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Honored Contributor
Honored ContributorProblem with a pll
i have a new prototype of my own board with a 2c20-8 inside, at 49Mhz. testing the sdram, i found the pll lose cycles, and the clock signal to the sdram is erroneus (the high time is double than t...
Altera_ForumHonored Contributor
Honored ContributorWe had a lot problems with cyclone chips access to SRAM. As far as we tested the problem was with bad power supply decoupling. Check Altera provided recommendations.
Switching a lot of pins from 1 to 0 sinks a lot of current from capacitive loads on pins, causing quality deterioration of the in-chip ground (crashing the processor in our case). We did not have any problems with Cyclone I chips, so it seems that Cyclone II are much more prone to such problems. IzI
