numerically controlled oscillator

A numerically controlled oscillator (NCO) or digitally controlled oscillator (DCO) is an electronic system for synthesizing a range of frequencies from a fixed timebase. The name is by analogy with "voltage-controlled oscillator".Note: the term "digitally controlled oscillator" has also been used to describe the combination of a voltage-controlled oscillator driven by a control signal from a digital-to-analog converter. This article is about the more recent design.
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