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4. TROUBLE SHOOTING
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4.6.5 Checking RF Rx Block
GSM.RX
PCS.RX
DCS.RX
Test Point (RF Rx Level)
925-960 MHz
1805-1880 MHz
(1%)
1930-1990 MHz
(PPS)
L1018
3.6nH
VDDA6
VDDA7
26
27
VDDA8
31
VDDA9
43
VDD_M
TX_VCO_FB
42
VDDA10
36
39
VDDA11
VDDA12
41
VDDA13
47
RF_ON_TX_ON
RX_VCO_IN
32
R_BIAS
33
SBCK
44
SBDT
45
46
SBST
40
TX_MOD_CP
CP2
30
CP_HOLD2
29
28
FAQ2
34
GSM1800_INN
GSM1800_INP
35
24
GSM1900_INN
GSM1900_INP
25
38
GSM900_INN
GSM900_INP
37
1000p
C1085
R1036
L1033
3.3nH
9.1nH
L1015
C1094
33p
33p
C1093
L1016
7.5nH
3.3nH
L1032
C1084
22n
82
R1037
0
R1038
11K
R1039
0.1u
C1089
33p
C1090
10nH
L1028
120p
C1083
1000p
C1087
C1092
0.1u
L1017
7.5nH
L1014
9.1nH
L1030
L1029
5.1nH
5.1nH
C1086
1000p
C1079
82p
3.6nH
L1019
C1088
1000p
47nH
L1020
L1027
10nH
VREG_RFRX_0_2.85V
VREG_RFTX_2.85V
Schematic of GSM/DCS/PCS Rx Block
Summary of Contents for U880
Page 1: ...Date November 2005 Issue 1 0 Service Manual Model U880 Service Manual U880 ...
Page 20: ...3 TECHNICAL BRIEF 21 ...
Page 32: ...3 TECHNICAL BRIEF 33 Figure 3 5 6 1 GSM PA functional block diagram ...
Page 35: ...3 TECHNICAL BRIEF 36 Figure 3 5 10 1 Bluetooth system architecture ...
Page 50: ...3 TECHNICAL BRIEF 51 Figure 3 10 3 2 1 PM6650 Functional Block Diagram ...
Page 114: ...4 TROUBLE SHOOTING 115 Loud Speaker U502 U503 Amp ...
Page 118: ...4 TROUBLE SHOOTING 119 C200 C201 for MIC serial capacitor ...
Page 121: ...4 TROUBLE SHOOTING 122 Q404 Q403 Q402 VBATT GND ...
Page 128: ...5 DOWNLOAD 129 5 Choose a Module Image file after clicking on the Browse button ...
Page 143: ...6 BLOCK DIAGRAM 144 6 3 Interface Diagram U880 Interface Diagram ...
Page 145: ... 146 ...
Page 154: ... 155 8 PCB LAYOUT ...
Page 155: ... 156 8 PCB LAYOUT ...
Page 156: ... 157 8 PCB LAYOUT ...
Page 157: ... 158 8 PCB LAYOUT ...
Page 158: ... 159 8 PCB LAYOUT ...
Page 159: ... 160 8 PCB LAYOUT ...
Page 166: ...9 CALIBRATION 167 Click START button U880 U880_ver1 1 U880 U880 Click U880 ...
Page 167: ... 168 ...
Page 168: ... 169 ...
Page 170: ... 171 ...
Page 171: ... 172 ...
Page 196: ...Note ...
Page 197: ...Note ...