LG CU405 Service Manual page 75

4. TROUBLE SHOOTING
4.4.4 Checking RF Rx Level
ANT100
SW100
L90
6.8p
KMS-507
VREG_RF_2.85V
TP1
ANT_SEL0
ANT_SEL1
ANT_SEL2
ANT_SEL3
TP4'
L135
VREG_W
L142
2.7nH
LGE Internal Use Only
C80 56p
G2
ANT RF
G1
15nH L106
C86 C87
0.1u 33p
1K R100
1K R101
1K R102
1K R103
WCDMA
C142
82p
TP3
WCDMA_850 ANT
GND1
GND2
GND3
FL105 L133
2 3
15nH
C163 C164 4p
G1 O1
1
IN
33p
G2 O2
5 4
C167 4p
L139
FL106
C181 10p
C182
2 3
C183
G1 O1
1 1.8p
IN
82p
G2 O2
5 4
C189
1.8p
C190 10p
TP4
14 1
VC1 GSM1800RX1
13 2
VC2 GSM1800RX2
12 3
VC3 GSM1900RX1
11 4
VC4 GSM1900RX2
5
GSM900RX1
10 6
VDD GSM900RX2
7
GSM850RX1
9 8
GND1 GSM850RX2
18
GND2
20 15
GND3 U100 UMTS1
21 16
GND4 UMTS2
23
GND5
24 22
GND6 GSM1800_1900TX
26 25
GND7 GSM850_900TX
27
GND8
28 17
GND9 NC
LMSP4LMA-573TEMP
WCDMA_1900
FL101
C135 33p
RX TX
ACMD-7402-TR1G
L125
RX_WCDMA_1900
5.6nH
TP3'
C150
56p
FL104
TX
L129
C156
RX RX_WCDMA_850
39p
15nH
GND6
GND5
GND4
LM56C
1.2nH
RX_WCDMA_850
15nH
L134
RX_WCDMA_1900
15nH
L137
1.2nH
L141
39nH
SSBDT_RFR
L143
39nH
VREG_MSMP_2.6V
Vbias'
Copyright © 2007 LG Electronics. Inc. All right reserved.
- 76 -
TP2'
L109
C88 56p
WCDMA_850
1.8nH
L112
L111
WCDMA_1900
56p
1.5nH
TP2
14
LB_LNA_IN
10
LB_LNA_OUT
5
LB_INP
4
LB_INM
15
HB_LNA_IN
9
HB_LNA_OUT
7
HB_INP
6
HB_INM
100p
32
GPS_PLNA_IN
35
C176
GPS_PLNA_OUT GPS_CP_OUT
UMTS_CP_OUT
37
GPS_INP
38
U107
GPS_INM
R132 11.8K (1%)
2
R_BIAS
(1%)
R133 5.62K
13
R_BIAS_UMTS
33
Vbias
R_BIAS_GPS
23
SSBI
34
BLANK
24
GND
49
GND_SLUG
R137
22
VDDM1
25
51
VDDM2
RFR6275
Only for training and service purposes
17
RX_QP
18
RX_QM
19
RX_IP
20
RX_IM
27
GRX_QP
28
GRX_QM
29
GRX_IP
30
GRX_IM
45
TCXO
41
47
12
NC1
43
NC2
44
NC3
1
VDDA1
3
VDDA2
8
VDDA3
11
VDDA4
16
VDDA5
21
VDDA6
26
VDDA7
31
VDDA8
36
VDDA9
39
VDDA10
40
VDDA11
42
VDDA12
46
VDDA13
48
VDDA14