I know that it monitors the incoming clock because you can read it out from some registers, but what is the behavior at 297MHz? Does it explicitly stop operation out of spec?
The device is only tested to 3GHz input. More then likely you will get strange results since the data rate will be going above 3GHz.
I realize that operation is not guaranteed, claimed, expected,suggested, or implied at above 297MHz, but does the chip have the behavior that it explicitly checks the clock and says "ah, I see something too fast, I'll ignore/powerdown/decimate the input instead"?
The comment from the ADV7619 expert
It will either not work or it will break.
Most likely it will not detect freq above 3GHz as frequency limiter is off...
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