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Altera_Forum
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20 years ago

SRAM vs SDRAM

Hi, I am about to design a system with uClinux, and I was wondering if the performances would be correct if I only used an SDRAM. SRAM is a bit expensive if I want to have enough memory to run...
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Altera_Forum
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19 years ago

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originally posted by jdhar@Feb 20 2006, 12:11 PM

what kind of power restrictions are you on? i persoally don't think ddr is too heavy on power... that is, without using vtt termination. i doubt you could get to speeds high enough to require vtt termination, unless you had multiple chips banked.

maybe ddr2?

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Thanks Scott, I agree, a PSRAM IP block from Altera would be very nice!

jdhar: I have looked at DDR and DDR2, though I can only go on what the data sheets tell me as I&#39;ve no personal experience. In our battery powered app a 256Mb DDR looks like taking anywhere between 300mW and 600mW, whereas the equivalent amount of PSRAM takes no more than 120mW.

I don&#39;t really need the full DDR speed, I just want to be able to run one or several NIOS processors at around 80MHz without incurring too much slow down due to slow RAM. PSRAM in burst mode looks like it could be a perfect match, but I&#39;m still in two minds.