Does the AD9633 have any indication of an Over Range / Clip condition? The behavior that I am seeing is that the ADC code seems to wrap back to zero (using Offset Binary).
Thanks for looking at the AD9633. It does not have an overrange indicator, other than looking at the output codes.
Are you using the AD9633 evaluation setup from ADI? If so, you could use the Logic canvas in VisualAnalog to see which codes are being produced when you see the wrap-back behavior.
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