LG KP235 Service Manual page 76

7. CIRCUIT DIAGRAM
1 2
OUT500 OUT501
A
R503
0
L601
4.7nH
C608
3.9p
R507
NA
SW500
RF500
B
L501
NA
C517
22p
L502
NA
11
C
MODE VLOGIC TX_EN
L
GSM 900 RX H
H L
D DCS1800 RX
H H
GSM 900 TX
H H
DCS1800 TX
RF_TEMP
E
1 2
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Only for training and service purposes
3 4 5
R500 100ohm
R501 100ohm
R502 68
R504 100ohm
C500 C501 C502 C503
39p DNI 27p 27p
VBAT
C510
33u
6 1
DCS_RX VBATT
7 20
GSM_RX U501 GND9
8 19
GND1 DCS_IN
9 18
GND2 NC
SKY77518
10 17
GND3 GSM_IN
16
ANT GND8
C521 56p
FL500
B9308
1 9
I1 O1_1
C522 56p
8
O1_2
7
O2_1
C523 3p
4 6
I2 O2_2
2 3 5 10
C531 3p
BS
PART_NO SFSB0001401
L
H
IN CASE OF GSM900/DCS1800
CHANGE THIS DUAL SAW FILTER
L
TO PART_NO SFSB0001401
H
R517
22K
PT500
10K
3 4 5
6 7
PA_BAND
PA_EN
TX_RAMP
ANT_SW
4dB
C504
R508
24
R509 R510 33p
220 220
C505
R512
30 10p
R511 R513
QP
180 180
5dB
C509
NA
QN
2V75_VVCXO
X500
3 4
2 1
C519
0.1u
26MHz
TSX-3225_26MHZ
C520
0.1u
RX1900B
25
RX1900 VLDO2
26 16
RX1800B VLDO1
U502
27 15
RX1800 VBAT
28 14
RX900B AD6548 VDD
L503 29 13
RX900 EUSY0280101 VCC_TXVCO
6.8nH 30 12
RX850B TXOP_HI
31 11
RX850 TXOP_LO
32 10
VLDO3
9
GND
33
C527
0.1u
L504
18nH
C532 C533
27p 39p
IP
C537
NA
IN
- 87 -
8 9 10
Close to BT Module
2V75_VVCXO
R514
26MHz_BT
L500
C506
0
NA
NA
C507 C508
2.2u 39p
5
VCC
C511 1000p 2 4
26M
GND
R515
3
AFC C516
1K
NA
C518
R516 1M
0.1u
U500
MC74VHC1G04DFT2G
2V8_VMEM VBAT
C524 C525 C526
0.1u 0.1u 0.1u
C528 C529 C530
27p 0.1u 220n
S_EN
S_CLK
S_DATA
C534 C535 C536
27p 27p 27p
LGE Internal Use Only
A
B
C
D