LG KS660 - Page 104

- 105 -
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Only for training and service purposes
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4. TROUBLE SHOOTING
4.12.3. Checking TX I/Q Signals
Checking Points
TX I/Q
I
Q
I
Q
TX I/Q Waveform
U401
TX
TP1(I)
TP2(IX)TP3(Q)
TP4(QX)
TX I/Q Circuit
Check TX I/Q Signals(TP1~TP4)
Signals are
Normal ?
Replace
Transceiver
PMB6272(U401
Yes
No
TX Part is OK.
Check Base Band Circuit
or
Re-Download S/W and Cal
Checking Flow
TP4(QX)
TP3(Q)TP2(IX)
TP1(I)
Check TX I/Q Signals(TP1~TP4)
Signals are
Normal ?
Replace
Transceiver
PMB6272(U401)
Yes
No
TX Part is OK.
Check Base Band Circuit
or
Re-Download S/W and Cal
Checking Flow
5
3
4
C
n
7
4
u1.
0
134
C
1TO
H
2
T
OH
3
2
34C
u
1
.0
z
HM6
2
A
S
5
2
2
3
XN
00
4X
2
1DNG
2DNG
4
1
u1.0
334C
FR
V_5
8
V
2
F
R
V
_5V1
VDDBIAS2V8
31
VDDDIG1V5
8 5
VDDDIG2V8
VDDLNA1V5
21
9
3
8V
2
X
I
M
D
D
V
9
1
5V1
X
R
DDV
8
V
2
X
R
D
D
V
0
25
3
5
V
1
XTDD
V
8
V
2X
TDDV
8
371
8
V
2OC
V
D
D
V
5
1
8V2O
X
D
D
V
11
XO XOX
12
1
D
NG
3
1
26
GND2
3
D
N
G
0
4
1
4
4
D
N
G
RX1
29 30
RX1X
RX2
27 28
RX2X
24
RX3
RX3X
25 22
RX4
RX4X
23
1
X
T
63
2
XT
73
SAIBV
4
3
8
1
C
R
_OCV
1
A AX
2 3
B BX
4 7
CLK DA
6
N
E
6
1
32
FE1
3
3
2
EF
1S
YS
F
41
FSYS2
10
9
FSYS3
2
72
6
B
M
P
2
0
4
U
0
2
8
7
0
4R
TS
E
T_TUO_M
6
2
I
X
I
Q
XQ
K
LC_
F
R
AD_
F
R
K
L
C
_
T
B
_
1
MIS
TP1(I)
TP2(IX)
TP4(QX)
TP3(Q)
TX I/Q Circuit