LG HB620 Service Manual page 120

4.17.2 Checking RF Tx Level
ANT101
ANTENNA
OUT101
2.7nH
C102
L103
1.5p
15nH
L102
ANT_SEL0
ANT_SEL1
ANT_SEL2
C112
33p
ANTENNA SWITCH MODULE LOGIC
ANT_SEL0
EGSM TX
DCS/PCS TX
UMTS2100
EGSM/PCS RX
DCS RX
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
SW101
KMS-518
TP1
C103 33p
C104
L104
0.1u
56nH
FL101
LSHS-M090UH
5 10
VC1 ANT
4
VC2
3 6
VC3 VDD
7
NC
C113 1
GND1
33p
2 8
GND2 UMTS_TX_RX
9 13
C111 GND3 DCS_PCS_TX
11 16
33p
GND4 EGSM_TX
12
GND5
14 19
GND6 DCS_RX2
15 20
GND7 DCS_RX1
17 21
GND8 PCS_RX2
18 22
GND9 PCS_RX1
25 23
PGND1 EGSM_RX2
26 24
PGND2 EGSM_RX1
ANT_SEL1 ANT_SEL2
HIGH HIGH LOW
HIGH LOW LOW
TP2
HIGH LOW HIGH
LOW LOW / HIGH LOW
LOW HIGH HIGH
TP3
[Fig. 4.16] Schematic of the GSM Tx Block
[Fig. 4.17] Test Point of GSM Tx Block
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4. TROUBLE SHOOTING
VREG_RF_SMPS
L105
DCS L106
39nH
L108
L109
PCS L110
NA
L113
L114
L115
GSM
NA
L117
R107
GSM_PA_RAMP
2.2K
C132
68p
C136
56p
C137 16
DCS_PCS_OUT U102
NA
SKY77329
9
GSM_OUT
C138
56p
C141
NA
5.6nH
L107
27nH
5.6nH
6.8nH
L111
12nH
6.8nH
27nH
L116
27nH
27nH
C126 C127
1u 33u
2
DCS_PCS_IN
7
GSM_IN
1
TX_EN
3
BS
LGE Internal Use Only