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Minimum Speed of DDR / DDR2 SDRAM w/o DLL

I have been unable to find a definitive answer for this in my searches. I would like to operated DDR2 SDRAM below its minimum specified clock rate, which is usually 125MHz (DDR250). I assume that the minimum clock rate specified has nothing to do with refreshing but has to do with the lowest rate at which the DRAM's DLL can lock. I am wondering if I can operate below the minimum rate if I turn off the DLL. As far as I can tell, the only purpose of the DLL is to ensure that the output DQS strobe and the data are aligned with the input clock, so if I don't care about that relationship I should be able to disable the DLL. Anybody know for sure?

-Kevin

Reply to
Kevin Neilson
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Ya you are right, but for initilisation process you need to enable and then can disable the DDR DLL, once in active state, you can work , the only thing is you make sure all the timings still maintained with min operating freq with margins, because we are not sure of the internal timing paramenters

Reply to
asicbaba

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