A simple configured reducing noise peak DC-DC converter introducing delta-sigma modulation circuit

High frequency switching power converters are widely used because it can miniaturize equipments and it can convert electric power with high efficiency. And new fields of power supply use, such as mobile gear or medical equipments, are being developed. In these switching power converters, pulse width modulation (PWM) technique is widely used up to now. But in case of using PWM technique, noise peaks appear at the whole numbers of carrier frequency, and it is difficult to keep noise regulation. This paper proposes a DC-DC converter introducing delta-sigma modulator. The proposed circuit uses delta-sigma modulator, which can be realized by simple circuit, and the authors confirm the proposed circuit can reduce noise level.