCHG_5.0V
4
Pass Tr
CHG_CTL_N
(ON)
USB_CTL_N Pass Tr
(ON)
Battery FET
BAT_FET_N
(ON)
VBAT
Main
Battery

Only for training and service purposes