• Tri-mode, dual-band functionality
• Superior gain and phase balance in the
I/Q demodulator (0.2 dB + 2º typical)
• 90 dB of dynamic range in the variable
gain amplifier
• Three battery-cell operation
(2.7V < VCC < 3.6V)
• IF inputs and I/Q outputs
• On-chip 100 to 640 MHz oscillators
• Low-power operation: <20 mA
• 5mm x5mm land grid array (LGA)
chipscale package
wireless communications products
VGA+l/Q
Demodulator RFlC
CX74005
Conexant Delivers RF Chipsets
for 2G and 3G CDMA Applications
The CX74005 RFIC is a variable gain amplifier (VGA) and In-phase
and Quadrature (I/Q) modulator, intended for use in code division
multiple access (CDMA) portable phones in the cellular and
Personal Communications System (PCS) bands. As a dual-mode
IC, it can be used in CDMA mode or advanced mobile phone
system (AMPS) mode. In addition, this device can be used for
wideband CDMA (WCDMA) applications in the IMT-2000 band.
The intermediate frequencies (IF) are combined through separate
buffers at the input of the VGA, depending on the selected mode.
The VGA has a gain control range greater than 90 dB. The device
has two very high-frequency (VHF) oscillators that operate with
external tank circuits. They provide signals to the local oscillator
(LO) for the I/Q demodulator in the cellular and PCS bands.
The I/Q demodulator provides a superior gain and phase balance
of typically less than 0.2 dB gain and 2º phase imbalances.
Employing silicon bipolar technology, the CX74005 is designed
for high performance and a high level of integration.
The CX74005, along with Conexant’s CX74002 Transmit RFIC,
CX74004 LNA/mixer RFIC, a Conexant power amplifier module and
Conexant’s baseband processor forms a complete RF subsystem
that interfaces with the most common cdma baseband devices.
Distinguishing Features
www.conexant.com
Further Information
literature@conexant.com
(800) 854-8099 (North America)
(949) 483-6996 (International)
Order # 101068A
00-0882
Wireless Communications
Printed in USA
World Headquarters
Conexant Systems, Inc.
4311 Jamboree Road
Newport Beach, CA
92660-3007
Phone: (949) 483-4600
Fax 1: (949) 483-4078
Fax 2: (949) 483-4391
Americas
U.S. Northwest - Santa Clara
Phone: (408) 249-9696
Fax: (408) 249-7113
U.S. Southwest - Los Angeles
Phone: (805) 376-0559
Fax: (805) 376-8180
U.S. Southwest - Newport Beach
Phone: (949) 483-9119
Fax: (949) 483-9090
U.S. San Diego
Phone: (858) 713-4730
Fax: (858) 713-4008
U.S. North Central - Illinois
Phone: (630) 773-3454
Fax: (630) 773-3907
U.S. South Central/Mexico
- Texas
Phone: (972) 871-1920
Fax: (972) 871-8910
U.S. Northeast - Massachusetts
Phone: (978) 367-3200
Fax: (978) 256-6868
U.S. Carolinas - North Carolina
Phone: (919) 858-9110
Fax: (919) 858-8669
U.S. Southeast/South America
- Florida
Phone: (727) 799-8406
Fax: (727) 799-8306
U.S. Mid-Atlantic - Pennsylvania
Phone: (215) 244-6784
Fax: (215) 244-9292
Canada - Ontario
Phone: (613) 271-2358
Fax: (613) 271-2359
Europe
Europe Central - Germany
Phone: +49 89 829-1320
Fax: +49 89 834-2734
Europe North - England
Phone: +44 1344 486444
Fax: +44 1344 486555
Europe - Israel/Greece
Phone: +972 9 9524000
Fax: +972 9 9573732
Europe South - France
Phone: +33 1 41 44 36 51
Fax: +33 1 41 44 36 90
Europe Mediterranean - Italy
Phone: +39 02 93179911
Fax: +39 02 93179913
Europe - Sweden
Phone: +46 (0) 8 5091 4319
Fax: +46 (0) 8 590 041 10
Europe - Finland
Phone: +358 (0) 9 85 666 435
Fax: +358 (0) 9 85 666 220
Asia Pacific
Taiwan
Phone: (886-2) 2-720-0282
Fax: (886-2) 2-757-6760
Australia
Phone: (61-2) 9869 4088
Fax: (61-2) 9869 4077
China - Central
Phone: 86-21- 6361-2515
Fax: 86-21-6361-2516
China - South
Phone: (852) 2 827-0181
Fax: (852) 2 827-6488
China - South (Satellite)
Phone: (86) 755-5182495
Fax: (86) 755-5183024
China - North
Phone: (86-10) 8529-9777
Fax: (86-10) 8529-9778
India
Phone: (91-11) 692-4789
Fax: (91-11) 692-4712
Korea
Phone: (82-2) 565-2880
Fax: (82-2) 565-1440
Korea (Satellite)
Phone: (82-53) 745-2880
Fax: (82-53) 745-1440
Singapore
Phone: (65) 737 7355
Fax: (65) 737 9077
Japan
Phone: (81-3) 5371 1520
Fax: (81-3) 5371 1501
features and specifications
Product Features
• Two on-chip oscillators, one for cellular and
one for PCS bands
• Local oscillators for I/Q demodulators are
derived by a selectable (2 or 4) frequency divider
• VGA has a minimum dynamic range of 90 db
with a control voltage range of 0.2 to 2-7 volts
• The appropriate signal path is switched
internally to the device, eliminating the
need for off-chip switching
Applications
•Tri-mode handsets
•Cellular- and PCS-band phones
•cdmaOne, cdma2000 and AMPS modes in the
following bands:
- U.S. cellular
- Japan cellular
- U.S. PCS
- Korea PCS
•WCDMA in the IMT-2000 band
Conexant and the Conexant symbol are trademarks of Conexant Systems, Inc.
Package dimensions - 32-pin 5x5mm LGA package
CX74005 Rx ASIC block diagram
