Connect with us

Why DDR?

Discussion in 'Electronic Design' started by avishay, Aug 21, 2007.

Scroll to continue with content
  1. avishay

    avishay Guest

    Hello everyone,
    I wonder if someone could explain me what's all the fuss around DDR.
    If you're driving data at double clock rate, why not feeding the chip
    with double clock (or DQS) rate in the first place? What do we gain
    from all the dual edge strobing mess?

    Thanks,
    Avishay
     
  2. Tim Williams

    Tim Williams Guest

    Idunno, but it's really big in Japan.

    Tim
     
  3. Bob

    Bob Guest

    The data rate is what is the most important factor. The faster the better
    (or so we're told).

    With single data rate, the maximum frequency content is always contained in
    the clock so it's the toughest signal to transmit. With double data rate,
    the frequency content of the clock now never exceeds that of the data.

    Don't get too excited about whether it's SDR, DDR, FDR, or BFD. The data
    rate is the thing that drives the technology. The clock rate is only there
    for support.

    Bob
     
  4. Eeyore

    Eeyore Guest

    Lower power consumption ? Simpler pcb layout ?

    Graham
     
  5. Paul Burke

    Paul Burke Guest

    Die DDR wurde in 1949 proklamiert. Die Kommunisten steuerten es. Seit
    Oktober 1989 ist est mit der Bundesrepublik Deutschland vereinigte.
     
  6. Hal Murray

    Hal Murray Guest

    You save a factor of 2 on the frequency of the clock signal.
    Since that's the fastest signal involved, the factor of 2 is
    important.
     
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day

-