LG CU920 - WCDMA RF Signal Path Analysis

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4. TROUBLE SHOOTING
4.5 Checking VCTCXO Block
The reference frequency (19.2MHz) from X101 (TCXO) is used in UMTS TX part, GSM part and BB
part
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Only for training and service purposes
TCXO
R123
100ohm
4
VCC
1
VCONT
TG-5010LH_19_2M_75A
X100
19.2MHz
GND
2
OUT
3
C157
33p
C160 100p
100pC166
0.1uF
C156
C161 1000p
0.01u
C158
1000pC164
RBR1000_TCXO
VREG_TCXO_2.85V
TCXO_BT
RFR6275_TCXO
TRK_LO_ADJ
TCXO_PM
RTR6275_TCXO
Fig. 4.5.1 Schematic of the TCXO Block
Fig, 4.5.2 VCTCXO 19.2MHz Wave
TP1
TP2
TP5
TP3
TP6
TP4