LG HB620 - Checking VCTCXO Block

- 107 -
4. TROUBLE SHOOTING
4.13 Checking VCTCXO Block
The reference frequency (19.2MHz) from X100 (VCXO) is used UMTS TX part, GSM part and BB part.
LGE Internal Use Only Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
TCXO
VREG_TCXO_2.85V
VREG_BT_2.85V
1000p
C149
100K
R116
TC7SH04FS
U103
1000pC148
X101
2
GNDOUT
3
VCC
4
VCONT
1
19.2MHz
0.01u
C145
100pC153C152 1000p
0.1u
C143
1000p
C144
TRK_LO_ADJ
TCXO_BT
TCXO_PM
TCXO_OUT
[Fig. 4.9] Schematic of the TCXO Block
[Fig. 4.10] Test Point of the TCXO Block
TP1TP1 TP2
TP4
TP3
Z3X-BOX.COM