PWM DC Motor Speed Controller Using IC 555

Hey techies, welcome back to Techatronic. Are you searching for a DC motor speed controller circuit? If yes then read this article carefully and learn to make your own PWM DC motor speed controller circuit by using 555 timer IC. A 555 timer IC is used to obtain perfect delay signals. In this project, we are going to use a breadboard for making the circuit but if you want you can use a PCB board and solder the components. The detailed circuit is given below and we are also sharing the images of the circuit so it is easy to make. You can also check the cell phone signal jammer circuit using a 555 timer made by us. Also, check out more projects on basic electronics.

About the project

The circuit we made is useful for controlling the speed of a DC motor. It generates a PWM (pulse width modulation) signal continuously with different duty cycles so that the speed of the motor can vary. You can control the speed of the motor by rotating the potentiometer. Check out the LED flasher circuit made by us using 555 IC.

Components Required

  • 555 timer IC
  • Small connecting wires and a breadboard
  • Two 100 nF capacitors
  • 1K-ohm resistor
  • tip 122
  • DC motor and a 5-volts supply
  • Three in4007 diodes
  • 100K potentiometer

PWM dc motor speed controller Circuit Diagram

pwm dc motor speed controller

Place a 555 timer IC in the middle of the breadboard. Then connect the power supply to the positive and negative rails of the breadboard. Attach pin 1 of the IC to the negative rail and pin 8 to the positive rail of the breadboard. Place the tip-122 MOSFET and join its emitter pin to the positive rail and base pin with the positive leg of the diode. Attach the negative leg of the same diode with a pin of the DC motor. Connect another pin of the DC motor with the base pin of the tip-122 MOSFET. Take a 100K ohm potentiometer and connect its middle leg with the middle pin of the MOSFET. Join the positive leg of a diode with the negative leg of another diode and attach the node to the positive rail of the breadboard. Connect the negative leg of the first diode with the third pin of the potentiometer and the positive leg with the negative rail of the breadboard. Attach the first pin of the potentiometer with the negative rail and the third pin with pin number 3 of the 555 IC. Join a 100 nF capacitor between pin 5 and negative rail. Similarly between pin 1 and 2. Connect a 1K ohm resistor between pin 7 and positive rail. Join pins 2 and 6, 4 and 8 with each other as given in the diagram.

Final Look of the Project

Connect the positive and negative wires of the power supply to the breadboard and the PWM dc motor speed controller circuit is ready to use.

pwm dc motor speed controller

pwm dc motor speed controller

We hope that you understand the project completely and now try to make it once. While making this if you face any difficulties, feel free to use the comments section given below. You can also check tutorials on Arduino and Raspberry pi.