General Description - LG GS290 Service Manual

3. TECHNICAL BRIEF

3.16. General Description

The RF transceiver (PMB 6272 SMARTi-PM) is an integrated single chip, quad-band transceiver for
GSM850/GSM900/GSM1800/GSM1900 designed for voice and data transfer applications. The transceiver
provides an analog I/Q baseband interface and consists of a direct conversion receiver and a quad-band polar
transmitter for GSM and EDGE with integrated PGA functionality. Further on a completely integrated
SD-synthesizer with HSCSD and GPRS/EDGE capability, a digitally controlled reference oscillator with three
outputs, a fully integrated quad-band RF oscillator and a three wire bus interface with all necessary control
circuits complete the transceiver.
Figure 23 RF transceiver PMB6272 SMARTi-PM functional block diagram
LGE Internal Use Only - 54 - Copyright © 2010 LG Electronics. Inc. All right reserved.
Only for training and service purposes
VC1
VC2 FE2
33
VBIAS
34
VDDTX1V5
35
LBAND_PAM_IN TX1
36
HBAND_PAM_IN TX2
U500
37
R507 VDDTX2V8
38 PMB6272
VDDMIX2V8
10 39
C522
GND3
220n 40
GND4
41
VRF_1V5
VRF_2V85
C511 C518
220n 0.1u
Figure 24 RF transceiver PMB6272 SMARTi-PM schematic
Copyright © 2010 LG Electronics. Inc. All right reserved. - 55 -
Only for training and service purposes
3. TECHNICAL BRIEF
VRF_1V5 VRF_2V85 VRF_2V85
C506 C537 C536 C535
0.1u 0.1u 0.1u 0.1u
VDDRX2V8
20
VDDRX1V5
19
VCO_RC
18
VDDVCO2V8
17
EN RF_EN
16
VDDXO2V8
C516 1n
15
FSYS1 26MHZ_MCLK
14
GND1
13
R508 C517
47n
820
X500 TSX-3225
4
3
GND2 HOT2
1 2
HOT1 GND1
26MHz
CLK26M
RF_CLK
RF_DA
QX
Q
IX
I
LGE Internal Use Only