JPS647804A - Artificial waveform generating circuit - Google Patents

Abstract

PURPOSE:To obtain a waveform output of high accuracy by executing a shaping processing for making an inclination of an increase and a decrease different from a point where a waveform component has reached a specific value, to the waveform component for increasing and decreasing monotonously against a triangular wave, and showing an artificial sin wave and artificial cos wave. CONSTITUTION:The first triangular wave generating means (triangular wave generating circuit 4A) generates a triangular wave F, and adds a correction waveform G obtained by an adding means (waveform adding circuit 6), by which the upper limit reference voltage VrefH and the lower limit reference voltage VrefL are set to the maximum value and the minimum, value, respectively, and a triangular wave H is generated. The adding means derives a correction waveform section from triangular waves C, I generated by the second and the third triangular wave generating means, derives a correction waveform from the second triangular wave generating means in its section and adds it to the first triangular wave generating means. Subsequently, in accordance with the triangular wave obtained by the first triangular wave generating means, the triangular wave obtained by the third triangular wave generating means is added to a waveform shaping means, and to a waveform component for increasing and decreasing monotonously, a shaping processing for making an inclination of an increase and a decrease different from a point where its waveform component has reached a specific value, and a waveform output for showing an artificial sine wave and an artificial cosine wave is obtained. In such a way, waveform accuracy can be raised.