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Altera_Forum
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16 years ago

16MHz crystal and PLL or 64MHz crystal?

I'm using a Cyclone II (EP2C5T144C8 to be precise). It's being interfaced to an external chip B. External chip B communicates with the FPGA over LVDS, and supplies both data and a clock through ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

After some consideration I decided to go with the direct 64MHz approach, even invest in a more expensive crystal (64MHz 25ppm), in order to avoid harmonics in my RF circuits (now I have to deal with 64MHz harmonics, and not with 16MHz harmonics plus whatever the PLL generates due to the multiplication by a factor of four).