Micro Linear makes no representations or warranties with respect to the accuracy, utility, or completeness of the contents of this publication and reserves the right to make changes to specifications and product

descriptions at any time without notice. No license, express or implied, by estoppel or otherwise, to any patents or other intellectual property rights is granted by this document. The circuits contained in this

document are offered as possible applications only. Particular uses or applications may invalidate some of the specifications and/or product descriptions contained herein. The customer is urged to perform its

own engineering review before deciding on a particular application.

Micro Linear assumes no liability whatsoever, and disclaims any express or implied warranty, relating to sale and/or use of Micro Linear

products including liability or warranties relating to merchantability, fitness for a particular purpose, or infringement of any intellectual property right. Micro Linear products are not designed for use in medical,

Micro Linear has developed a single IC radio, the ML2721.

The very high level of integration

absorbs all the circuits either difficult to design or those that require production alignment. Adding

just an external RF switch makes a complete radio with a digital control interface. On receive, the

input is RF, the output is demodulated data. All the LO circuits are integrated, including the VCO

tank circuit which Micro Linear tunes in production. For transmit, the chip is digital data in and

modulated RF out. To ensure proper functionality in products, all the DC regulation and power

management functions are integrated into the ML2721. This chip can be used for 900MHz ISM

band applications, as either a 1.1Mbps to 1.6Mbps FSK radio, or a 1.1Mcps direct sequence radio.

To extend the radio range, the ML2751 integrates a 100mW PA and a 18dB gain LNA. The ML2751

PA/LNA can implement front-end solutions for many communications products using TDD/TDMA

(half duplex radios) in the 600MHz to 1 GHz range and for transmitter powers up to 100mW at 3.0V.

CORPORATE HEADQUARTERS

WESTERN UNITED STATES

Micro Linear Corporation

2092 Concourse Drive

San Jose, CA 95131

Tel: (408) 433-5200

Fax: (408) 432-1627

http//www.microlinear.com

CENTRAL UNITED STATES

Micro Linear Corporation

59 Cardinal Street

Pearl River, NY 10965

Tel: (914) 735-5848

Fax: (914) 735-5852

EASTERN UNITED STATES

Micro Linear Corporation

35 Pinehurst Avenue

Nashua, NH 03062

Tel: (603) 888-1326

Fax: (603) 888-4239

EUROPE

Micro Linear Corporation

Babraham Road

Sawston, Cambridge

CB2 4LJ, UK

Tel: 44-1223-839534

Fax: 44-1223-836761

ASIA

Micro Linear Corporation

#705 2-8-12 Mita

Minato-ku, Tokyo 108-0073

Tel/Fax: +81-3-5439-6256

ML2731

ML2751

RF PIN

DIODE

SWITCH

ANTENNA

PIN DIODE

DRIVERS

PA & DRIVER

902 - 928

MHz FILTER

Tx RF

BUFFER

LNA

IF CIRCUITS

Tx DATA

FILTER

BATTERY

WATCH

AND

OSCILLATOR

XTAL

KEYPAD

DISPLAY

MIC

SPEAKER

RINGER

FILTER

ALIGN

PLL

CONTROL

LOGIC

LOOP

FILTER

VTUNE

QUADRATURE

DIVIDED BY 2

BASEBAND

IC

MODEM

CODEC

PROTOCOL

MMI

CONTROL

MEMORY

Block Diagram

© 2000 Micro Linear Corporation. All Rights Reserved.

10k

0200

PB2721-01

900MHz DSSS RF to Digital Transceiver Chipset