AUTOMATIC GAIN CONTROL CIRCUIT, GAIN CONTROL METHOD OF AMPLIFIER, DETECTION METHOD OF LOCKED STATE OF AMPLIFIER IN AUTOMATIC GAIN CONTROL LOOP

摘要

PROBLEM TO BE SOLVED: To provide an automatic gain control (AGC) approach suitable for controlling an amplifier and producing a signal indicating that the AGC is in its optimal state.;SOLUTION: A method, algorithm, circuits and/or systems for automatic gain control (AGC), are disclosed. In one embodiment, an AGC circuit includes: a comparator configured to compare an output of an amplifier against a reference voltage; a gain logic configured to decrease a gain of the amplifier when an output of the comparator has a first state, and to periodically increase the gain of the amplifier; a digital-to-analog converter (DAC) configured to receive an output from the gain logic and control the gain of the amplifier; and a lock detection logic configured to determine, from the output of the gain logic, the time when the gain of the amplifier is in a predetermined range.;COPYRIGHT: (C)2009,JPO&INPIT