I finally got the bugs out of this circuit and installed it in the machine but after ten minutes of perfect operation I lost my speed control and found the LM358 had failed. I don't know if there is some kind of protection I can add or if my design is flawed and the IC won't survive in this application. I will upload the latest schematic showing values and additional components. Visit my last thread to get history on this project. Note: ignore my original problem with inverted output. It turned out I needed the outputs to go high when inputs were equal. The Motorola LM358N did this for me and was stable. My question now is what steps if any I can take to protect the IC. I should also add that I utilized a relay that will swap the polarity of the feedback pot when forward or reverse is selected. This was necessary to maintain convergence with the signal from the command pot. thanks
http://forum.allaboutcircuits.com/showthread.php?t=53838
http://forum.allaboutcircuits.com/showthread.php?t=53838
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