Direct Digital Synthesizers (DDS) are frequency synthesizers creating variable frequency arbitrary waveforms from a single, fixed-frequency reference clock. Many differents designs are used.

Direct Digital Synthesizer (DDS) is a type of frequency synthesizer used for creating arbitrary waveforms from a single, fixed-frequency reference clock. Applications of DDS include: signal generation, local oscillators in communication systems, function generators, mixers, modulators,[1] sound synthesizers and as part of a digital phase-locked loop.[2]

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