LG C3400 Service Manual page 62

(4) Checking PAM Control Signal
TEST POINT
PA_EN (R502)
TX_RAMP (R509)
Waveform
Checking Flow
Check TX_RAMP and PA_EN
Check if there is
Any Major Difference or not
Refer to Graph 4-7
Checking Flow
VBAT
2
C507
22u
3p
BS
4
PAC_ENABLE
5
2
R503
GSM_IN
6
36
R504 R505
DCS_PCS_IN
150 150
5
R506
30
R507 R508
180 180
3 C506
0 01
TX_RAMP
PAM_EN
Graph 4-7
No
Similar?
Yes
Go to Next Step
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4. Troubleshooting
R501 100
GPO_17
PA_BAND
C501
27p
R502 100
GPO_16
PA_EN
RF2.85V RF2.85V
C509
27p
C532 C525
100p 22n
C516
1000p
Download S/W
26MHz
QP
C526 39p
QN
IP
C519 39p