LG KF700Q Service Manual page 126

4.17.3 Checking PAM Block
+VPWR +VPWR
C157 C157
C156 C156 15p 15p
L112 L112
NA NA
C159 C159 15p 15p C160 C160
L113 L113
6.8nH 6.8nH
Test Point Net name
TP1 GSM_PA_RAMP
TP2 GSM_PA_EN
TP3 +VPWR
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
TP3
C152 C152 C153 C153 C154 C154
15p 15p 1000p 1000p
4.7u 4.7u
1.5nH 1.5nH
U102 U102
TQM7M5012 TQM7M5012
BAND_SELECT BAND_SELECT
9
GSM_OUT GSM_OUT
DCS_PCS_IN DCS_PCS_IN
39p 39p
11 11
DCS_PCS_OUT DCS_PCS_OUT
GSM_IN GSM_IN
7
GND1 GND1 TX_EN TX_EN
12 12
GND2 GND2
VBATT VBATT
6
NC1 NC1
10 10
NC2 NC2 VRAMP VRAMP
[Fig. 4.24] Schematic of PAM Block
[Fig. 4.25] Test Point of PAM Block
Description
Power Amp Gain Control. Typically, 0.2 ~1.6V
Power Amp Enable (ON : >2.5V, OFF : <0.7V)
PAM Supply Voltage (Vcc > 3V)
- 127 -
4. TROUBLE SHOOTING
FL102 FL102
LMSM32AA-533 LMSM32AA-533
5 1
RFOUT RFOUT RFIN RFIN
7
VC VC
TP1
2
1
8
3
4
R113 R113
5
2.2K 2.2K
C164 C164
39p 39p
TX_GSM TX_GSM
R111 R111
GSM_SAW_SW_MODE GSM_SAW_SW_MODE
100ohm 100ohm
C155 C155
100p 100p
TP2
GSM_PA_BAND GSM_PA_BAND
TX_DCS_PCS TX_DCS_PCS
GSM_PA_EN GSM_PA_EN
GSM_PA_RAMP GSM_PA_RAMP
C165 C165 C166 C166
DNI DNI DNI DNI
LGE Internal Use Only