I am having trouble finding a circuit diagram which will control the position and speed of a 12v 10 amp motor, running off a 12v car power supply. and using potentiometers for feedback, gain and output. The transistors have to be able to switch high amps and the op-amp will, I believe, need a dual power supply.

 

Hi Laurence Shouldn't be a problem, there are lots of good rail to rail opamps available and you can up-reference your feedback . The motor can be bridged to simulate bipolar operation. Check out the IC houses that sell h-bridge components, etc. Someone should have a unipolar application note. I would expect the vendors of power linear stuff should be helpful as well. If you have a circuit you would like to convert, let me know. I'll try to help. Regards cww