LG GU280 Service Manual page 46

GSM PAM Circuit diagram
FL105
85090019002100
RF-800
PCN_RX2
SW101
C110 33p
PCN_RX1
2
G2
ANT TP1 RF ANT
G1
PCS_RX2
PCS_RX1
L101
1
GND1
100n
8
GND2 GSM850_RX_EGSM_RX2
10
GND3 GSM850_RX_EGSM_RX1
12
GND4
13
GND5 WCDMA_850
23
GND6 WCDMA_1900
24
GND7 WCDMA_2100
TP1 GSM850_EGSM_TX
PCN_PCS_TX
L106
15n
C122
33p
ANT_SEL[0]
ANT_SEL[1]
ANT_SEL[2]
ANT_SEL[3]
Table.1
(TP4)
(TP5)
Copyright © 2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
C114 2.7n
1
2
2
L112
L113
DNI
DNI
1
C113 2.7n
1
2
C174 1n
2
1
C157 1n
1
17
2
16
19
L105 33p
18
TP3
15
C162
14
C115
0.5p
15n
21
WCDMA_1900
22
L104 8.2n
WCDMA_2100
20
1
WCDMA_LB
2
11
9
TP3
GSM_PA_BAND
LOW
HIGH
C161
9.1n
C112 6p
L103 9p
9
GSM_OUT
11
TP3 DCS_PCS_OUT
C102 1.5n
27p
L102
U101
7
C111 TQM7M5012H
GND1
DNI 12
GND2
TP3
6
NC1
10
NC2
GLNA_HB_IN_P
GLNA_HB_IN_M
TP5
PCS_IN_M
PCS_IN_P
TP5
GLNA_LB_IN_P
GLNA_LB_IN_M
+VPWR
C153 C154
15p
10u
1n
C120
MODE
GSM
DCS/PCS
2
BAND_SELECT GSM_PA_BAND
1
DCS_PCS_IN
8
GSM_IN
TP4
3
TX_EN GSM_PA_EN
C178 100p
4
VBATT
R101
5
VRAMP GSM_PA_RAMP
2.2K
C152 C121
39p 22n
TP4
- 47 -
4. TROUBLE SHOOTING
R102 C131 82p
18
C176
2.7n
3 dB
D1048 FL108
C177 100p C101 8.2p
5 1
RFOUT RFIN
7
VC
GSM_SW_MODE
L114
DNI
C103
100p
836.5MHz,25MHz
LGE Internal Use Only
TX_GSM_HB
TX_GSM_LB