Abstract: A digital/analog conversion apparatus to convert a digital signal into an analog signal. The digital/analog conversion apparatus can generate a high-quality analog signal, even when elements configuring the digital/analog conversion apparatus have variance, with high resolution and a small circuit size. The data conversion apparatus is provided with a first data converter to reduce the number of bits of an input signal, a second data converter to convert the format of the first output signal, and a third data converter for conversion into a code which corresponds to the history of the output from the second data converter.

Abstract: A digital sound system suitable for a digital speaker device to directly convert analog sound by a circuit using a ?? modulator and a mismatch shaping filter circuit to output a plurality of digital signals and a plurality of speakers driven by the plurality of digital signals. A digital speaker driving device includes a ?? modulator, a post filter, s driving circuits, and a power supply circuit to supply power to the ?? modulator, the post filter and the s driving elements, and the s driving circuits are adapted to s digital signal terminals.