Rambus to license serializer/deserializer for networks

Rambus to license serializer/deserializer for networks
By Robert Ristelhueber, EE Times
April 5, 2000 (2:33 p.m. EST)
URL: http://www.eetimes.com/story/OEG20000405S0022

SANTA CLARA, Calif. — Rambus Inc. introduced its first non-memory product on Tuesday (April 4), a quad serializer/deserializer (ser/des) cell that it hopes to license to ASIC vendors for use in high-speed networks.

The 3.125-Gbit/second cell is "our first chip-to-chip technology that has nothing to do with DRAM," said Kevin Donnelly, vice president and general manager of the Consumer & Communications Product Division of Rambus (Mountain View, Calif.). The product is part of Rambus' plan, first discussed last December, to move beyond the PC and videogame markets.

Currently, most OEMs use discrete ser/des chips from Texas Instruments Inc. and other vendors to connect line cards in the backplane of networks. But as the number of ser/des devices required per line card increases, that creates a significant pin-count issue, Donnelly said during a press conference here.

The ser/des cell c an support the 10-Gbit/s full-duplex data rate used in network line cards supporting OC-48, OC-192 and higher data rates, with 25 percent greater performance at lower power than discrete solutions, he contended. The cell was created by a design company called ASL that was acquired by Rambus last year, Donnelly said.

The ser/des cell will carry about the same 3 to 5 percent royalty as the Rambus ASIC cell, which interfaces with the DRAM, said Rambus vice president Subodh Toprani.

"Rambus is following the same path as Intel," said Bob Merritt, an analyst with Semico Research (Phoenix). "The PC is a great market, but it's time to shift into some markets in the communications area."

Unlike the direct Rambus DRAM interface, which has fought an uphill battle to be widely accepted, "Ser/des is a well-established technology, so I suspect the Rambus effort will slide in fairly easily," Merritt said. "The backplane issue is a valid concern as we get faster." He predicted, though, that the ser/des cell won' t produce as many royalties for Rambus as its DRAM technology.

Rambus also disclosed one of its first tangible successes in the communications market, a new network processor that incorporates the Rambus DRAM interface. Called the Prism, the chip was introduced by Sitera Inc. (San Jose, Calif.) earlier this week. Other network processor companies, including Extreme Packet Devices (acquired by PMC-Sierra) and Orologic (acquired by Vitesse Semiconductor), are also developing products that will use the Rambus interface, Donnelly said. He declined to say whether Intel will include the Rambus interface in its upcoming network processor.