Rambus and DDR RAM writeup

jerkychew writes "Hannibal over at Ars Technica has written part 3 of his RAM guide,, this time focusing on the technical details of Rambus and DDR RAM. As always, a good (if compliacted)technical read. " If you're not scared of pin counts and parity, then this is a cool article.

Comments

Re:DDR SDRAM? Not until the lawsuits clear ...

[ErMaC]

Here's the dirt:

Rambus is a member of the JEDEC, a committee of Semiconductor manufacturers which was created to help set standards for different types of chips. All the major manufacturers are JEDEC members, as well as other companies including Intel and Rambus.

One of the agreements to joining the JEDEC is that you must disclose all patents, finalized and pending, to the committee and you may not withhold such information, or use information gained in the JEDEC forums to file your own patents.

Rambus decided not to follow the agreement, and instead filed a patent during the SDRAM standard negotiations which would attempt to patent the exact implementation of SDRAM which was being written up. In the patent office, if your patent is not granted you can get extensions on it by modifying it. So what they did is continually string the patent along for several years, modifying it slightly so that as the SDRAM (and later DDR-SDRAM standard) was finalized, their patent looked exactly like what the standard was supposed to be.

Now the patent finally went through (god bless those morons in the patent office), and since everyone has implemented their RAM according to the standard, Rambus is suing them all for patent infringement.

However, there is very little chance they'll win. First, they violated the JEDEC agreement. Second, there is certainly prior art. Third, there was a decision back in '96 (I think) against Dell Computer when they patented something which was the result of "An Industry-wide Standardization effort" where the courts ruled that their patent was unenforceable. This is going to happen to Rambus, as well.

As for Hitachi and Toshiba backing down and paying license agreements there are specific reasons.

After the settlement, Hitachi sold their RAM division to NEC. They don't have to deal with the problem now, and since NEC is incorporating Hitachi's RAM infrastructure into their own, the licensing agreements probably mean jack now.

Toshiba, on the other hand, manufactures the RD-DRAM which is used in the PlayStation 2. They're making enormous amounts of money from this, and if they didn't agree to pay more licensing fees to Rambus, Rambus might pull their RD-DRAM license, thus forcing Sony to find someone else to manufacture the RAM.

Hope this has been informative...