LG KE520 Service Manual page 49

4. TROUBLE SHOOTING
4.1.2.3 Front End Module (LMSP43NA-504TEMP)
Pass wanted signal and External LNA matching circuit.
NC2
20
NC1
19
GND5
18
GND4
16
GND3
13
GND2
12
GND1
9
VC2
10
VC1
14
LMSP43NA-504TEMP
FL400
C421
33p
LGE Internal Use Only
FL400
GSM850_900TX
17
GSM1800_1900TX
15
GSM1900RX2
8
GSM1900RX1
7
GSM1800RX2
6
GSM1800RX1
5
GSM900RX2
4
GSM900RX1
3
GSM850RX2
2
GSM850RX1
1
FL400
<Fig.3> FEM & LNA Matching Circuit Diagram
- 50 -
2.7nH
C403
L400
0.5p
C411 2.7nH
C412 3.3nH
L401
0.5p
C414 3.3nH
C415 100p
L403
10nH
C417 100p
10p
C418
L404
12nH
10p
C422
Matching circuit
Copyright © 2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes
C408
22p
A1
PCSLNAI
B1
PCSLNAIB
C2
PCSDCSGND
C1
DCSLNAI
D1
DCSLNAIB
D2
DCSG90GND
E1
G90LNAI
F1
G90LNAIB
E2
G90G85GND
G1
G85LNAI
H1
G85LNAIB
F2
G85GND
G2
GNDLNA_TX1
H2
TXON
E3