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Honored Contributor
Honored ContributorPLL output square wave distorted
I am testing PLL output from an old Stratix board. The PLL has an onboard 80MHz crystal as input clock. However at > 60 MHz, the PLL output is not as square as I wish with ripple and 50mv u...
Altera_ForumHonored Contributor
Honored Contributoryou did not tell us which scope was used for measurement.
Your scope should have sample rates of at least 2.5 GS/s. What kind of probes did you use ? Be aware that the characteristic impedance of the transmission line used on your PCB is important and how it is connected to your chip.
