I'd stack up the PCB with the ground plane very close to the signal layers. And the bottom is the star earth layer with a large gap between it and the other layers. Has anyone ever done this and have any suggestions to me?
Putting the low signal stuff on its own section of ground plane, the inductive switching stuff on a separate plane and then the PIC and its associated stuff on yet another section of plane then starring each of the ground planes back to the main heavy current that's got to go right across the PCB.
If you're using the PIC ADC for anything, it's a good idea to avoid noise going past it. In that case, you might route the other currents around the PIC plane.
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