Can the EXTIO Pin be left unconnected if not used? Or must it be connected to GND through a 0.1uF capacitor.
Also, the datasheet does not have any recommendations as far as the bypass capacitor network is concerned, nor does it mention anything about capacitance built into the package. I looked at the reference board and it appears to have an unusually high number of bypass capacitors on each rail and very large values at that, such as 10uF and to a lesser degree 0.22uF, which do not help decouple in the 500MHz range that this part samples at. Is there a more proven decoupling scheme for this part which has been verified in the lab and contains not only a smaller number, but also more appropriate values for decoupling at the max sampling rate?