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Frequently Asked Question

Why do I see reference spurs?

Reference spurs occur at multiples of the frequency of the PFD and can be caused by any number of things:

If the STATUS output is enabled and the PLL MUX is used to export a signal that is not DC, then this signal may couple to the clock distribution section. It is recommended that the STATUS output be used for static signals (such as digital lock detect) in applications where one is sensitive to PLL spurs.