shift clock on AD9102

I' using an AD9102 evaluation board with an AD9914 drived by a 10 Mhz clock for generating a 39.0625 Khz sinusoidal signal.

Reading this signal by an AD7760 ADC drived by the auxiliary output of the evaluation board (10 Mhz CMOS) sometime I note a shift phase between the two system. Typically the shift corresponds on 1,4 degrees in delay that is exactly one clock pulse of 10 Mhz. 

It is possible the lost of some clock pulse input?

The problem increased in case of external noise like turn on near lamps or putting a groud shield on top of the board

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    •  Analog Employees 
    on Oct 11, 2018 3:07 PM over 2 years ago

    Most scopes have 8 or 10-bit resolution, but they are sampled at 100s of MHz or faster, and should have no trouble resolving 1 clock cycle at 10MHz. You only need to look at the zero-crossing, so resolution isn't important.

  • Correct !

    But I'm using a 24bits ADConverter like AD7760 because i need a phase resolution better than 1 millidegrees and only a >10Ghz scope could help me!

    I found a problem with the ground of the oscillator (TAITIEN NA-10M-2503) driving the AD9102 evaluation board. Is it possible that the sudden increase of the power supply of the thermocontrolled system generates a glitch on the 10Mhz output and only one of the two output of the AD9514 (one for AD9102 and one for AD7760) repeats the noise signal ?

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  • Correct !

    But I'm using a 24bits ADConverter like AD7760 because i need a phase resolution better than 1 millidegrees and only a >10Ghz scope could help me!

    I found a problem with the ground of the oscillator (TAITIEN NA-10M-2503) driving the AD9102 evaluation board. Is it possible that the sudden increase of the power supply of the thermocontrolled system generates a glitch on the 10Mhz output and only one of the two output of the AD9514 (one for AD9102 and one for AD7760) repeats the noise signal ?

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