Asahi Kasei Microdevices Corporation

Gunma University

Ibuki Mori

Haruo Kobayashi

Yoshihisa Yamada

Toshio Sugiyama

Masashi Kono

The invention provides a technique to widely spread the frequency spectrum of switching noise generated by a switching action and to reduce the noise level at a particular frequency. A switching regulator (A) includes a computing unit with computing function. First, in the computing unit, a pulse-width-modulation processing unit (PWM) () performs pulse-width-modulation processing of receiving a feedback signal corresponding to the output of a detectorto determine an on-duty cycle of a pulse signal. Subsequently, for the signal and data obtained by the PWM () to be subjected to further modulation processing for spectrum spreading, a branching processing is performed by making changing-over unit () randomly select asynchronous-modulation processing unit (ASM) () or pulse-position-modulation processing unit (PPM). When the PPM is selected, another branching processing is performed by making the changing-over unit () select a first PPM () or a second PPM () depending on the on-duty cycle.

Growing community of inventors

Tokyo, Japan

Ibuki Mori