>
>So my question is this: I want to make the back of the board another
>ground plane, just for (hopefully) improved shielding. There will only
>be one connection to it, but I'm not quite sure where to pull it from,
>the analog or digital ground? So far, the best idea I've come up with
>is to use the ground from the input to the regulators to ground the
>back of the board.

Try to find a point that dosen't have a bunch of noise on it.
Your common point back at the power supply should be ideal.
Otherwise, you'll be an antenna for whatever noise is on the "ground" at the point you tap it.

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