LG LG-P350 - Checking TCXO Block

4. TROUBLE SHOOTING
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Only for training and service purposes
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4.3 Checking TCXO Block
The output frequency (19.2MHz) of TCXO (X200) is used as the reference one of RTR6285 and PM7540 internal
VCO.
G
G
G
G
G
G
Schematic of the Crystal Part (19.2MHz)
TP3
TP2
TP1
TP2
TP3
TP1
C308
10n
R310 33
100
R303
19.2MHz
KT3225L19200DCW28RA0
X300
42
31
VCONT OUT
GND VCC
C301
0.1u
C320
330p
C307
330p
R319
1
C309
330p
C300
1n
VREG_TCXO_2.85V
VREG_MSMA_2.6V
C310
0.1u
U301
3
2
4
1
5
VCC
GND
R311 100K
TCXO_PM_19.2MHZ
TCXO_EN
TCXO_RTR_19.2MHZ
USBH_SYSCLK
RTR_TRK_LO_ADJ
FFA Rev.C(220Ohm@100MHz)
1.0T
TCXO Circuit
Clesed to TCXO
TP2
TP1
TP3