Checking Front-End Module Block - LG CU720 Service Manual

4.6 Checking Front-End Module Block

ANT_SEL0
ANT_SEL1
ANT_SEL2
ANT_SEL3
VREG_RF_SMPS
[Fig4.6.1] Schematic of the Front-End Module Block
[Fig4.6.2] Test Point of the Front-End Module Block
Copyright © 2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes
C108
120p C110 C111 C112
120p 120p 120p
TP1
C120 C121
0.1u 33p
TP1
- 85 -
4. TROUBLE SHOOTING
FL101
LMSP4LMA-573TEMP
14 1
VC1 GSM1800RX1
13 2
VC2 GSM1800RX2
12 3
VC3 GSM1900RX1
11 4
VC4 GSM1900RX2
5
GSM900RX1
10 6
VDD GSM900RX2
7
GSM850RX1
9 8
GND1 GSM850RX2
18
GND2
20 15
GND3 UMTS1
21 16
GND4 UMTS2
23
GND5
24 22
GND6 GSM1800_1900TX
26 25
GND7 GSM850_900TX
27
GND8
28 17
GND9 NC
ANT_SEL3
ANT_SEL2
ANT_SEL1
ANT_SEL0
LGE Internal Use Only