I have a question for you.
As for your ADuM3470,
Your datasheet Fig-39 show the recommend external capacitor Cin=10uF.
But UG-197 show the recommened external capacitor C13=47uF.
Which is more better you think? Or how should we select these values?
In the ADuM347x datasheet component selection section we do say: The recommended capacitor for VDD1 is 10uF and for Viso is 47uF. The Vdd1 capacitor used on the UG-197 is 47uF, but 10uF will work as well, increasing capacitance to 47uF is OK.