Table of Contents
Advertisement
4.9.1. Checking DCXO Circuit
Checking Points
TP1(C438) : 26MHz
Figur2. DCXO
DCXO Circuit Diagram
1
7
E
N
1
6
V
D
D
X
O
2
V
8
1
5
F
S
Y
S
1
1
4
G
N
D
1
1
3
X
4
0
0
4
G
N
D
2
1
H
O
T
1
2
6
M
Figure 3. DCXO Cicuit
Figure 3. DCXO Cicuit
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
X40
C
4
1
0
TP1
N
X
3
2
2
5
S
A
3
H
O
T
2
2
G
N
D
1
H
z
TP1
I S
M
1
_
B
T
_
C
L
K
Checking Flow
Is the waveform
of TP1(C438) similar to Fig.4?
Yes
DCXO Circuit is OK.
See next page to check
PLL Circuit.
Waveform
R
F
_
E
N
3
6
2
6
M
H
Z
_
M
C
L
K
0
0
p
TP1 (C438)
Figure 4. DCXO Waveform
Figure 4. DCXO Waveform
- 83 -
4. TROUBLE SHOOTING
No
Replace X400
Waveform
TP1 (C438)
LGE Internal Use Only
Advertisement
Table of Contents
Troubleshooting
