Low frequency ac waveform generator
Abstract
Low frequency sine, cosine, triangle and square waves are synthesized in circuitry which allows variation in the waveform amplitude and frequency while exhibiting good stability and without requiring significant stabilization time. A triangle waveform is formed by a ramped integration process controlled by a saturation amplifier circuit which produces the necessary hysteresis for the triangle waveform. The output of the saturation circuit is tapped to produce the square waveform. The sine waveform is synthesized by taking the absolute value of the triangular waveform, raising this absolute value to a predetermined power, multiplying the raised absolute value of the triangle wave with the triangle wave itself and properly scaling the resultant waveform and subtracting it from the triangular waveform to a predetermined power and adding the squared waveform raised to the predetermined power with a dc reference and subtracting the squared waveform therefrom, with all waveforms properly scaled. The resultant waveform is then multiplied with a square wave in order to correct the polarity and produce the resultant cosine waveform.
 Publication:

Patent Application Department of Energy
 Pub Date:
 November 1983
 Bibcode:
 1983doe..reptV....B
 Keywords:

 Ac Generators;
 Design Analysis;
 Function Generators;
 Hysteresis;
 Low Frequencies;
 Waveforms;
 Amplitude Modulation;
 Correction;
 Frequency Modulation;
 Patent Applications;
 Ramp Functions;
 Sine Waves;
 Electronics and Electrical Engineering