Patent ID: 8129857

Claim:
A semiconductor circuit comprising: a first signal processing circuit that performs predetermined signal processing on a first signal to provide a change to a characteristic value thereof, and then outputs the signal as a second signal; a second signal processing circuit that performs predetermined signal processing on the second signal to provide a change to a characteristic value thereof, and then outputs the signal as a third signal; a first switching power supply that supplies a power supply voltage to the first signal processing circuit; and a second switching power supply that supplies a power supply voltage to the second signal processing circuit, wherein an amount of change provided to the characteristic value of the first signal by the first signal processing circuit, and an amount of change provided to the characteristic value of the second signal by the second signal processing circuit, are dependent on the respective power supply voltages, and wherein phases of the first switching power supply and the second switching power supply are set such that an error between the amount of change in the characteristic value of the first signal and its target value, and an error between that of the second signal and its target value, are to be canceled out by each other.