I am building an application that powers the ADuCM355 via isolated power from a ADM3260. I'm looking for a power supply topology and circuit that offers the most reliable and accurate operation for the ADuCM355.
The ADM3260 datasheet is clear that 0.1u and 10u bypass caps are needed "close" to the VISO pin of the 3260. Also, the ADuCM355 data sheet recommends a 100nf cap at each power pin and a 4.7uf cap at the source. However after those recommendations, I'm seeing lots of conflicting examples. In the data sheet for the ADuCM355 on p. 27 there is a diagram of attached passive components and it shows power going through an "IS RES" (what's that?) at the source and then having a collection of beads and doubled 100nf caps and 1R6 resistors in a topology that violates the recommendation on the previous page of using single 100nf caps, plus makes no sense since some DVVD paths have the resistor and some don't without explanation. The CN0428 schematic shows a different power topology for the ADuCM355 than the data sheet, is that because CN0428 requires less analog accuracy? All in all, quite confusing.
So, aside from explanations of the confusing and conflicting power bypassing/cleaning topologies I mentioned above, I would like to know if any special filtering is necessary between the ADM3260 and the ADuCM355. The ripple and noise specs of the ADM3260 seem high for the input to an AFE (analog front end), is this why there are all the additional resistors and capacitors I see on example designs (including CN0326 which is a similar circuit and has a 10uF/100nf cap pair at each power input?)