Delta-sigma modulation apparatus and signal amplification apparatus

摘要

The present invention is directed to a signal amplifier apparatus adapted for carrying out delta-sigma modulation of an input signal to carry out pulse width modulation of that signal S1 to obtain PWM signal S2 to amplify this PWM signal S2 by an amplifier so that a signal S3 of a predetermined magnitude is provided, wherein the signal amplifier apparatus comprises a correction circuit (104) for correcting output of a quantizer (103) provided at a delta-sigma modulation device (10), and the correction circuit (104) is installed (provided) at feedback path with respect to the input side from the quantizer (103) or immediately before a pulse width modulator (11) to thereby correct distortion taking place at the amplifier. In addition, the signal amplifier apparatus according to the present invention compares PWM signals at input and output of the amplifier to correct output of the quantizer (103) provided at the delta-sigma modulation device (10) so as to cancel distortion quantity taking place at the amplifier in accordance with respective rising time difference and falling time difference to thereby correct distortion taking place at the amplifier.