Checking Rf Tx Level - LG U990 Service Manual

4.6.2 Checking RF Tx Level

ANT100 ANT101 ANT102 L100
0
C102 C104
1.2p
12nH
ANT_SEL0
ANT_SEL1
ANT_SEL2
C113
47p
C114
47p
TP1
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Only for training and service purposes
KMS-518
SW100
L101
C101 120p
4.7nH
FL100
PQ
5
VC1
4
VC2
3
VC3
1
GND1
C115
2
GND2
47p
9
GND3
11
GND4
12
GND5
14
GND6
15
GND7
17
GND8
18
GND9
25
PGND1
26
PGND2
LSHS-M090UH
TP3
Schematic of the GSM Tx Block
TP2
TP3
Test Point of GSM Tx Block
4. TROUBLE SHOOTING
TP1
L102
NA
10
ANT
6
VDD
7
NC
8
UMTS_TX_RX
13
DCS_PCS_TX
16
EGSM_TX
19
DCS_RX2
20
DCS_RX1
21
PCS_RX2
22
C136 8p
PCS_RX1
23
EGSM_RX2
24
EGSM_RX1
L112
15nH
C146 10p
C142
0.75p
- 107 -
TP2
14
GND6 DCS_PCS_IN
13
GND5
12
VCC
U101
11 TQM7M5003
GND4
10
GND3
C138
9
GSM_OUT
NA
8
GND2
L113
4.7nH
PQ
LGE Internal Use Only
1
2
BS
3
TX_EN
4
VBATT
5
GND1
6
VRAMP
7
GSM_IN