Free Back Article: Precision Control for DC Motors
This control circuit will provide the correct rotational speed and direction of a 12-V DC motor. Nothing special in that? But there is definitely, when you consider the multitude of potential options for actuating the motor. You can adjust the speed manually with a potentiometer (‘pot’), using a DC voltage level between 0 and 5 (or 10 V) or even digitally using I2C.