Diff. Amplifier 2


This is an (untested) improvement upon Diff. Amplifier 1 and implements the "Signal Processing Module" from circuit 5.1 and circuit 6. Essentially it calculates the difference between the voltages at the "in1" and "in2" pins, after applying a high-pass filter through C1/C2, and a pull-up/down through R1/R2 towards Vref to base the signal around the center.

Part placement


The "out" pin goes directly to the Arduino ADC (or perhaps through a multiplexer)

The redundant Vref/GND/V+ pins can be used to wire multiple of these in a tree network topology, where only the first board needs to be directly connected to the power module.