LG S5000 Service Manual page 60

(4) Checking PAM Control Signal
Test Points
U500
R501 (PAM_EN)
Figure 4-9
Waveform
Checking Flow
Check TX_RAMP and PA_EN Check TX_RAMP and PA_EN
Check if there is Check if there is
Any Major Difference or not Any Major Difference or not
Refer to Graph 4 - 7 Refer to Graph 4 - 7
VBAT
C552
2.7p
C554
1000p
1
DCS_PCS_IN
R502
7
U500 GSM_IN
AWT6171R
3
TX_EN
(TX_RAMP)
2
BS
Graph 4-6
Similar? Similar? Similar?
Yes Yes Yes
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4. TROUBLE SHOOTING
CIRCUIT
C504
27p
C515 10p
R507 12
RF2V85 2V8_VEXT
R508
R509
430 430
C517 C518 C519
No No No
Redownload S/W
R500 0
PA_BAND (GPO_17)
R501 0
PA_EN (GPO_16)
R502 10K
TX_RAMP
C505 C506
1000p 1000p