Datasheet CX74002 Datasheet (CONEX)

wireless communications products

Distinguishing Features

• Best-in-class current consumption

• Tri-mode, dual-band functionality

• I/Q to RF integration

• Image-reject mixer

• Three battery-cell operation (2.7V < VCC < 3.6V)

• Split-band PCS drivers to improve Rx Band
noise performance

• Tx power control with 90dB dynamic range

• Variable-gain RF block to meet in-band signal­to-noise ratio (SNR)

• 6mm x 6mm land grid array (LGA)
chipscale package

Silicon Germanium CDMA

Transmit/Dual PLL RFlC

Conexant Delivers RF Chipsets
for 2G and 3G CDMA Applications

The CX74002 device offers the highest level of integration a tri­mode, dual-band CDMA transmit RFIC. The device is designed to
meet the needs of both 2G and 3G CDMA systems. Specifically
targeting the cdmaOne, cdma2000, and AMPS markets in the U.S.
and Korean cellular, Japan cellular, Korean PCS and U.S. PCS bands.
The CX74002 is also designed to be suitable for wideband CDMA
(WCDMA) applications in the IMT-2000 band. The device is built
using Conexant’s advanced silicon germanium (SiGe) bipolar
complementary metal oxide semiconductor (BiCMOS) process
technology. This process results in best-in-class current consumption
performance, hence increasing cellular phone talk time.

The CX74002 is a highly integrated super-heterodyne transmitter
(Tx) that incorporates all the active functional blocks up to the antenna:
an In-phase and Quadrature (I/Q) modulator that accepts the analog
I and Q outputs from the baseband analog processor and converts
them to intermediate frequency (IF) signals; a voltage controlled
oscillator (VCO) and very high-frequency (VHF) synthesizer to generate
the local oscillator (LO) signal for the quadrature demodulators for the
cellular and PCS bands; a UHF synthesizer to control the UHF oscilla­tor; and a variable gain amplifier (VGA), which is required in CDMA
systems to provide linear variable output power at the antenna.

The output of the VGA is fed to the image reject mixer. The output
of the image reject mixer is fed directly to the PA pre-driver without
the need for external SAW filters, resulting in a reduction of overall
cellular phone bill-of-material cost.

CX74002

features and specifications

www.conexant.com

Further Information

[e-mail]
[phone] (North America)
[phone] (International)
Order # 101066A
00-0880
Wireless Communications
Printed in USA

World Headquarters

Conexant Systems, Inc.
4311 Jamboree Road
Newport Beach, CA
92660-3007
Phone: [phone]
Fax 1: [phone]
Fax 2: [phone]

Americas

U.S. Northwest – Santa Clara

Phone: [phone]
Fax: [phone]

U.S. Southwest – Los Angeles

Phone: [phone]
Fax: [phone]

U.S. Southwest – Newport Beach

Phone: [phone]
Fax: [phone]

U.S. San Diego

Phone: [phone]
Fax: [phone]

U.S. North Central – Illinois

Phone: [phone]
Fax: [phone]

U.S. South Central/Mexico
– Texas

Phone: [phone]
Fax: [phone]

U.S. Northeast – Massachusetts

Phone: [phone]
Fax: [phone]

U.S. Carolinas – North Carolina

Phone: [phone]
Fax: [phone]

U.S. Southeast/South America
– Florida

Phone: [phone]
Fax: [phone]

U.S. Mid-Atlantic – Pennsylvania

Phone: [phone]
Fax: [phone]

Canada – Ontario

Phone: [phone]
Fax: [phone]

Eur

ope

Europe Central – Germany

Phone: [phone]
Fax: [phone]

Europe North – England

Phone: [phone]
Fax: [phone]

Europe – Israel/Greece

Phone: [phone]
Fax: [phone]

Europe South – France

Phone: [phone]
Fax: [phone]

Europe Mediterranean – Italy

Phone: [phone]
Fax: [phone]

Europe – Sweden

Phone: [phone]
Fax: [phone]

Europe – Finland

Phone: [phone]
Fax: [phone]

Asia Pacific

Taiwan

Phone: [phone]
Fax: [phone]

Australia

Phone: [phone]
Fax: [phone]

China – Central

Phone: [phone]
Fax: [phone]

China – South

Phone: [phone]
Fax: [phone]

China – South (Satellite)

Phone: [phone]
Fax: [phone]

China – North

Phone: [phone]
Fax: [phone]

India

Phone: [phone]
Fax: [phone]

Korea

Phone: [phone]
Fax: [phone]

Korea (Satellite)

Phone: [phone]
Fax: [phone]

Singapore

Phone: [phone]
Fax: [phone]

Japan

Phone: [phone]
Fax: [phone]

CX74002 Tx ASIC block diagram

Package dimensions — 40-pin 6mm x 6mm LGA package

Product Features

• Image reject upconverter saves two
RF surface acoustic waves (SAWs) filters
in dual-band applications

• Driver gain can be changed either by a con­tinuous signal or by a step signal through
the driver gain control signal

• 100-800 MHz oscillator (external tank)

• VCO_ON feature to increase the talk time of
the radio

• Two separate phase lock loop (PLL) synthesizers

• Dual-loop multiband operation

• Power-save mode for both standby and lower­frequency operation

• Fully programmable PLL dividers

• Selectable charge–pump currents for multi­VCO applications controlled via serial bus
interface

Applications

• cdmaOne, cdma2 000 and AMPS modes in the
following bands:

– U.S. cellular
– Japan cellular
– U.S. PC S
– Korea PCS

• WCDMA in the IMT-2000 band

Conexant and the Conexant symbol are trademarks of Conexant Systems, Inc.

The CX74002, along with Conexant’s CX74001 receive RFIC, a Conexant
power amplifier module, and Conexant’s baseband analog processor forms
a complete RF subsystem that interfaces with the most common cdma
baseband devices.