Only For Training And Service Purposes - LG GB220 Service Manual

(1) Checking Crystal Circuit
TEST POINT
Figure 4.2.1
CIRCUIT
X100
FA-20H
EXXY0026401
4
GND
1 TER1
26MHz
2V85_VSIM
1 pin
Figure 4.2.2
LGE Internal Use Only
Copyright © 2009 LG Electronics. Inc. All right reserved.

Only for training and service purposes

X100
1 pin : 26MHz
UART_TX
UART_RX
nLCD_RESET
3
EOC
XTAL
2
USB_P
TER2
USB_N
SIM_DATA
SIM_CLK
SIM_RST
CHECKING FLOW
26 MHzO.K?
Yes
Crystal is OK. See next page to
check PLL Circuit
WAVEFORM
Figure 4.2.3
Copyright © 2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes
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4. TROUBLE SHOOTING
No
Replace X100
LGE Internal Use Only