LG L240 Service Manual page 39

4. TROUBLE SHOOTING
C711
33p
C724
33p
US_EURO LB_HB
Low Low
Low Low
Low Low
Low Low
Low High
Low High
Low High
Low High
Low High
High High
High Low
Low Low
<Table.1> Power Amplifier Front End Module Logic Table
VCC_2.8V
C702 C703
33p 33p
VDETECT
C713 0.01u
28
CAP_LB1
C714 1000p 29
CAP_LB2
C716 4700p 23
CAP_HB1
C717 1000p 22
U701
CAP_HB2
MMM6027
15
TX_EN
8
TX_ANT_SW_EN
9
LB_HB
13
US_EURO
17
IPC_BCM
C722
33p
C725
33p
C733 C734
33p 33p
<Fig.3> PAFEM Circuit Diagram
TX_ANT_SW_EN TX_EN
High High
High High
High High
High High
High High
High High
High High
High High
Low Low
Low Low
Low Low
Low Low
- 40 -
VBAT
C704
10u
C707 C708 C709 C710
15p 39p 15p 1u
6
ANT
1
RX_PCS_OUT
2
RX_DCS_OUT
3
RX_EGSM_OUT
4
RX_GSM850_OUT
26
TX_LB_IN
25
TX_HB_IN
32
C721
NC3 C720
33
33p
NC2 15p
34
NC1
R703 R706
R704
R705
NA NA
0
0
R707 R708
NA NA
IPC_BCM MODE
High TX_GMSK
Low TX_EDGE
High TX_GMSK
Low TX_EDGE
High TX_GMSK
Low TX_EDGE
High TX_GMSK
Low TX_EDGE
X
X
X
X
BAND
GSM850
GSM850
EGSM900
EGSM900
DCS1800
DCS1800
PCS1900
PCS1900
Pin 4 RX4
Pin 3 RX3
Pin 2 RX2
Pin 1 RX1