Motorola readies ADSL video IC for '97 entry

Electronic News, May 6, 1996 by Crista Hardie

Austin, Texas--Motorola's semiconductor group revealed a single-chip video transceiver scheduled for early 1997 release: an asymmetric digital subscriber line (ADSL) device designed to enable video-on-demand and Internet access over existing telephone wires.

The design is described as highly integrated and very low power. A separate Motorola business unit is developing a line driver for use with the ADSL transceiver, Electronic News has also learned.

Motorola's ADSL chip will be capable of speeds up to 8-megabits per second and will support ISDN, ATM and variable rate--an emerging technology for digital modems that allows the phone company to set the data rate. Fashioned using 0.5-micron mixed-signal CMOS process, the chip will draw on Discrete Multi-Tone (DMT) technology Motorola licensed last year from Amati Communications (EN, April 10, 1995). DMT is said to protect transmission channels from the signal noise that occurs at high speeds.

"The real benefit of DMT is it has better noise immunity and can go longer distances at higher bit rates. It has been proven in the standards to out-perform CAP technology, which is the other alternative," asserted Debbie Sallee, Motorola's ADSL business development manager.

General sampling of Motorola's ADSL device is slated for 1Q97, with volume pricing targeted at $85 per chip. In addition to Motorola, Orckit Telecommunications, Analog Devices and Alcatel are also said to be pursuing developments using DMT.

CAP, or Carrier Amplitude Phase, is a competing data encoding and compression technology supported by AT&T Paradyne. CAP was adopted by the ATM Forum as the standard for 51Mps transmission over Category 3 unshielded twisted pair (UTP) wiring.

Meanwhile, Motorola's technology partner Amati, which provided development support for the ADSL chip, last week announced plans to incorporate the device in its next generation of Overture high-speed multimedia modems, expected to reach the market next year.

And Ericsson Schrack Austria, which provided Motorola with systems requirements know-how, is also readying an ADSL access solution, dubbed COBRA AT 8, based on the planned Motorola chip. Ericsson will integrate the COBRA AT 8 in its broadband access system designed for Fiber-to-the-Curb/Building (FTTC/B) and Hybrid Fiber Coax (HFC) solutions, the company said.

ADSL modem technology makes it possible to transmit video and multimedia over POTS (plain old telephone service) lines. The current U.S. and European standards provide for transmission at 6.1 megabits-per-second downstream (from central office to home or end-user site), and 640 kilobits-per-second bi-directionally over distances up to 12,000 feet.