Abstract: A PWM waveform generator generates the digitized waveform which may control an inverter so that the inverter output is pulse width modulated and generates a sine wave after filtering. A frequency controlling means includes a cycle clock cycling an address counter which addresses step data in a ROM, and the ROM data is fed to a PWM counter. This PWM counter has a clock input to reset a flip-flop and the output passes through a polarity switch to obtain the digitized waveform. This frequency controlling means is modified by an amplitude controlling means wherein the PWM counter is clocked at a variable frequency rate to control the width of the pulses directly proportional to the desired effective amplitude of the output waveform. The foregoing abstract is merely a resume of one general application, is not a complete discussion of all principles of operation or applications, and is not to be construed as a limitation on the scope of the claimed subject matter.