Preliminary
RF2721
QUADRATURE DEMODULATOR
2
Typical Applications
• UHF Digital and Analog Receivers
• Digital Communication Systems
• Commercial and Consumer Systems
• Portable Battery-Powered Equipment
• Spread-Spectrum Communication Systems
• General Purpose Frequency Conversion
Product Description
The RF2721 is a monolithic integrated quadrature
demodulator intended for use in digital mobile radio
receivers. In this application it is used to recover the in-
phase and quadrature baseband signals from the ampli-
fied and filtered IF. The RF2721 is intended for IF sys-
tems where the IF frequency ranges from 100kHz to
500MHz, and the LO frequency is two times the IF. The
IC contains all of the required components to implement
the demodulation function of the receiver and contains a
digital divider type 90° phase shifter, two double-balanced
mixers, and baseband amplifiers designed to interface
with analog to digital converters. The output DC offset
may be slaved to the reference of the ADCs to maintain
DC accuracy.
Optimum Technology Matching® Applied
0.156
0.148
.018
.014
0.010
0.004
0.347
0.339
0.050
0.252
0.236
0.059
0.057
7
QUADRATURE
DEMODULATORS
8° MAX
0° MIN
0.0500
0.0164
0.010
0.007
Package Style: SOIC-14
ü
Si Bi-CMOS
IF1+ 1
GND 2
OSCB 3
OSCE 4
GND 5
Si BJT
GaAs HBT
SiGe HBT
GaAs MESFET
Si CMOS
Features
• 5V Power Supply
• On-Chip Active Device for Oscillator
14 IF IN-
13 VCC
12 PD
11 GND
10 I OUT
5 kΩ
9 REF IN
5 kΩ
8 Q OUT
• ADC Compatible Outputs
• Low LO Power Requirement
• Digitally Controlled Power Down Mode
• 100kHz to 500MHz IF Operation
POWER
CONTROL
LO2- 6
LO2+ 7
QUAD
DIV.
BY 2
Ordering Information
RF2721
RF2721 PCBA
Quadrature Demodulator
Fully Assembled Evaluation Board
Functional Block Diagram
RF Micro Devices, Inc.
7628 Thorndike Road
Greensboro, NC 27409, USA
Tel (336) 664 1233
Fax (336) 664 0454
http://www.rfmd.com
Rev A2 010509
2-27
RFMD [ RF MICRO DEVICES ]
