| 摘要 |
PURPOSE:To minimize the influence of the converting error of an A/D conversion and to prevent the deterioration of S/N providing a means to attenuate to an A/D converted digital signal to the value in which the digital signal processing means is not overflown at the input side of a digital signal processing means. CONSTITUTION:The analog signal of a processing object is converted to a digital signal with an A/D converter 10. The digital signal is inputted through a signal line 11 equivalent to a digital signal supplying means to an attenuator 18 equivalent to a digital signal attenuating means and attenuated in a prescribed quantity digital way. After a prescribed digital signal processing is executed by a digital signal processing part 12 equivalent to the digital signal processing means, the attenuated digital signal is converted to an analog signal by a D/A converter 14 equivalent to a D/A converting means. The analog signal is outputted through an amplifier 19 equivalent to an analog amplifying means. Thus, the overflowing is prevented and the clip of an output waveform can be prevented. |
