User Guide

PAMS
Technical Documentation
NME–3
Technical Information
Page 41
Issue 1 10/99
Table 19. List of supply voltages (continued)
Current consumptionLoadName of supplyRegulator in CCONT
VR 4 VVCO UHFVCO
VHFVCO
CRFU 1a
10 mA
5 mA
7 mA
VR 5 VRX2 Plussa RX path max. 32 mA
VR 6 VCOBBA COBBA analog circuits BB responsibility
VR 7 VTX PLUSSA and CRFU 1a
TX path
72 mA
V5V VCP Charge pumps in
PLUSSA
4 mA
VREF VREF Reference voltage for
CRFU1a and PLUSSA
––– V8PA TX buffer
LO buffer
Bias of detector diode
OPAMPs for PA control
15 mA
15 mA
10 mA
––– VPA Supply voltage PA max. 4 A
Functional Description
The RF block diagram shows a conventional dual conversion receiver and
the transmitter uses a single upconversion mixer. The architecture
contains two RF ASICs, PLUSSA and CRFU1a.
CRFU1a is a BiCMOS circuit containing the LNA, RX mixer and TX mixer
stages for the handportable GSM phones. However, in order to fulfill the
specifications for the CD949 project a discrete LNA and a discrete RX
mixer were employed.
PLUSSA is also a BiCMOS circuit which contains the IQ modulator for the
transmitter and the receiver stages between the channel filter and
COBBA. It also contains the PLLs for both the VHF and UHF synthesizers.
The Power amplifier is a MMIC ( monolithic microwave integrated circuit )
supplied by Hitachi. It has three amplifier stages including input and
interstage matching.
Using the high integrated engine of DCT3 as much as possible reduces
the component count. With this approach we want to fulfill the high
demands for the reliability demands of the automotive industry.