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Honored Contributor
Honored ContributorClock Noise?
Hello, I am using a cyclone II fpga and have a 25 MHz clock going into a dedicated clock pin. I have a simple DFF to divide the clock by half to 12.5 MHz and i am looking at that output with a ...
Altera_ForumHonored Contributor
Honored ContributorHi Matt,
Do you mean noisy in amplitude or frequency? i.e. is it Jitter? What does the input clock like in both situations? Have you viewed the in and out clocks with an Oscilloscope? It sounds to me like a signal integrity issue. Do you run the clocks tracks near the PC104 on your PCB? Have you followed all the guidelines for PSU decoupling etc on your PCB? Sorry for all the questions, but hopefully it will give you some pointers of things to look out for.
