Generate A PWM Signal using 555 Timer IC & A Potentiometer

Published at : 23 Dec 2025

In this video we’ll be generating a PWM signal using a 555 timer. I have a 555 timer here generating a square wave signal that I can control using a potentiometer to replicate a pulse width modulated signal. You can see as I change the value of this pot, the signal is changing from mostly off to mostly on and vice versa, and the led is getting brighter and dimmer. If you have no experience with the 555 timer, watch my last video, I went into a fair bit of detail of how it all works. This video will build off the back of that one.

Link to 555 Timers: https://amzn.to/3qFTWyZ

Previous Video: https://youtu.be/RnMBxAfGnQo

Timestamps
0:00 Intro
1:00 What is PWM?
4:19 Basic 555 Timer Schematic
5:05 Output Voltage & Capacitor Voltage
8:30 Replacing R2
10:25 Potentiometer Explanation
16:15 Charging Paths
17:30 Schematic
21:05 Demonstration
23:45 Buzzer
_____________

Hi, I'm Hamed, an Electrical & Electronics Engineering Student in Leeds, UK. At the time of recording this video I am approaching my third and final year at university.

Visit my website at www.hamed.engineer

If you have any questions you can email me at hamed@hamed.engineer or just comment below.

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