| 摘要 |
PROBLEM TO BE SOLVED: To miniaturize a sound signal switching means capable of preventing click noise from being generated in an audio apparatus and to make a time constant of a time constant section for switching control changeable, thereby more smoothly attaining switching. SOLUTION: A sound signal selection means 12 including a plurality of switches SW1a' to SW2b' each switching a sound signal into the other sound signal with an output level different from that of an original sound signal is provided between a sound input source and a sound output means. In the case of switching the sound signal into the other sound signal with an output level different from that of the original sound signal, the sound signals before and after the switching coexist and the sound signal is switched while they coexist. A SCF with a built-in IC configures the time constant section 8 for the switching control and the time constantτthereof is freely adjustably controlled by a clock signal Fclk resulting from the frequency-division of a reference signal generated from a VCO 6 at a variable frequency division rate. COPYRIGHT: (C)2006,JPO&NCIPI |
