LG GD510 Service Manual page 79

5. Trouble shooting
GD510 Operational Description
5.12.2. Checking PLL Control signals
Checking Points
TP1 (RF_EN)
Figure 5. Transceiver
RF Transceiver Circuit Diagram
FE2
33
VBIAS
34
VDDTX1V5 VDDRX2V8
35 20
TX1 VDDRX1V5
U602
36 19
TX2 VCO_RC
PMB6272
37 18
VDDTX2V8 VDDVCO2V8
38 17
VDDMIX2V8 EN
39 16
GND3 VDDXO2V8
40 15
FSYS1
14
GND4 GND1
41 13
X601
4
GND2
1
HOT1
26MHz
Figure 6. Transceiver Circuit
LG Electronics
LGE Internal Use Only
TP3 (RF_CLK)
TP2 (RF_DATA)
U602
C650 C649 C623
100n 100n 100n
C627 47n
R603 820
RF_EN
C619 1n
26MHZ_MCLK
TP1
TP1
TSX-3225
3
HOT2
2
GND1
TP2
TP2
BT_CLK
TP3
RF_CLK
TP3
RF_DA
QX
Q
IX
I
Checking Flow
EN Signal(TP1) is OK ?
Yes
DA(Data,TP2) is Normal
Yes
CLK(Clock,TP3) is Normal
Yes
Control Signal is OK.
See next page to check
Mobile SW & FEM.
RF_DATA(TP3)
RF_CLK(TP2)
RF_EN(TP1)
Figure 7. PLL Control Waveform
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Revision A
No
Check U602
Check U602
No
No
Check U602
Waveform
LGE Property
Only for training and service purposes