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Altera_Forum's avatar
Altera_Forum
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17 years ago

Output amplitute from an NCO

Am i right in thinking that the output amplitutde from the NCO is not constant over different frequencies?
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
17 years ago

Hold on...It could be you are having sinc effect of DAC's hold device.

DACs normally have inverse sinc filter to compensate for that.

But it could be you are right, as you get closer to Fs the amplitude will droop and becomes zero at Fs(in theory). So there is no problem now. Basically I missed the fact that your DAC is basic without inverse sinc correction.