LG GD310 Service Manual page 99

5. TROUBLE SHOOTING
5.13.5. Checking PAM Control Signals
TP2(TXON PA)
TP2(TXON PA)
PGND
15
GND3
8
GND2
11
GND1
14
BY_CAP2
9
BY_CAP1
13
GSM850_900_OUT
10
TP3(PA_MODE)
DCS_PCS_OUT
12
TQM7M5005(5x5)
SMPY0021101
TP3(PA_MODE)
TP1(PA LEVEL)
TP2(TXON PA)
Table 4. PAM Mode Operation
MODE
GMSK
8PSK
LGE Internal Use Only
GSM850_900_IN
7
TX_EN
6
VRAMP
5
TQM7M5005H
VBATT
4
U401
BS
3
MODE_SELECT
2
DCS_PCS_IN
1
Figure 24. PAM Control Signals
Checking Points
Figure 25. Transceiver Output
MODE
LOW
HIGH
R406
10K
C433 C429 C436
C442
47P 100P 100P 100P
TP1(PA LEVEL)
PA_LEVEL
Ramp Burst Control
Control Amp bias
- 100 - Copyright © 2009 LG Electronics. Inc. All right reserved.
LBAND_PAM_IN
TXON_PA
PA_LEVEL
TP1(PA LEVEL)
PA_BAND
PA_MODE
HBAND_PAM_IN
TP3(PA MODE)
TXON_PA
HIGH
HIGH
Only for training and service purposes