LG KG225 Service Manual page 48

(4) Checking PAM Control Signal
TEST POINT
U500
R502 (PAM_EN)
Figure 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 6
BS
1
ENABLE
18
SKY77328
U500 GSM_IN
4
DCS_PCS_IN
R503
3
(TX_RAMP)
C519 C520
0.01u 0.01u
R513
C522
39p
Graph 6
Similar? Similar? Similar?
Yes Yes Yes
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4. TROUBLE SHOOTING
CIRCUIT
VBAT
TX_RAMP
1K
No No No
Redownload S/W
R500 100
PA_BAND
R501 100
PA_EN
C505 C506
27p 27p