The current sensing portion of the project is on hold for the moment while I await delivery of a Hall effect device from Spark Fun. It's their breakout board with an Allegro ACS712-5A surface mounted to a PCB with wide traces for a decent amount o...

This is my current (ha! get it? current? tap, tap. is this mic on?) circuit diagram for sensing the amount of current going through a shunt. I posted a question to the Adafruit forum about how to get it to work. Apparently op amps don't work well ...

This is a chart showing the non-inverting input voltage (mV) versus the output from the op amp, as read by the Arduino (0-1023). With the correct gain multiplier the op amp does vary the output as the input voltage changes. However, it's extremely...