Is there any characterization data of the AD9914/15's DAC that can help me to inplement the inv sinc filter in Software?
Thanks and regards,
Unfortunately, there's no characterization data. If the AD9914 output is not externally band limited, the DAC output SINC roll off (within the 1st nyquist zone) to a first order should follow the theoretical formula for SINC roll off. Note, the AD9910 has an integrated inverse filter built in that can be enabled. That part has a maximum output frequenciy up to 400MHz.
I branched this question to a new discussion for better visibility in the community.
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There is a wideband SFDR values from low freq up to 0.45 of the clock freq in the datasheet, I hope this would be of help. Usually the SFDR rating is limited by the image frequency but that would happen when the fundamental frequency approaches the nyquist frequency. There are also instances that the SFDR is limited by the harmonics of the DAC, which usually occurs at low frequencies.
Thanks for your answer, but i think I was not clear enough, and we are not talking about the same thing here.
The AD9910 has an inverse sinc filter between the DDS core and the DAC, to compensate the intrinsic zero-order hold effect associated with the DAC generated signals. In the case of the 9910, tha shape was characterized and a FIR filter designed to do the job. (AD9910 datasheet table 6)
I know that the AD9915 does not have this feature, so I was asking if there is such characterization for the AD9915 output DAC, so I can implement the FIR filter and alter the amplitude to achieve the compensated signal. If you could publish the inverse sinc filter tap coefficients, as you have for AD9910, it would be an easy job to do it
Thanks and best regards,
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