Hello I am looking for some guidance on programming and using the Uno R3 board. What I want to achieve is for automotive 12-13v usage, however I want it to read a 0-5v sensor. In that 0-5V range I want the circuit to open or close at adjustable set voltages ie. closed at 0-4V open at 4-5V. Of course it can't draw any amperage from the sensor itself as that would affect the reading. Can anyone please point me in the right direction for doing this?