LG KP170 - Page 49

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4. TROUBLE SHOOTING
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(3) Checking PAM Control Signal
ASM+PAM
C506
(Tx_RAMP)
C502
(PA_EN)
VBAT
56p
C503
GND2
9
GND3
10
12
GND4 GND5
13
GND6
14
GND7
15
16
GND8
20
GND9
17
GSM_IN
GSM_RX
7
18
NC
PGND
21
4
TX_EN
VBATT
1
2
VLOGIC
VRAMP
3
U501
SKY77518
ANT
11
BS
5
19
DCS_IN
DCS_RX
6
8
GND1
C508
10u
56p
C500
68p
C501
C510
0.01u
68
R503
56p
C502
PA_BAND
PA_EN
ANT_SW
TX_RAMP
TEST POINT CIRCUIT
WAVEFORM
Similar?
Yes
No
Check TX_RAMP and PAM_EN
Any Major Difference or not
¨
Similar?
Go to Next Step
Similar?
Re-downl oad
S/W
Check if there is
Any Major Difference or not
¨
Refer to Graph 4.3.3
Graph 4.3.3
Figure 4.3.3
CHECKING FLOW