A semiconductor apparatus includes a signal source 7 that outputs a signal of predetermined frequency, a frequency divider 15 that receives the output signal of the signal source and is capable of switching the output signal to two or more frequency division ratios, a delta-sigma modulator 16 that controls the frequency division ratio of the frequency divider, and a bandpass filter 17 that receives an output of the frequency divider. The frequency of the input signal of the frequency divider is divided by the frequency division ratio controlled by the delta-sigma modulator, and quantization noise appearing in the output of the frequency divider generated by the delta-sigma modulator is attenuated with the bandpass filter. The semiconductor apparatus easily can convert a signal output by a single signal source to a signal of predetermined frequency and supply a plurality of signals of predetermined frequency using a simple configuration with reduced chip size.