Patent ID: 8278998

Claim:
A power supply noise reduction circuit for reducing noise generated in a power supply, said power supply noise reduction circuit comprising: said power supply; a resonance circuit, providing a means for resonating a noise in said power supply for setting a frequency of the noise equal or close to a resonance frequency; and a filter, providing a means for attenuating the power supply noise and being set equal to close to the resonance frequency, wherein said resonance circuit comprises a parallel resonance circuit, and said resonance circuit and said filter are connected in series with said power supply, said parallel resonance circuit and said filter being tuned to frequencies related in a predetermined manner to a predetermined clock frequency, and said noise being reduced comprises a noise generated in said power supply, as caused by a switching at said predetermined clock frequency, and said noise is reduced by said resonance circuit shifting an energy of said noise to a different frequency and said filter then attenuating said shifted energy.