LG KE970 Service Manual page 103

5. Trouble shooting
5.11.12 Checking PAM Control Signals
GND25
27
GND24
28
GND23
29
GND22
30
GND21
31
GND20
32
GND19
33
GND18
34
GND17
U402
35
GND16
SKY77340
36
GSM_OUT
9
GND5
10
GND4
11
RSVD2
12
GND3
13
GND2
14
GND1
15
DCS_PCS_OUT
16
Checking Points
MODE
GMSK
8PSK
GND15
26
GND14
25
GND13
24
GND12
23
GND11
22
GND10
21 VSUPPLY
GND9
20
GND8
19
GND7
18
GND6
17
EN
8
GSM_IN
7
VRAMP
6
VBATT
5
RSVD1
4
BS
3
DCS_PCS_IN
2
MODE
1
C426 C427 C413 C428
68u
0.1u 1u 27p
MODE
LOW
HIGH
- 104 -
R405 1.2K
R406
C429 C430 C414 C431 C415
100p 100p 100p 820p 100p
TXON PA
PA LEVEL
MODE
PA_LEVEL TXON_PA
Ramp Burst Control HIGH
Control Amp bias HIGH
TXON_PA
LBAND_PAM_IN
PA_LEVEL
0
VBIAS
PA_BAND
HBAND_PAM_IN
MODE