摘要 |
An amplitude control device for controlling an amplitude of a data signal having an reference amplitude includes an A/D converter which converts the data signal to an n-bit digital signal, an extraction circuit for extracting the reference amplitude from the n-bit digital signal, a compactor for comparing the extracted reference amplitude with a predetermined amplitude to produce a first signal when the extracted reference amplitude is greater than the predetermined amplitude, and a second signal when the extracted reference amplitude is smaller than the predetermined amplitude. A counter counts up and down on receipt of the first signal and second signal, respectively, and produces an m-bit digital signal representing the counting result. A ROM stores a table in which the n-bit digital signal and the m-bit digital signal are used as an address for designating a value equal to the n-bit digital signal multiplied by a coefficient determined by the m-bit digital signal.
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