Picture for reference is below. I'm confused as to how this is able to receive a differential voltage of +/- from a single power supply. (Yes, I know the picture says dual power supply.) Normally I have to short the negative to ground on one side of a dual power supply, and short the positive on the other side of a power supply in order to get a +/- Vpower to an op amp. I actually wired up this evaluation module with just using one side of a power supply and it worked. There were no rails on either side. Looking at the circuit board: http://www.ti.com/lit/ug/slou148/slou148.pdf I'm not entirely sure how it is able to do this, or how the circuit would look.