Edge/Gprs/Gsm Rf Block - LG TracFone LG840G Service Manual

WCDMA
WCDMA_850
FL102
B8553
L136 2.7n
6 1
WCDMA_850 ANT RX1
8
RX2
L137 3
C131 TX
12n
DNI 2
GND1
4 9
GND2 GND5
5 7
GND3 GND4
WCDMA 1900
FL105 LS36A
1
C150 RX1
6 8
WCDMA_1900 ANT RX2
100p
3
TX
2
C155
L142
GND1
4 7
DNI
DNI GND2 GND4
5 9
GND3 GND6

3.3 EDGE/GPRS/GSM RF block

TThe EDGE/GPRS/GSM transceiver use a digital interface that is shared between receive and transmit data.
The receive interface is based on I and Q data and the transmitter interface is based on envelop and frequency data.
The quad band EDGE/GSM/GPRS transceiver has the following general features:
Power class
GMSK low bands: Class 4 (33 dBm)
GMSK high bands: Class 1 (30 dBm)
8PSK low bands: Class E2 (27 dBm)
8PSK high bands: Class E2 (26 dBm)
Multi slot class 12 (LG840G: Multi slot class 10)
Dual Transfer Mode (DTM) class 9 (3+2=5)
Zero-IF receiver
- Polar modulation transmitter
LGE Internal Use Only
C168
W850/GSM850_RX_P
33p
C137
L117
0.5p
10n
C169
W850/GSM850_RX_M
C162 6.8p
33p
L167
C133
8.2n
DNI
L152 1.2n
W1900_RX_P
L114
C174
2p
12n
L151 1.2n
W1900_RX_M
C164 8.2p
L156 C165
15n 1.2p
Figure 3.2.3.2 WCDMA PAM schematic
- 23 -
3. TECHNICAL BRIEF
+VPWR
1608
C128
C129 C130
10u
100n 82p
C134 5.6p
L139
DNI
14 1
RFOUT_LB RFIN_LB
13 2
GND4 VMODE0
PA_R0
12 3
VCC2 U102 VMODE1 PA_R1
11 4
GND2 VCC1
10 5
RFOUT_HB VEN_LB WCDMA_PA_ON2
9 6
GND1 VEN_HB
WCDMA_PA_ON1 L155
8 7
CPL_OUT RFIN_HB
15
GND5
L163
EAN62246301
SKY77196
12n
about 6dB
R111
PWR_DET
36
R113 R112
150 150
Copyright © 2012 LG Electronics. Inc. All right reserved.
Only for training and service purposes
836.5MHz
FL103 B9425
R136 12
4 1
W850_TX_OUT
OUT IN
G3 G2 G1
5 3 2
R121
C119
L118
DNI
8.2p
100
FL104 B9459
3.6n
R122 12
4 1
OUT IN W1900_TX_OUT
G3 G2 G1
5 3 2
R143
L141
L123
DNI
<PA_ENABLE Signal>
DNI
100
W1900 : WCDMA_PA_ON1
W850 : WCDMA_PA_ON2