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Altera_Forum
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16 years ago

SOPC HP DDR2 Controller Clock Rate

I've installed a HP DDR2 Controller in the SOPC Builder. I'm curious what clock rate I can run this at. My memory can run at 400MHz CL = 3, 533MHz at CL = 4 and 667MHz at CL = 5. I'm running the c...
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Altera_Forum
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16 years ago

The distinction is this:

rogerleo is referring to fMAX.

The table in the Micron datasheet is referring to data rate.

fMAX refers to the maximum frequency the memory clock can be run at. This corresponds to tCK in the Micron datasheet. Data rate in MHz refers to the maximum frequency at which the DQS data strobe can run, which also implies DQ and DM. And of course this value is always twice fMAX or 1/tCK.

Jake