Hi,
I'm getting high frequency noise on my sine wave:
Can anyone verify if my settings are correct?
Hi Andrew,
If you are referring to the stair-case steps on top of your sine wave, these are due to the DAC being a sampling system with sample and hold circuit. The DAC basically takes a sample, create a appropriate quantized voltage, and hold the value until the next sample. This will be the case for all DAC devices. These high frequency stair-case steps are actually the higher Nyquist images being folded outwards in frequency.
I see there is about 7 or 8 steps within the 20ns division on the scope plot, this translates to about 380MHz of sampling rate, which is what you are using. The best way to eliminate this stair-case steps is to attach a anti-aliasing filter at the output of the DAC to filter out high frequency noise.
The following link offers more explanation:
-Kang
