Patent ID: 7957544
Filing Date: 2011-06-07
Classification: H03F,H03G,H04R

Abstract:
1. A control apparatus for playing back audio by outputting an audio signal to a speaker, the control apparatus comprising: a generation unit configured to, before output of the audio signal, generate a pulse signal composed of a plurality of pulses, and output the generated pulse signal to a smoothing capacitor for the speaker; and a switch unit configured to switch between the audio signal and the pulse signal, wherein a duty ratio of each of the pulses is smaller the earlier the pulse exists on a time axis, and is larger the later the pulse exists on the time axis, wherein the generation unit includes: said control apparatus further comprising: a dividing unit configured to divide the digital value in each count cycle of the counter into a plurality of values, and output each of the values obtained by the dividing to the PWM circuit, wherein each of the pulses in the pulse signal has a duty ratio in accordance with a different one of the values obtained by the dividing in the count cycle of the counter.