- 89 -
Copyright © 2010 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
4. TROUBLE SHOOTING
GS290 Operational Description Revision B
LG Electronics
89/136
LGE Property
4.12.2. Checking PLL Control signals
Check U500
Yes
No
No
Yes
Control Signal is OK.
See next page to check
Mobile SW & FEM.
No
Yes
Checking Flow
Check U500
Check U500
TP1 (RF_EN)
TP3 (RF_CLK)
Checking Points
Figure 5. Transceiver
Figure 6. Transceiver Circuit
Waveform
RF Transceiver Circuit Diagram
EN Signal(TP1) is OK ?
DA(Data,TP2) is Normal ?
CLK(Clock,TP3) is Normal ?
TP2 (RF_DATA)
U601
TP2
TP3
TP1
RF_EN(TP1)
RF_CLK(TP2)
RF_DATA(TP3)
Figure 7. PLL Control Waveform
26MHz
X500
TSX-3225
2
1
3
4
GND2
HOT2
HOT1
GND1
U500
PMB6272
20
19
18
17
16
15
14
13
1
2
2
1
2
2
1
1
3
2
0
1
4
2
9
5
2
8
6
2
7
7
2
6
8
2
5
9
2
4
0
3
3
1
3
2
2
3
1
33
34
35
36
37
38
39
40
41
GND4
GND3
VDDMIX2V8
VDDTX2V8
TX2
TX1
VDDTX1V5
VBIAS
FE2
A
1
EF
X
A
8
V2
S
AI
B
D
D
V
B
X1
X
R
X
B
1
X
R
8
V2
GI
D
D
D
V
X2
X
R
A
D
2
X
R
KL
C
2
D
N
G
5
V1
GI
D
D
D
V
X3
X
R
3
S
Y
SF
3
X
R
2
S
Y
SF
X4
X
R
O
X
4
X
R
X
O
X
5
V1
A
NL
D
D
V
GND1
FSYS1
VDDXO2V8
EN
VDDVCO2V8
VCO_RC
VDDRX1V5
VDDRX2V8
1n
C516
C517
47n
0.1u
C535
0.1u
C506
R508
820
0.1u
C536
0.1u
C537
RF_EN
RF_DA
RF_CLK
26MHZ_MCLK
QX
Q
IX
I
CLK26M