| 摘要 |
PROBLEM TO BE SOLVED: To provide a direct digital synthesizer(DDS) which outputs a digital/ analog converter with high accuracy so as to suppress production of an unnecessary spurious signal to the utmost. SOLUTION: The direct digital synthesizer reads an amplitude digital value 13 from a phase angle-amplitude conversion table 3 in response to phase angle data 12 obtained by sequentially adding a prescribed value synchronously with a clock 1 and outputs the amplitude digital value via a 1st digital/analog conversion means 5. More specifically, the direct digital synthesizer is provided with a storage means 6 that stores in advance a correction amount corresponding to the conversion distortion of the 1st digital/analog conversion means, a correction amount read means that reads the correction amount corresponding to the amplitude digital value from the storage means, and a 2nd digital/analog conversion means 8 so as to correct the conversion distortion of the 1st digital/ analog conversion means.
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