Abstract: In order to output an analog signal from which unnecessary out-of-band noise components are appropriately removed in accordance with digital data to be reproduced, a reproduction frequency determination circuit and cutoff frequency selection circuit detect the frequency level of a reproduced signal associated with input digital data and switch an analog LPF to a filter of an appropriate cutoff frequency selected and determined based on the detection result, thereby appropriately removing unnecessary out-of-band noise components from an analog audio signal obtained from the digital data using the filter having the cutoff frequency according to the frequency level of a reproduced signal obtained by reproducing the digital data.

Abstract: A switching regulator circuit includes an inductor, a first condenser which provides a potential stored therein as a first output of the switching regulator circuit, a second condenser which provides a potential stored therein as a second output of the switching regulator circuit, and a switch set including a plurality of switches, the switch set establishing a first path, a second path, and a third path, the first path supplying energy from a DC power supply to the inductor for accumulation of the energy therein, the second path supplying the energy accumulated in the inductor to the first condenser, and the third path supplying the energy accumulated in the inductor to the second condenser.

Abstract: A switching regulator circuit includes an inductor, a first condenser which provides a potential stored therein as a first output of the switching regulator circuit, a second condenser which provides a potential stored therein as a second output of the switching regulator circuit, and a switch set including a plurality of switches, the switch set establishing a first path, a second path, and a third path, the first path supplying energy from a DC power supply to the inductor for accumulation of the energy therein, the second path supplying the energy accumulated in the inductor to the first condenser, and the third path supplying the energy accumulated in the inductor to the second condenser.

Abstract: In order to output an analog signal from which unnecessary out-of-band noise components are appropriately removed in accordance with digital data to be reproduced, a reproduction frequency determination circuit and cutoff frequency selection circuit detect the frequency level of a reproduced signal associated with input digital data and switch an analog LPF to a filter of an appropriate cutoff frequency selected and determined based on the detection result, thereby appropriately removing unnecessary out-of-band noise components from an analog audio signal obtained from the digital data using the filter having the cutoff frequency according to the frequency level of a reproduced signal obtained by reproducing the digital data.