So I've been doing a bit of reading on the reasoning for separate Vdd/AVdd and Vss/AVss pins, and I've come across lots of different solutions on how to use them.
I'm currently using a PIC18F1220 and I'm using the ADC with internal voltage references selected. I've read that if you're doing that, it's good to put a filter on the analog power supply pins. Others say you can direct connect the digital and analog supply pins together. Others say that as long as you're using bypass caps properly, then you're good.
Despite all of these differences, one thing everyone says is "According to the datasheet...". I can say that I've been through all 300+ pages of the PIC18F1220 datasheet and can't find anything about what to do with the analog/digital supplies. A separate Microchip document said that this type of information would be in the "Programming Specification" document, which they state is different from the data sheet. I haven't been able to find this document for the PIC18F1220.
So, the question is: What the heck should I do with the analog supply pins? I know they need to be connected in order for the device to operate, just not sure how.
I'm currently using a PIC18F1220 and I'm using the ADC with internal voltage references selected. I've read that if you're doing that, it's good to put a filter on the analog power supply pins. Others say you can direct connect the digital and analog supply pins together. Others say that as long as you're using bypass caps properly, then you're good.
Despite all of these differences, one thing everyone says is "According to the datasheet...". I can say that I've been through all 300+ pages of the PIC18F1220 datasheet and can't find anything about what to do with the analog/digital supplies. A separate Microchip document said that this type of information would be in the "Programming Specification" document, which they state is different from the data sheet. I haven't been able to find this document for the PIC18F1220.
So, the question is: What the heck should I do with the analog supply pins? I know they need to be connected in order for the device to operate, just not sure how.