4. TROUBLE SHOOTING
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Only for training and service purposes
LGE Internal Use Only
4.10 Switching Charger Troubleshooting
a. Current flow
- LGP880 Charging scenario is stated from bottom side micro USB connector of LGP880. 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 4.35V. The constant
voltage period is ended up to cut-off current of 200mA.
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
- 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 P880(with battery)
f. Troubleshooting Procedure
- Check connection between TA(USB cable) and P880
U13007 MAX14528
9
6
5
3
4
8
2
7
1
IN1
OUT1
IN2
OUT2
IC1
OVLO
IC2
GN
D
PGND
VCHG_OVP
0.1u
C6026
VCHG
C6027
4.7u
2mm
10V
50V
2mm
OVP_VCHG
VCHG_1
IN
OUT
GND1 GND2
6
7
8
1
2
3
4
5
9
10
11
USB_DP
USB_DM
USB_ID
uUSB 5 pin connector
2mm
Battery
System
1n
C6029
0.1u
C6006
L6000
1u
VBAT
U6000
C5
D2
D3
D1
A5
B5
A1
C1
B1
A4
A3
A2
D5
D4
C4
C3
C2
B2
B3
B4 I2CIN
IRQB
LX2
BST
GND
SCL
SFO
AVL
PG2
VICHG
CS
LX1
BYP
PG1
THM
BAT
DC1
PVL
DC2
SDA
R6014
47
m
VCHG_OVP
C6009
1u
1u
C6010
+1V8_TPS_VIO
C6008
1u
4.7u
C6028
C6007
2.2u
2.2u
C6016
R6004
4.7K
C6015
1u
USB_VBUS
PWR_I2C_SDA
PWR_I2C_SCL
CHARGER_IRQB
25V
CHARGING IC
10V
10V