Only For Training And Service Purposes - LG GM200 Service Manual

(3) Checking RX I/Q
TEST POINT
TP3
TP4
Figure 4.2.3
WAVEFORM
CHECKING FLOW
Check C516, C517.
Check if there is any
Major difference
Refer to Graph 4.2.3
LGE Internal Use Only
Copyright © 2009 LG Electronics. Inc. All right reserved.

Only for training and service purposes

TP2
TP1
RX_I
TP3 & T43
RX_Q
TP1 & TP2
Similar?
Yes
Redownload software and calibration
- 75 -
CIRCUIT
C 5 0 9
2 2 0 n
C 5 1 4
1 u
V C C _ R E F
1 7
V A F C _ N C
1 8
R E F N I B
1 9
R E F N I
2 0
E U S Y
R E F _ O P
2 1
Q N Q B
2 2 A
C 5 1 6 Q
2 3
3 9 p
V C C _ B B Q
2 4
Q P
V L D O 1
Graph 4.2.3
No No
Replace U501
again
4. TROUBLE SHOOTING
V L D O 1
TP3 TP4
N C
8
S E N
7
S C L K
U 5 0 1
6
S D A T A
5
0 2 8 0 1 0 1
V C C _ B I B
4
B I
D 6 5 4 8 3
I C 5
2
V C C _ F E 3 9
1
LGE Internal Use Only
N I
1 7
p
P I