Checking Tcxo Block - LG -P350 Service Manual

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.
TCXO Circuit
R303
RTR_TRK_LO_ADJ
100
Clesed to TCXO
TP2
LGE Internal Use Only
TP3
X300
TP2
1 3
VCONT OUT
2 4
C308
GND VCC
10n
19.2MHz
KT3225L19200DCW28RA0
1.0T
Schematic of the Crystal Part (19.2MHz)
TP2
TP1
TP1
VREG_TCXO_2.85V
C300 C301
1n 0.1u
C307 330p
C309 330p
TP3
FFA Rev.C(220Ohm@100MHz)
R319
VREG_MSMA_2.6V
1
1
TCXO_EN
C320 330p 2
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4. TROUBLE SHOOTING
TP1
TCXO_PM_19.2MHZ
TCXO_RTR_19.2MHZ
TP3
C310
0.1u
5
VCC
4
R310 33
U301
GND
3
R311 100K
Only for training and service purposes
USBH_SYSCLK