AUDIO POWER AMPLIFIER IC AND AUDIO SYSTEM WITH THE SAME

摘要

PPROBLEM TO BE SOLVED: To provide an audio power amplifier IC capable of suppressing reduction of sound quality in an audio system employing a plurality of audio power amplifier ICs. PSOLUTION: An audio power amplifier IC 1 of the present invention comprises: a clock generating circuit 10 for generating an internal generation clock; a clock terminal CLK from which the internal generation clock is outputted or to which an external clock is inputted; a clock selecting circuit 11 which selects one of the internal generation clock and the external clock as a reference clock BCLK; an audio signal input terminal IN1 to which an audio signal is inputted; and a digital power amplifier circuit 51 including a pulse modulating circuit 61 which outputs a pulse generated based on the reference clock BCLK in accordance with a voltage of the inputted audio signal, and an output circuit 71 which receives input of the pulse outputted from the pulse modulating circuit 61 and outputs the pulse with low output impedance. PCOPYRIGHT: (C)2009,JPO&INPIT