CONEX CX74001 Datasheet

wireless communications products

Distinguishing Features

• Tri-mode, dual-band functionality

• RF to I/Q integration

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

• PCS bypass LNA with NF 1.9 dB typical

• Three-step cellular LNA with NF 1.8 dB
typical at maximum gain

• Dual 200 to 600 MHz 2nd IF Oscillators

• 7mm x 7mm land grid array (LGA)
chipscale package

CDMA Receive RFlC

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

The CX74001 offers the highest level of integration in a tri-mode, dual­band receiver (Rx) 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 CX74001 is also
designed to be suitable for wideband CDMA (WCDMA) applications
in the IMT-2000 band. Programmable linearity is included in the RF
front end to optimize power consumption at various input levels. A
three-step cellular LNA, bypass PCS LNA, and a seperate enable for
the internal VCO increases system performance and standby times.

The device is a highly integrated super-heterodyne receiver. It incor­porates all the components required to implement the receiver front
end and the In-phase and Quadrature (I/Q) demodulator stages,
except for the filter blocks. It has two internal LNAs — one for the
cellular band and another for the PCS band.

The device also has separate mixers for the AMPS, CDMA and PCS
bands. The AMPS mixer has differential outputs that are combined
externally as a single-ended output for the intermediate frequency (IF)
surface acoustic wave (SAW) filter. The cellular and PCS mixers have
balanced outputs for the CDMA IF SAW filters. The mixers are fol­lowed byan IFvariable gain amplifier (VGA) and an I/Q demodulator.

The outputs from the filters are combined through separate buffers
at the input of the VGA. The buffers are enabled 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.

CX74001

features and specifications

The CX74001, along with Conexant’s CX74002 transmit 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.

www.conexant.com

Further Information

[e-mail]
[phone] (North America)
[phone] (International)
Order # 101065A
00-0889
Wireless Communications
Printed in USA

World Headquarters

Conexant Systems, Inc.
4311 Jamboree Road
Newport Beach, CA
92660-3007
Phone: [phone]
Fax 1: (949) 483- 4078
Fax 2: (949) 483- 4391

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: (727) 799 - 8406
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: (86 ) 755-5183024

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]

CX74001 Rx ASIC block diagram

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

CX74001 48-pin 7mm x 7mm LGA package

Product Features

• Two on-chip oscillators, one for cellular and
one for PCS bands

• 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

• Three-step gain LNA designed to meet
intermodulation distortion specifications for
CDMA applications

• Three independent mixers, one for the PCS
band and two for the cellular band, designed
to operate with very low LO power of -10dBm

Applications

• 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