AUTOMATIC LEVEL CONTROL CIRCUIT AND AUDIO DIGITAL SIGNAL PROCESSOR EMPLOYING THE SAME, ELECTRONIC EQUIPMENT

摘要

PROBLEM TO BE SOLVED: To provide an ALC (Automatic Level Control) circuit having desired input/output characteristics in a non-compressed domain and a compressed domain, respectively. SOLUTION: A variable gain amplifier 10 amplifies an input audio signal VI. A gain control section 11 controls a gain of the variable gain amplifier 10 in accordance with an amplitude of an output signal VO from the variable gain amplifier 10. A subtractor 17 subtracts the output signal VO of the variable gain amplifier 10 from the input audio signal VI. A sub amplifier 16 amplifies an output signal S1 of the subtractor 17. An adder 18 adds the output signal VO of the variable gain amplifier 10 and an output signal S2 of the sub amplifier 16. COPYRIGHT: (C)2011,JPO&INPIT