| 摘要 |
AΔΣmodulation digital-analogue converter of the present invention includes: a look-up table in which a correspondence relationship between each of a plurality of possible input values of an input signal externally supplied, and each of compensation values individually associated with the possible input values, are stored; and a nonlinear compensation circuit (6) for compensating the input signal externally supplied, based on a compensation value associated with the input signal among the compensation values, and supplying aΔΣmodulation section (1) the input signal thus compensated. A sine wave is used as the input signal. The compensation value is set based on magnitudes of a spectrum of odd-order harmonics whose frequencies are A times more than a frequency of the sine wave (A is an odd number), the spectrum obtained in such a manner that an output of a D-Class amplifier (2) or an output of theΔΣmodulation digital-analogue converter is subjected to a frequency analysis without a compensation with respect to the sine wave by the nonlinear compensation circuit (6). Therefore, it is possible to provide aΔΣmodulation digital-analogue converter which (i) suppresses generation of odd-order harmonics with a simple circuit arrangement, and therefore (ii) is excellent in SNR and THD+N.
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