Checking Ant. Sw Module Block - LG U880 Service Manual

4.4 Checking Ant. SW Module Block

ANT_SEL2
ANT_SEL1
ANT_SEL0
VREG_RFRX_0_2. 85V
VREG_RFRX_0_2.85V
Mode
EGSM TX
EGSM RX
DCS/PCS TX
DCS RX
PCS RX
UMTS
Antenna Switch Block(Bottom)
ANT1000
ANT1001
SW1002
C1230
G2
ANT RF
G1
15p
KMS-512
C1112
L1035 L1034
0.5p
4.7nH 15nH
L1031 7.5nH
C1108
0.1u
ANT_SEL0
ANT_SEL1
ANT_SEL2
Schematic of the Antenna Switch Block
ANT_SEL0
LOW
HIGH
LOW
LOW
HIGH
LOW
Logic Table of the Antenna Switch
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4. TROUBLE SHOOTING
C1111 33p
FXL4T245BQX U1008
1 9 2
VCCA _OE CTRL1
14 4
VCCB
CTRL2
6 11
T__R CTRL3
7 20
GND1
CTRL4
8
GND2
15
BGND
13 2 8
B0 A0 UMTS
12 3
B1 A1
11 4
B2 A2
10 5
B3 A3
ANT_SEL1
LOW
LOW
HIGH
LOW
LOW
LOW
M054E
M054E
U1006
12
RX_DCS1
13
RX_DCS2
14
RX_PCS1
15
RX_PCS2
16
RX_EGSM1
17
RX_EGSM2
3
TX_DCSPCS
1
TX_EGSM
ANT_SEL2
LOW
LOW
LOW
LOW
LOW
HIGH