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Altera_Forum's avatar
Altera_Forum
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9 years ago

Interfacing to single DDR4 SDRAM device

Hi,

I am planning to design a board with Arria-10 GX FPGA and a single DDR4 SDRAM device, part no. MT40A1G8PM-083E. This doubt may appear silly, but I want to know whether I can have a functioning interface with just this single x-8 DDR4 device. Can I do away with multiple devices, fly-by topology, etc. I am asking this because I have never seen any board with just a single DDR4/DDR3 x-8 device. There will always be either a SODIMM (which has 4-8 devices), or an array of 4-8 devices soldered on the board. Just a single device will suffice for my memory needs (upto 1 Gbyte) and it will save me the headache of huge number of parallel lines and signal integrity issues.

regards,

rajesh

3 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    9 years ago

    I've never done that, but I don't see any reason it wouldn't work. Your performance will be terrible, though. Make sure you verify that your memory controller IP supports a single 8 bit chip.

  • Altera_Forum's avatar
    Altera_Forum
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    9 years ago

    Hi Galfonz,

    I am eager to know what makes you think that the performance will be terrible. If the interface is 1066, it means that I will have 2,133 Mbytes/sec (for x-16 chip). Considering highly pessimistic overheads of even up to 75%, I will still have more than 500 MBytes/sec. Don't you think this is huge enough. In my application the data rate coming into the board is only 50 Mbytes/sec. I need to do some processing, and some intermediate storage. Don't you think a single device will be good enough.

    regards,

    rajesh
  • Altera_Forum's avatar
    Altera_Forum
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    9 years ago

    Sorry, I should have been more specific. With one chip in x8 mode you are only transferring 8 bits at a time. You can get better performance running a wider data bus.