Digital automatic gain control linearizer and digital automatic gain control circuit using the same

摘要

A digital automatic gain control linearizer for controlling a variable gain control element for automatically controlling gain, using an analog signal obtained by converting input digital data includes a memory an average calculation unit. The memory outputs upper and lower limit data corresponding respectively to the upper and lower limits of a binary data range which can be expressed by a plurality of upper bits forming the digital data. The average calculation unit calculates the average of one and other data of the upper and lower limit data, and repeats average calculation a predetermined number of times using the calculated average at least one of the upper limit data and the lower limit data. Average calculation is repeated a number of times corresponding to the lower-bit value of the digital data except for the plurality of upper bits, and the variable gain control element is controlled in accordance with the average calculated by the average calculation unit.