WAVEFORM GENERATION CIRCUIT AND SPECTRUM SPREADING CLOCK GENERATION APPARATUS

摘要

PROBLEM TO BE SOLVED: To provide a spectrum spreading clock generation apparatus in which an effect of frequency spreading is improved approximately without increasing circuit costs by deforming a triangular wave used for frequency modulation with a simple method.

SOLUTION: In a modulation waveform generation circuit 10, its output signal includes a modulation waveform as illustrated in (a) with a real line. The modulation waveform is inputted to a voltage controlled oscillator (VCO) 11. In accordance with the modulation waveform, an oscillation frequency of the VCO 11 is modulated, and an output clock varying its frequency can be obtained as illustrated in (b). A frequency transit of the output clock is accompanied with a temporal change as illustrated in (c) by a real line.

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