Switching Charger Troubleshooting - LG -P895 Service Manual

4.10 Switching Charger Troubleshooting

a. Current flow
- LGP895 Charging scenario is stated from bottom side micro USB connector of LGP895. The charging current flows step
by step, USB connector on FPCB to over voltage protection IC (protect up to 28V, Max 14528) to charging IC(MAX 8971).
b. Charging current setting
- The charging current is set to max 900mA. The constant current period is set until voltage up to 4.2V. The constant
voltage period is ended up to cut-off current of 200mA.
uUSB 5 pin connector
CN6001
10 8
1
6 2
3
7 4
5
C6027
11 9
EAG63149901
CHARGER_IRQB
c. Charging current flow check point
- Micor USB connector
- Over protection IC
- Charging IC
- Battery
d. Charging Procedure
- Connect Travel Adaptor (Charging Cable) to Micro USB
connector.
-Current flow to OVP IC to be protected from over voltage
LGE Internal Use Only
VCHG
2mm
FL6000
1
IN OUT
GND1 GND2
C6024
C6023 C6025
22p
DNI DNI
Rev.B
FL6001
P1 P3
1 3
P2 P4
2 4
USB_ID
EAM62272401
ICMEF112P500MFR
22p
production Issue. under 1pF
CHARGING IC
VCHG_OVP USB_VBUS
+1V8_TPS_VIO
C6001
2.2u
25V
10V
Rev.B
4.7K -> 47K
PWR_I2C_SDA
C6016
PWR_I2C_SCL
1u
OVP_VCHG
VCHG
USB_DM
USB_DP
D1 C2
DC1 BST
D2
DC2
C1
BYP
D4
SFO
D3 B1
PVL LX1
D5 B2
AVL LX2
U6000
C3 A1
GND PG1
MAX8971EWP
A2
PG2
EAN62109401
A3
VICHG
B4 A4
I2CIN CS
B3 A5 R6005
IRQB BAT
C5 B5
SDA THM
C4
Charging current
SCL
- Current from OVP IC flows to Charging IC meanwhile,
MUIC indicate charger insertion
-Current from charging IC flows to system and battery
e. Troubleshooting Setup
- Connect TA to P895(with battery)
f. Troubleshooting Procedure
- -Check connection between TA(USB cable) and LGP895
- 76 - Copyright © 2012 LG Electronics. Inc. All right reserved.
4. TROUBLE SHOOTING
VCHG_OVP
U6001 MAX14528
2mm 2mm
1 7
IN1 OUT1
2 8
IN2 OUT2
C6012 C6013
4
IC1
0.1u 4.7u
3 5
50V
OVLO IC2
EUSY0374601
C6000
0.1u
L6000
C6002
1u
1u
C6006
1n
2012.04.27
VBAT
10V
Only for training and service purposes
10V
Battery
System