Flash PIC with 12 bit ADC

[BrianT]

12 bit ADC operation should be easy with even relatively sloppy layout boards. I recommend you use a copper pour over the entire board tied to ground.

I have found an external 16 bit ADC is a challenge and needs very careful layout, separate analog and digital grounds, a copper pour tied to analog ground around the ADC and tied to digital ground in relevant areas plus software tricks like multiple averaged samples to get expected results.

One neat trick that has saved the day for me several times is to have a low voltage mains input and to time the ADC read to a zero crossing, or at least the same point in the mains cycle every sample.

HTH
Brian

[Charles Linquis]

The (new) 18F8723 has 12 bit A/D's