"You have to distinguish between a settlement and a licensing agreement," said Avo Kanadjian, vice president of worldwide marketing for Rambus. "Basically, the payments in an agreement should be better for the other companies than a settlement."

On Thursday, Rambus announced it had settled its dispute with Hitachi over patents in high-speed interfaces for synchronous DRAMs, double-data rate (DDR) memories, and microprocessors. Under the agreement, Hitachi will pay Rambus an up-front settlement fee as well as quarterly royalty payments for use of the company's patented interface technologies in those DRAMs and chip interfacing directly to the memories (see June 22 story).

The settlement will end Rambus' lawsuits against the Japanese chip maker in the United States and Germany as well as its pending case before the U.S. International Trade Commission (ITC). The precise terms of the settlement were not disclosed by the two companies.

Although Hitachi licensed Rambus data rights for its SDRAMs, DDR SDRAMs and H-series microprocessors, a company spokeswoman said the firm "doesn't admit that the Rambus patents are valid."

In an interview on Thursday, Rambus' Kanadjian said the Mountain View company will seek different levels of royalty payments from various IC producers for rights to its patents in synchronous memories and interfaces. He said Rambus is seeking royalty payments from all chip makers who may be using the firm's synchronous technology.

In addition to Hitachi, Rambus has struck a licensing pact with Toshiba Corp., which agreed to pay royalties for the interface technologies used in SDRAMs, DDR memories, and controllers (see June 16 story). Like Hitachi, Toshiba has agreed to pay royalties for those ICs at a higher rate than the same technologies used in Rambus DRAMs. RDRAMs are being promoted by Rambus as a competing high-speed, wideband memory format to DDR SDRAMs.

Rambus continues to emphasize its own memory architecture for the marketplace, but it is now willing to license its intellectual property (IP) for other memory solutions as well, according to Geoff Tate, CEO of the company. This approach of licensing its patents at a higher rate for non-Rambus DRAMs has stirred a debate in the industry.

Rambus officials have contended that the Toshiba licensing agreement and announcement last week had no bearing on the settlement with Hitachi. "There is no such thing as a standard licensing agreement," said Kanadjian. "Each company case is different. Hitachi and Toshiba have different licensing terms, and any new agreement may well have different terms."

Kanadjian said Rambus is "reviewing" if its synchronous technology that may be used by other manufacturers of SDRAM and DDR memories and it will seek licensing new agreements with them.

Virtually all DRAM firms, including Samsung, Micron, Hyundai, Infineon, and NEC, declined to comment about Rambus' stance. Fujitsu Ltd. and Mitsubishi Electric Corp. both said they were studying the Rambus licensing proposal, but had made no decision.