Virata preps 'Claudius' communications platform

Virata preps 'Claudius' communications platform
By Peter Clarke, EE Times
May 4, 2001 (6:34 a.m. EST)
URL: http://www.eetimes.com/story/OEG20010502S0039

LONDON — Virata Corp. (Santa Clara, Calif.) is planning a system-on-chip platform for broadband communications under the code name Claudius. The company is also developing a partnering strategy to extend its capabilities into wireless broadband applications, a departure from its traditional strength in wired communications.

Under the partnership program, Virata will work with Proxim Inc., Cambridge Silicon Radio Ltd. and Intersil Corp. to address the HomeRF, Bluetooth and 802.11b wireless LAN communications standards, respectively.

The Nasdaq-listed company, which has its engineering base in Cambridge, England, is developing Claudius as a platform of software and hardware intended to address residential and business gateway applications and as a step up from its series of devices based on dual ARM 32-bit RISC processors.

Such established Virata chips as Helium and Beryllium, designed into asymmetric digital subscriber line (ADSL) commu nication systems, typically use 0.35-micron and 0.25-micron CMOS process technology. Claudius is targeted initially at the 0.18-micron process node prior to porting to 0.13-micron and should be available in production volumes before the end of 2002, company executives said.

Virata has completed the design of its next Helium device, the Helium-220, for implementation in a 0.18-micron CMOS process technology and has received first silicon from its Southeast Asian foundry. The company expects the chip to become available in the fourth quarter.

The twin-ARM-based Helium and its latest derivatives, the Helium 200 and 210, can provide both ADSL-to-Ethernet and ADSL-to-USB bridging capability. But requirements are on the rise for routing and application-specific processing between the receipt and transmission of packets.

As companies field video services, multiple MPEG-2 and MPEG-4 video streams could need processing, routing or parking to hard disk, said David Moorhouse, director of product management at Virata. And firewall security and encryption for privacy and e-commerce could place large demands on the communications processor architecture.

Further, in light of the market uncertainty about business models for the rollout of digital gateways and therefore what feature combinations and chip-level partitions will make sense, Virata wants to continue its programmable, software-on-silicon approach.

"Helium is pretty much fully programmable," said Trevor Coleman, vice president of marketing at Virata. "Virtually all of the software is in C. Certainly the protocol code is provided in C, but with low-level code in assembler, because it's pretty heavily optimized."

When asked whether Virata is being cautious in its use of process technology, Moorhouse responded, "If you are working with a major such as Texas Instruments, you might be able to get 0.13-micron chips earlier. But with a Southeast Asian foundry there's an issue of access to intellectual-property blocks and libraries. They are only just becoming available from [Taiwan Semiconductor Manufacturing Co. and United Microelectronics Corp.] for 0.13 micron.

"The other issue is, Can you make use of all the die area of a 0.13-micron chip?"

A simple scaling of Helium could not make use of the additional gates available on a 0.13-micron die of economic size, Moorhouse said. That all but necessitated the Claudius project, he said.

Coleman noted that "at a high level, Claudius uses a very similar architecture to our existing Helium family of communications processors. However, at a lower level it does use a different design methodology and has many functional improvements.

"One of the benefits of the new design methodology is that Virata will be able to design a number of devices to suit different market segments more easily than can be done today."

When asked whether Claudius should be considered a chip or an architecture, Coleman answered, "Claudius is a new chip design that will form the basis for other designs in the future ."

Coleman said that all of Virata's major projects have been named internally after Roman emperors, roughly in chronological order but omitting the maddest and baddest. There was, for example, no Project Caligula.

Networking core

One aspect of broadband gateways could be addressed by a networking processor core or an array of network processor cores, either developed by Virata or licensed for use from another processor developer.

Traditionally, Virata has dealt in core licensing and has concentrated on the overall architecture of its system chips and the software that runs on them.

"It's an area we're looking at — to provide a more powerful network processor," said Coleman. "This is an area where we have a lot of expertise. But we have to get the market area right. I'm not aware of any potential cores we could license in, although it's possible."

An Israeli software development center acquired along with Inverness Systems Inc. (Marlborough, Mass.) in March 2000 has b een expanded and has recently moved to Herzlia, Israel, from its original base in Kfar Saba, Coleman said.

"When we acquired it, it was pure software. There are now about a dozen hardware engineers and a dozen in software," he said. "Their task is processor development."

Backing three wireless horses

To develop its skills in wireless communications, which could also play a significant role in gateway equipment, Virata has developed a partnering strategy.

The company has already announced a partnership with Proxim (Sunnyvale, Calif.) to create HomeRF-based reference designs for the residential DSL market.

Coleman said Virata has similar partnerships to pursue Bluetooth and 802.11b wireless LAN applications, respectively, with Cambridge Silicon Radio Ltd. (Cambridge, England) and Intersil Corp. (Palm Bay, Fla.).

"There is some uncertainty in the market about which of these [standards] will succeed," he said. "We are working with the RF chip providers and integrating with ou r broadband solutions. We provide the integration services and software drivers."

When asked whether Virata would consider trying to integrate RF circuits into its chips or chip sets, Coleman said, "It's good to learn about the market and what customers want. But I don't see us going into competition with our partners head-on. It's more likely we would find a way to cooperate with our partners."

That could take the form of licensing RF circuitry for incorporation within a Virata chip set, Coleman said.

At present, Cambridge Silicon Radio is committed to providing its Bluetooth transceiver technology in the form of a CMOS chip, although company executives have spoken about selectively licensing the technology.

Coleman pointed out that Virata is an investor in Cambridge Silicon Radio. If a deal could not be cut for Cambridge's Bluetooth transceiver technology he said, Taiwanese foundry UMC Group could provide a Bluetooth transceiver, through a deal with Parthus Technologies plc (Dublin, Irelan d).