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Hello everyone,welcome to my instructable! I hope you all are doing great. Recently, I got interested in experimenting with PWM signals and came across the concept of SPWM (or Sinusoidal Pulse Width Modulation)where the duty cycle of a train of pulses is being modulated by a sine wave. I came across a few results where such kind of SPWM signals can easily be created using a microcontroller where the duty cycle is being generated by using a lookup table that contains the necessary values to implement the sine wave.
I wanted to generate such SPWM signal without microcontroller and thus I used Operational Amplifiers as the heart of the system.
Lets get started!

LM324 Quad OpAmp IC
LM358 dual comparator IC
14 pin IC base/socket
10K resistors-2
1K resistors-2
4.7K resistors-2
2.2K resistors-2
2K variable resistor(preset)-2
0.1uF ceramic capacitor-1
0.01uF ceramic capacitor-1
5 pin male header
Veroboard or perfboard
Hot glue gun
Soldering equipments”

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