I am in the middle of my senior design project which is only a current measurement device capable of measuring current accurately from .5mA up to 20 A. I decided to go with using several different sizes of hall-effect sensors and switching between them based on the incoming current. I decided to go with using an Arduino Due because of the simplicity that the DAC pins give me.
Well, now that you know a little about my project, the issue I am having is that all of the current sensors output 5 volts analog and the Due can only read 3.3 volts. I've found that the Aref pin is unable to used on the due. I also don't feel like just using a voltage divider will give me the accuracy that I want.
My question is...is there a quick and nerdy, yet accurate way to read these 5 volt analog signals with my Due. If this is really easy to solve, just remember I'm still a student and unaware of a lot of the shelf technology that's out there.