LG -C300 Service Manual page 64

(1) Checking Crystal Circuit
TEST POINT
Figure 4.2.1
CIRCUIT
Connect GND plane directly
Close to the 26MHz XTAL
X102 DSX321G-26M
4 3
1 2
2V85_VSIM
26MHz
TP1
C126
1 pin
0.1u
Figure 4.2.2
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Only for training and service purposes
X102
1 pin : 26MHz
NLB_AD25
H7
USIF2_RTS_N
J8
NUB
USIF2_CTS_N
A2
UART_TX
USIF1_TXD_MTSR
B3
UART_RX
USIF1_RXD_MRST
A3
BT_RXD
USIF1_RTS_N
B2
BT_TXD
USIF1_CTS_N
K11
USB_DP
DPLUS
K12
USB_DM
DMINUS
B11
XOX
A11
XO
M8
VSIM
G3
SIM_DATA
SIM_IO
G2
SIM_CLK
SIM_CLK
G4
SIM_RST
SIM_RST
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4. TROUBLE SHOOTING
4. TROUBLE SHOOTING
CHECKING FLOW
No
26 MHz O.K?
Yes
Crystal is OK.
See next page to check PLL Circuit
WAVEFORM
EINT2
CC1CC6IO
Figure 4.2.3
Replace X102
LGE Internal Use Only