Tom,

I may not understand the quandry, but it seems to me your question is where to connect AGND and DGND. I suggest you search the three main schools of thought about component placement and grounding. The first is from Analog Devices (www.analogdevices.com), the second is from Linear Techonology (www.linear-tech.com) and the third is from EMC Consultant, Henry Ott (www.hottconsultants.com). When you go to Ott's site, be sure to select the "Articles" section and read through the articles available online. I think you'll be quite pleased with Henry Ott's approach.

Bruce