Controller for waveform synthesizer

A method and apparatus for producing a plurality of pulse width modulated control signals, the combination of which are pulsed representations of the pattern of a reference waveform, comprises a sine wave generating network for producing the reference sine wave, a triangular waveform generating network for producing a triangular wave, a plurality of level shifting circuits for level shifting the triangular wave to produce a plurality of triangular waves each at a different level and having a different range of amplitudes, and a plurality of comparators each for comparing an individual one of the plurality of level shifted triangular waves with each half-cycle of the reference sine wave, for producing the plurality of control signals. The control signals may be decoded by decoding networks, the decoded control signals being applied for operating a waveform synthesizer or inverter stage to produce a multitiered steplike notched waveform equivalent of the reference waveform.