Op-amp Arduino Shield

Recently I needed an op-amp front end for taking some measurements using a bpw34. I put together a circuit on a  bread board, took the measurements, then put all the parts back. I decided to build a shield that can be configured for two or three different op-amp configurations, then feed the signal into A0. The core circuit uses a LM358D with a soic footprint. All other parts are thru hole. There is some prototype space, and two additional soic-8 footprints.

The LM358 has two op-amps in it. They are chained together, One could bypass the first or second stage by soldering a jumper.The second stage has a voltage divider that brings the input voltage to Vcc/2. The second stage also provides some feedback (if you solder in R6 and C4). This and a few other changes provide about six permutations of highly useful op-amp circuits.


opamp arduino shield

My first draft has a few minor errors, but is usable.  The next step is to write a comprehensive manual that lays out multiple use cases.