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4. TROUBLE SHOOTING
- 69 -
LGE Internal Use Only
Copyright © 011 LG Electronics. Inc. All right reserved.
Only for training and service purposes
(1) Checking Crystal Circuit
Figure 4.2.1
26 MHz O.K?
No
Crystal is OK.
See next page to check PLL
Circuit
Yes
Replace X201
Figure 4.2.2
Figure 4.2.3
TP1
TP1
TEST POINT
CIRCUIT
WAVEFORM
CHECKING FLOW
X102
TP1_1 pin :
26MHz
X201
TSX-3225
2
1
3
4
26MHz
GND2
HOT2
HOT1
GND1
VSIM_PWR
0.1u
C231
G5
F2
F3
F1
D2
D1
E2
M10
A13
B13
K14
K13
B4
A5
B5
A4 USIF1_TXD_MTSR
USIF1_RXD_MRST
USIF1_RTS_N
USIF1_CTS_N
DPLUS
DMINUS
XOX
XO
VSIM
SIM_IO
SIM_CLK
SIM_RST
MMCI_CMD
MMCI_DAT_0
MMCI_CLK
USB_DP
USB_DM
UART_TX
SIM_DATA
SIM_CLK
MSD_CLK
MSD_D[0]
MSD_CMD
BT_UART_TX
BT_UART_RX
UART_RX
SIM_RST_N
Connect GND plane directly
Close to the 26MHz XTAL
TP1