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Altera_Forum's avatar
Altera_Forum
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15 years ago

How to make DDS with NCO megacore function?

I try to make square wave with NCO Megacore Function as below. But, The square wave is not good for use like dds. How to make square wave like ad9850 dds ----- below is VHDL Code -------...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

You're requirements aren't clear to me.

Do you need the sine output or only a variable clock?

Do you need a low jitter, analog interpolated clock or would a fractional clock be sufficient, as generate by your above example code? In the first case, you need all the analog stuff, e.g. a DAC and a low-pass filter, and using a DDS chip means less effort.