Hello friends, I hope you are doing well. In this tutorial, we will design the timing logic for a modified sine-wave inverter and study the original CD4047B and CD4017B approach. We will also develop an equivalent microcontroller timing example so you can see exactly how the positive, zero and negative intervals are produced. This article follows our tutorials on the basics of inverter topologies , the major inverter components and the pure sine-wave inverter . A modified waveform is simpler than filtered SPWM, but its harmonic content limits the loads that should use it. Figure: The comparison shows sinusoidal and stepped waveforms over a labeled 20 ms cycle. What Is a Modified Sine Wave? A modified sine wave is a stepped bipolar waveform. During each cycle, the inverter applies a positiv ...