LG KP500 Service Manual page 96

5.14.2 Checking PLL Control signals
Checking Points
TP1 (RF_EN)
Figure 5. Transceiver
RF Transceiver Circuit Diagram
F 2 E
3 3
V I B S A
4 3
D V T D 1 X 5 V D V D R 2 X
U601
5 3
T 1 X D V D R 1 X
PMB6272
6 3
T 2 X C V O
EUSY0274801
7 3
D V T D 2 X 8 V D V D C V 2 O
8 3
D V D I M 2 X 8 V
9 3
G N 3 D D V D X 2 O
0 4
F Y S
G N 4 D G
1 4
VRF_2V85
X600 TSX- 3225
4
GND2
1 HOT1
6 C 2 4
. 0 u 1
Figure 6. Transceiver Circuit
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
TP3 (RF_CLK)
TP2 (RF_DATA)
U601
6 C 4 3 6 C 5 3 6 C 6 3
. 0 u 1 . 0 u 1 . 0 u 1
8 V
0 2
5 V
9 1
R _ C
8 1
8 V
7 1
N E
6 1
8 V
5 1
1 S
4 1
6 C 8 3 1 0 0 p 0
N 1 D
3 1
6 R 7 0 6 C 0 4
8 0 2 4 n 7
HOT2 3
2
GND1
26MHz
6 2 _ M T B
F R C _ K L
F R D _ A
Q X
Q
X I
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.
6 C 7 3
. 0 u 1
RF_DATA(TP3)
R _ F N E
6 2 M Z H M _ C K L
RF_CLK(TP2)
RF_EN(TP1)
Figure 7. PLL Control Waveform
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5. Trouble shooting
No
Check U601
Check U601
No
?
No
Check U601
?
Waveform
LGE Internal Use Only