Q
T33, The hold time for A0, A1 do not seem to be correct or aligned to the parameters.
A
It should be related to SPI clock and not the CLKIN frequency. A0 and A1 should hold their value for the duration of the data read and after that they can be released or set to a new state. Upon review and analysis wrt AD2S1210 datasheet. There appears to have typo errors in the timing parameters. Have liaison with the author for this datasheet. The hold time for A0, A1 should be related to SPI clock and not the CLKIN frequency. Currently the datasheet is being revise to include these changes. Please see attached temporary cut down version for the time being.