Mixed digital/analog rails and level-shifting components best practices
A star (single-point-common) ground is a traditional approach, but somewhat heavy handed.  Openings in the ground plane can cause other EMC problems for traces which cross this boundary unconditioned.

The main point is to keep digital noise from sensitive analog circuitry.  Return currents in ground paths can result in small voltage differences.

The modern opinion (since it's not so absolutely clear that either is best in all cases) is to use a single, low-impedance ground plane and use routing rules to separate your digital returns from your analog.  Small current loops, such as those in switching supplies, should be as tight as possible and connect at a single point to the plane, so the large loop currents don't disrupt the surrounding circuitry measurably.

Needless to say, digital and switching signals should be as far as possible from the sensitive analog signals, but you don't have to be obsessive about it.  They're coexisting fine on the chip, which is smaller than the board.

Try to pick an IC that has largely digital signals on one side, and the most sensitive analog signals on the other, it makes layout easier.  Most of the new ones observe this protocol.

Finally, some guard traces around the analog inputs may reduce the crosstalk even further if needed.