Xilinx or Altera...

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Has anyone implemented DDR2 333Mhz (667Mbps) using Altera or Xilinx FPGA's


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Re: Xilinx or Altera...

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

DDR/DDR2 SDRAM
http://www.xilinx.com/products/design_resources/mem_corner/resource/xaw_dram_ddr.htm

-- Steve Knapp


Re: Xilinx or Altera...

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http://www.xilinx.com/products/design_resources/mem_corner/resource/xaw_dram_ddr.htm
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Or even easier use Alteras' DDR2 megafunction

http://www.altera.com/products/ip/iup/memory/m-alt-ddr2_sdram.html

Slurp



Re: Xilinx or Altera...
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


Re: Xilinx or Altera...
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


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Re: Xilinx or Altera...
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


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

Luc


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Re: Xilinx or Altera...
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.


Re: Xilinx or Altera...

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Thanks for the confirmation Paul, am already using it!

Slurp




Re: Xilinx or Altera...

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Please see reply below

Slurp



Re: Xilinx or Altera...
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
http://www.xilinx.com/bvdocs/appnotes/xapp721.pdf

XAPP723 - DDR2 Controller  for ISERDES and OSERDES Interface Using
Virtex-4 Devices
http://www.xilinx.com/bvdocs/appnotes/xapp723.pdf


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
http://www.xilinx.com/bvdocs/appnotes/xapp454.pdf

-- Steve Knapp


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