We are doing some tests on AD9914 DDS Eval-board with 3.5 GHz single ended clock frequency. Also, we are comparing spurs and spur levels with ADI SIM DDS program on analog devices web page.
However, there is no phase truncation spurs (PPT) on our spectrum while the ADI SIM DDS correctly points out the PPT on the simulation and frequency domain legend.
We have tried DAC calibration tool on the eval-board control program, tried many different fundamental frequencies and so on. All try outs did not overlap with the calculated PPT.
Could you help us to figure out the problem that prevents us to find PPTs on the real hardware?