Checking Front-End Module Block - LG KB770 Service Manual

4.5 Checking Front-End Module Block

G2
G1
UFL-R-SMT10
[Fig4.5.1] Schematic of the Front-End Module Block
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
SW101
SW100
R100 0
G2
ANT
ANT
G1
C101
C104
DNI
DNI
KMS-512
TP1
VREG_RF_SMPS
C112 C113
0.1uF 33p
R107 1K
ANT_SEL0
R108 1K
ANT_SEL1
R110
ANT_SEL2
ANT_SEL3
Bottom side
[Fig4.5.2] Test Point of the Front-End Module Block
C100 56p
RF
C102
56nH
LMSP4LMA-573TEMP
14
VC1
13
VC2
12
VC3
11
VC4
L107 47nH
10
VDD
9
GND1
18
GND2
20
GND3
21
GND4
23
GND5
24
GND6
26
GND7
27
GND8
28
GND9
1K
R111 1K
- 85 -
4. TROUBLE SHOOTING
FL100
1
GSM1800RX1
2
GSM1800RX2
3
GSM1900RX1
4
GSM1900RX2
5
GSM900RX1
6
GSM900RX2
7
GSM850RX1
8
GSM850RX2
15
UMTS1
16
UMTS2
22
GSM1800_1900TX
25
GSM850_900TX
17
NC
ANT_SEL 0
ANT_SEL 1
ANT_SEL 2
ANT_SEL 3
TP1
LGE Internal Use Only