Two push button switches are connected to 1st and 2nd pins of PORTD which is used to control the duty ratio of the generated PWM. Pressing the UP switch increases the duty cycle, which increases the motor speed while pressing the DOWN switch decreases the duty cycle, which decreases the motor speed.

How does PIC microcontroller control DC motor speed?

Two push button switches are connected to 1st and 2nd pins of PORTD which is used to control the duty ratio of the generated PWM. Pressing the UP switch increases the duty cycle, which increases the motor speed while pressing the DOWN switch decreases the duty cycle, which decreases the motor speed.

What is PWM DC motor speed control?

Pulse-width modulation (PWM) or duty-cycle variation methods are commonly used in speed control of DC motors. The duty cycle is defined as the percentage of digital ‘high’ to digital ‘low’ plus digital ‘high’ pulse-width during a PWM period.

How can we change the speed of a DC motor using PWM in PIC?

A variable resistor is used to change the duty cycle of PWM. By moving the knob of a variable resistor you can change the duty cycle which is directly related to the speed of the DC motor. Therefore, we can adjust the speed of the DC motor by adjusting the variable resistor knob according to your speed requirement.

What is best PWM frequency for DC motor?

As a rule of thumb, most small brushed DC motors will operate nicely with a PWM frequency of 50Hz to 100Hz and slow decay mode.

How do you control the speed of a DC motor?

Thus, the speed of a DC motor can control in three ways:

  1. By varying the flux, and by varying the current through field winding.
  2. By varying the armature voltage, and the armature resistance.
  3. Through the supply voltage.

What is DC motor speed control with a PIC microcontroller?

This tutorial is about dc motor speed control with a pic microcontroller using the PWM method. There are many applications of DC motors, where we need a variable speed of DC motor. For example, it has applications in electric cars, trucks, and aircraft. These are three examples where we need variable speed.

What is the PWM frequency of a PIC microcontroller?

Let’s see a C program for the PIC microcontroller where 2 switches controlling the speed of the DC motor. The oscillator frequency is 20 Mhz, PWM is 5.00kHz, Prescaler value is 4 and PR2 is 0xF9.

How to control the speed of the motor using PWM?

Two Push Button switches are provided to control the speed of the motor. Here we are using 12V DC Motor and average DC value delivered to motor can be varied by varying the duty ratio of the PWM. The average DC Voltage of 0% duty cycle is 0V, 25% duty cycle is 3V, 50% duty cycle is 6V, 75% duty cycle is 9V and for 100% duty cycle 12V.

What is the average DC voltage of the PIC microcontroller?

The average DC Voltage of 0% duty cycle is 0V, 25% duty cycle is 3V, 50% duty cycle is 6V, 75% duty cycle is 9V and for 100% duty cycle 12V. Note: VDD and VSS of the pic microcontroller is not shown in the circuit diagram.