Patent ID: 6839676

Claim:
An audio-decoder apparatus for decoding encoded audio signals, comprising: a circuit substrate, for use in one of a 2-channel model audio device and a 5.1-channel model audio device, said circuit substrate having a first portion common to use in both said 2-channel model audio device and said 5.1 channel model audio device, and a second portion, only in said 5.1-channel model audio device, for use together with said first portion, said first portion of said circuit substrate comprising: a decoder, for decoding an audio signal input to said decoder, said decoder having a plurality of output terminals, each said output terminal comprising at least one signal line, and one selected from the group consisting of: at least one digital-to-analog (D/A) converter with a built-in phase-locked-loop (PLL), and at least one a D/A converter having a clock signal generation function, capable of being connected to said decoder over at least one signal line, and at least one connection for at least one D/A converter without a built-in PLL, each said at least one connection comprising at least one signal line to an input terminal of said D/A converter without a built-in PLL, such that said at least one signal line is capable of being connected to said decoder; and a switching means, for enabling arbitrary switching of a connection mode over said respective signal lines, for a preselected, fixed one of said 2-channel model audio device and said 5.1-channel model audio device, between one of said output terminals of said decoder, and a said input terminal of one of said D/A converters of said circuit substrate.