A Digital AGC Design for Audio Chip

For an audio processing chip, ensuring that the power of the input signal is stable in a certain range can better play the performance of the chip, which requires the automatic gain control (AGC) algorithm to process the signal.The traditional analog AGC circuit has the problems of insufficient adjustment range and insufficient stability. The development of digital AGC has solved these problems, but it also has the problem of increasing environmental noise when processing small signals.This paper designs a kind of digital AGC feedback circuit for audio chip. The design uses the adjustable noise threshold circuit to distinguish the input signal first and then process the signal after it is confirmed to be effective, thus solving the problem of increasing the background noise when processing small signals to a large extent, and making the audio chip have better processing effect in different environments.