Xilinx or Altera...

For Xilinx, yes. Check out the following link for reference designs and the Memory Interface Generator (MIG) tool.

DDR/DDR2 SDRAM

-- Steve Knapp

Or even easier use Alteras' DDR2 megafunction

Slurp

Dear Slurp, I do not know what you mean with easier, but the Altera design promises only 267 MHz max, that is 20% slower than the Xilinx design at 333 MHz. Nice try! Peter Alfke, Xilinx

Peter,

I'm a bit confused. Do you tell now that you can get as high as DDR2-667 on a Spartan3 device? Or did you actually mean on a V4?

Regards,

Luc

Luc, let me un-confuse you: I referred to Virtex-4, but why do you ask? The OP did not specify a device family, and Virtex always outperforms Spartan. And Spartan is always lower priced than Virtex. That's why we have the two different families. I do not understand the reason for your question.

Peter Alfke, Xilinx Applications

Sorry, based on subsequent postings, I'd like to clarify that a 333 MHz DDR2 (667 Mbps) solution exists for Virtex-4.

In specific, take a look at XAPP721 and XAPP723, which use the ISERDES and OSERDES features in the Virtex-4 I/O block.

XAPP721: High-Performance DDR2 SDRAM Interface Data Capture Using ISERDES and OSERDES

XAPP723 - DDR2 Controller for ISERDES and OSERDES Interface Using Virtex-4 Devices

For Spartan-3 fans, DDR2 SDRAM interfaces operate at 167 MHz (333 Mbps) using the -5 speed grade. For this solution, check out XAPP454, which also includes a reference design.

XAPP454: Spartan-3 DDR2 Memory interface

-- Steve Knapp

To clarify, Altera's posted DDR2 SDRAM controller supports operation up to 267 Mhz. There is another core that supports 333 Mhz operation available by contacting your local sales rep.

Paul Leventis Altera Corp.

Hi Peter, Indeed, I was confused. I saw Steve's reply and was unwillingly referring to Spartan3. There started the confusion. My appologies.

Luc

Thanks for the confirmation Paul, am already using it!

Slurp

Please see reply below

Slurp