LG KU950 - Checking Rf Rx Block

4. TROUBLE SHOOTING
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4.6.5 Checking RF Rx Block
Test Point (RF Rx Level)
Schematic of GSM/DCS/PCS Rx Block
(1%)
(PPS)
1805-1880 MHz
925-960 MHz
(2012)
1930-1990 MHz
(2012)
EUSY0203802
(PPS)
VREG_SYNTH_2.85V
680p
C110
R109
82
C127
8200p
33p
C108
1.8nHL109
C125
120p
L114 4.7nH
4.7K
R102
8.2nHL115
6.8n
C111
4.3K
R103
R106 11K
18nH
L113
L108
4.7nHL112
1.2p
L116
18nH
C115
VDDA6
23 26
VDDA7 VDDA8
27
VDDA9
31
_
M
V
0.01u
42
TX_VCO_FB
T
S1900_OUT
T
S2100_OUT
TS800 OUT
O
NTROL
36
VDDA10
VDDA11
39
41
VDDA12
A13 A14 A15 A16
O
N_TX_ON
32
RX_VCO_IN
33
R_BIAS
K
TX_IN
19
TX_IP
18
TX_MOD_CP
40
17
TX_QN
TX QP
30
CP2
29
CP_HOLD2
20
DAC_REF
FAQ2
28
GSM1800_INN
34
35
GSM1800_INP
GSM1900_INN
24 25
GSM1900_INP
21
GSM850_INN
22
GSM850_INP
GSM900_INN
38
37
GSM900_INP
RTR6250D
U100
L106 1.8nH
L117 8.2nH
33p
C114
VREG_RFTX_2.85V
C126
1000p
CP2_OUT
RX_VCO_IN
PCS RX
DCS RX
GSM RX