The higher the duty cycle, the greater the average voltage being applied to the dc motor(High Speed) and the lower the duty cycle, the less the average voltage being applied to the dc motor(Low Speed).īelow image illustrates PWM technique with various duty cycles andaverage voltages. The average voltage is proportional to the width of the pulses known as Duty Cycle. PWM is a technique where average value of the input voltage is adjusted by sending a series of ON-OFF pulses. A common technique for doing this is to use PWM (Pulse Width Modulation) The speed of a DC motor can be controlled by varying its input voltage.

H-Bridge – For controlling rotation direction.

This can be achieved by combining these two techniques. In order to have a complete control over DC motor, we have to control its speed and rotation direction. In that cas the shield doesn't nothing Arduino is magic sometimes.One of the easiest and inexpensive way to control stepper motors is to interface L298N Motor Driver with Arduino. One theory is that I adjusted the tension of my power supply under 5V. I don't know why but now, the shield works too, I mean : Problem solved. I did tested the PWM with an oscilloscope and a multimeter, the arduino PIN I was using worked correctly. I feel a bit stupid with what I did with the grounds, it seems wrong t me but I don't know what to do instead :/ What can I do ? My goal is to have the best possible control of the speed of that DC motor in term of reactivity, does a L298N is suited for that ? Now here is the problem I have : With the scheme I've shown above, it simply doesn't work, nothing happens when I set the grounds in common, why ? Then if I remove the cable that goes to the arduino ground, it works but the motor has a very low torque, it seems also that there is a kind of latency in regards to what display the Serial monitor. This prooves at least that my shield isn't damaged.

If I doesn't use the Enable output of my Arduino and just use the jumper instead, the motor turns with a good torque. I'm aware that, maybe if the value is too low, the motor will have trouble to start so I 'help' it manually.

With that code, the speed of my motor should progressively increase and then goes back to 0. Now here is the code I'm using : #define CONTROL_M 9 // To Enable inputĪnalogWrite(CONTROL_M, i) // Any value between 0 and 255

I don't care about the sens of rotation, so I set IN1 to 5v and IN2 to the ground, is it right to do it like that ? The power comes from a transfo with an adjustable voltage of ~7v 1.0 Amp. I try to control the speed of a DC motor with a L298N shield but it doesn't work very well. (Not native english speaker here, feel free to edit my sentences)

Keyes l298n motor driver shield