I am using ZCU102 + AD9144-FMC-EBZ, in JESD mode 0, with meta-adi linux.
When I use the DAC-FMC-EBZ reference design, I get a jittery sine wave on the scope:
I turn off one of the tones, and put the other at scale of 0.8 and 40 MHz,
and I see that the sine wave is "breathing" - its maximum amplitude is going up and down.
When I draw a histogram of the voltage peak-to-peak of my sine, it is quite wide,
with values from 1.04V to 1.047V. (7mV jitter)
I haven't changed anything in the reference design, and was excepting much better performance.
(Our red pitaya and waveform generators give us much more stable sine wave).
What can be the source for this?
I thought it can be the clock source- is it OK to use a 2GHz sine wave as the source (or does it have to be a square wave?)?
Any idea or direction to get rid of the noise will be very helpful,
Moved from High-Speed DACs to Linux Software Drivers on Thursday, November 16, 2023 12:37:52 AM by JMMina