The customer has two questions about DAC CAL of AD9915. Could you please let me know the answers ?
Q1. How to optimize the setup and hold times for internal DAC timing ?
Q2. Whenever DAC CAL works, the output phase is inverted. Is it correct work ?
Q1. Toggling CFR4 (0 ==> 1 ==> 0) executes the DAC calibration process, which automatically optimizes the setup/hold internal to the device.
Q2. I am not sure what you mean by an inversion of the output phase, but I suspect the output was incorrect ("inverted") prior to executing the DAC calibration and assumed the proper phase once the calibration process occurred.
Thank you very much for your support. I've got the picture of the inversion as follows.
The bottom waveform is the output memorized each DAC_CAL. The colors are Orange, Green and Brown.
If you have some comments, please let me know.
The 'scope appears to trigger on the BLUE trace. What is the source of the trigger signal?
What is the signal source for the GREEN trace?