I have just registered here, so greetings to y'all! In my spare time, I've been fiddling around with AVRs for quite some time now, and in a recent project an unused pin smiled back at me while all the other pins had already been assigned: the AREF on an AtMega16.
I don't use the A/D converter in this project and according to he docs, the analog reference, even if generated internally, is supplied to this pin. So basically, with the right config, I can switch the AREF pin to 0V (chip programmed to use external AREF) or to VCC (AREF = AVCC selected) etc.
The question is: how much current may I suck from this pin? The normal outputs can drive an LED, so 20mA are not problem. But the AREF pin? Kind of strange, I know, but has anyone done this? I guess it is common to drive a sensor from this pin, no? If the internal 2,56V reference is selected? So why not drive an LED? Even with a transistor that switches my LED, I would be pleased, because it would be a solution.
Does anyone have some experience with this idea?