I have designed a built a dual-channel DDS function generator board using two AD9834 ICs to produce the channel output waveforms. So far my REV A board has been functional in terms of communicating with the DDS ICs and modifying the frequency, phase, and toggling between sine/triangle output.
My problem is that when the IC is outputing the sine wave or triangle wave, it looks extremely distorted as if the internal SIN ROM was misprogrammed. I attached a scope shot showing the output waveform for reference along with the portion of my schematic showing the DDS and output filter). Has anyone ever seen this anomaly before?
Research & Development
Resonance Group, ltd.