JPS5754436

PURPOSE:To obtain an output signal with high S/N, by storing a noise with a prescribed period to an analog memory and canceling the noise superimposed on a signal with a differential amplifier at signal read-in. CONSTITUTION:A noise waveform is inputted at no signal from an input terminal 1 and stored in an analog memory 6. The waveform superimposing signal and noise is inputted to a + input terminal of a differential amplifier 5 at signaling, and the noise waveform stored in the memory 6 is inputted to a - input terminal at the same time, and the amplifier 5 outputs the difference of both the waveforms as an output signal. As a result, the output signal of the amplifier 5 is a signal waveform rejected for noise components.