LG GT500 - RF Technical Description

- 62 -
LGE Internal Use Only Copyright © 2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
3. TECHNICAL DESCRIPTION
Figure 3-7-1. Block diagram of RF part
3.7.1. General Description
The RF platform of GT500 supports two different communication modes (WCDMA/GSM modes) including
four communication bands (WCDMA2100/WCDMA900/GSM850/900/1800/1900). The all the RF blocks can be
divided into three main parts, which are a WCDMA part, a GSM, and a RF front-end. Different from other
general solutions, the RF front-end of GT500 consists of an antenna switch and an EDGE power amplifier
module (PAM). The simplified block diagram is shown in Figure 3-7-1.
3.7. RF Technical Description
3.7.2. WCDMA Part
The W-CDMA transceiver uses differential analog in-phase and quadrature-phase interfaces, that is an
IQ-interface, both in the receiver and transmitter information path. The transceiver has the following
general features:
. Power class : Power class 3 (+24dBm) in Band I
. Power class : Power class 3 (+24dBm) in Band VIII
. Zero-IF Receiver.No IF filter needed
. Direct IQ modulation transmitter
U330
GSM/EDGE
PA + Ant Sw.
ANT
VAPC
RADCLK
RADDAT
RADSTR
VBAT
2.75 V
VRAD
1.8 V
VIO
PA
PA
GSM850/
900 Input
DCS/PCS
Input
ESD
2.75 V
VRAD
LNA
LNA
LNA
LNA
LNA
A
D
A
D
0
90
LPF
+
ChP PhD
÷
N.M
VCO
LPF ChP PhD
÷
N.M
+
0
90
+
DAC
DAC
XO
DAC
VCO
VCO
LNA
LNA
WCDMA LB
WCDMA HB
WCDMA HB
WCDMA HB
CLK
DATA
STROB E
Serial
Control
WTxQB
WTxQA
WTxIB
WTxIA
GSM/E DGE
AM
DAC
RFCtrl1
RFCtrl2
RFCtrl1
RFCtrl2
GSM/
EDGE HB
GSM/
EDGE LB
WCDMA LB
WCDMA HB
WCDMA HB
GSM/E DGE
LB
GSM/E DGE
LB
GSM/E DGE
HB
GSM/E DGE
HB
WRxIA
WRxIB
WRxQB
WRxQA
EDataA
EDataB
EDataC
EDataStr
WCDMA/GSM/GPRS/EDGE TRX
MCLK
CLKREQ
MCLKSec
XO
XOn
XOp
26MHz
X-tal
VBAT
VccWPA
VccWPA
Power
coupler
Power
coupler
VccWPA
VccWPA
RF Pow det
Det
En
Bias
DET
En
Bias
DET
En
Bias
DET
En
UL: 1920 – 1980 MHz
DL: 2110 – 2170 MHz
UL: 1749.9 – 1784.9 MHz
DL: 1844.9 – 1879.9 MHz
UL: 830 – 840 MHz
DL: 875 – 885 MHz
824 – 915 MHz
1710 – 1910 MHz
1930 – 1990 MHz
1805 – 1880 MHz
925 – 960 MHz
869 – 894 MHz
WDCDCREF
WPOW_DET _EN
FB
Switch
PWM/PFM
En
Cont rol
Logic
RFCtrl1