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4. TROUBLE SHOOTING
CONTROL LOGIC
LGE Internal Use Only
Copyright © 2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes
Logic Table of the Antenna Switch
Schematic of the Antenna Switch Block
Mode
Vc1
Vc2
Vc3
Vc4
Vdd
GSM850/900 Tx
1.8-3.0V
1.8-3.0V
0-0.2V
0-0.2V
2.4-3.0V
GSM1800/GSM1900 Tx
1.8-3.0V
0-0.2V
0-0.2V
0-0.2V
2.4-3.0V
GSM850 Rx
0-0.2V
0-0.2V
0-0.2V
0-0.2V
2.4-3.0V
GSM900 Rx
0-0.2V
0-0.2V
1.8-3.0V
0-0.2V
2.4-3.0V
GSM1800 Rx
0-0.2V
1.8-3.0V
1.8-3.0V
0-0.2V
2.4-3.0V
GSM1900 Rx
0-0.2V
1.8-3.0V
0-0.2V
0-0.2V
2.4-3.0V
UMTS1
1.8-3.0V
0-0.2V
1.8-3.0V
0-0.2V
2.4-3.0V
UMTS2
1.8-3.0V
0-0.2V
1.8-3.0V
1.8-3.0V
2.4-3.0V
Idle
0-0.2V
0-0.2V
0-0.2V
0-0.2V
0-0.2V
C88
56p
0.1u
C86
0.5p
C98
R102
1K
C87
33p
R100
1K
15nH
L106
C92
NA
1K
R103
R101
1K
14
13
VC2
VC3
12
11
VC4
VDD
10
26
GND8
27
28
GND9
1
GSM1800RX1
GSM1800RX2
2
22
GSM1800_1900TX
3
GSM1900RX1
GSM1900RX2
4
GSM850RX1
7
8
GSM850RX2
GSM850_900TX
25
5
GSM900RX1
GSM900RX2
6
NC
17
UMTS1
15
16
UMTS2
VC1
U100
LMSP4LMA-573TEMP
ANT
19
9
GND1
GND2
18
GND3
20
GND4
21
23
GND5
24
GND6
GND7
56p
L111
ANT_SEL2
ANT_SEL3
ANT_SEL0
ANT_SEL1
VREG_RF_2.85V
TP1
Summary of Contents for CU405
Page 1: ...Date May 2007 Issue 1 0 Service Manual Model CU405 Service Manual CU405 Internal Use Only ...
Page 175: ...Note ...
Page 176: ...Note ...