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I am considering using a chip, but the datasheet is confusing me as it has several distinct power pins.
It has:
How do I hook up each? Do I connect AVDD straight to DVDD, and what about PLL_VDD, and the ground pins? The suggested schematic seems to show them all connected to the same potentials (with different symbols for both types of grounds); from a cursory glance it doesn't mention anything about PCB layout. So how should I wire it up?
Divide your board into those discrete sections: PLL, Analog, Digital, and IO. Try to keep all of the copper (signal & power) for each section separate except where they require interconnect. Join the power to each sub-circuit only at near the power supply, within the sub-circuit and at chip when possible. Bypass each at the chip grounds with a cap or two (you might leave an extra footprint here for test).
You may find that the layout doesn't permit total separation of sub-circuits. If so, at least try to use a wider trace to supply the split and filter where necessary.
I'd filter the AVdd supply to minimise noise. The data sheet has a schematic on page 80 which shows all the connection details. Careful PCB design will be required, I wouldn't bother unless you have a lot of PCB design experience.
