This is a circuit that controls the speed and the direction of a 12v dc motor without the topology of the h-bridge ( it's an alternative to h-bridge ).
First the pwm signal is converted to a dc signal. The amplitude of this dc signal, the motor speed and the direction of rotation varies with the duty cycle of the pwm, that is, 0% duty cycle corresponds to 0v ( maximum speed on one direction ), 50% corresponds to 1.66v ( motor stops ) and 100% corresponds to 3.33v ( maximum speed on the other direction ). This dc signal is then amplified at both voltage and current levels. You can use an Arduino to provide the pwm signal. You can supply in the rails 15vdc and -15vdc or you can use an ATX power source of an old computer to obtain +12vdc and -12vdc but you have to adjust the gain in the op-amp.
This circuit uses only one pin of the microcontroller ( PWM pin ).
There are no codeArduino
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