Microphone howling suppression circuit in intercom system

Abstract

The invention discloses a microphone howling suppression circuit in an intercom system. The microphone howling suppression circuit comprises a first-stage voltage amplitude limiting circuit and a second-stage negative feedback gain automatic regulation alternating-current in-phase amplifying circuit, wherein the first-stage voltage amplitude limiting circuit comprises an input-stage coupling blocking capacitor, a reverse amplifying circuit, an output-stage coupling blocking capacitor and a diode series clamping circuit which are connected in sequence; the second-stage negative feedback gain automatic regulation alternating-current in-phase amplifying circuit comprises a positive-phase alternating-current amplifying circuit, and a negative feedback gain automatic regulation circuit, a coupling blocking capacitor and an alternating-current path amplification coupling capacitor which are connected with the positive-phase alternating-current amplifying circuit; and the first-stage voltage amplitude limiting circuit is connected with the second-stage negative feedback gain automatic regulation alternating-current in-phase amplifying circuit through a coupling capacitor, and the two stages of circuits are connected with a direct-current biasing circuit. Through adoption of the design, a voice signal can be prevented from being lost while noise is suppressed by the circuit, and the problem of howling caused by a microphone in an audio system is optimized and improved.

Description

technical field [0001] The invention relates to the technical field of an analog circuit for processing audio signals, in particular to a microphone howling suppression circuit for an intercom system. Background technique [0002] In the actual use of audio, the howling problem always affects the quality of audio. Generally, "howling" occurs when distortion is used, and it also occurs when delayed reverb is used. It is caused by the overload of the input signal, which is the first reason. And sometimes as long as you stand a little farther away from the speaker, the "howling" will disappear, and the distance from the speaker is too close, which is the second reason. The sound of "howling" is different when standing in different positions, and the angle between the speaker and the string is wrong, which is the third reason. Different timbres will have different "howling", and the frequency of the sound is wrong. This is the fourth reason. [0003] The howling caused by fee...

AI Technical Summary

Problems solved by technology

[0004] The object of the present invention is to overcome the shortcomings of the above-mentioned prior art, provide a microphone howling suppression circuit in the intercom system, ensure that the circuit suppresses the howling noise while the voice signal is not distorted, and optimize and improve the noise caused by the microphone in the audio system. howling problem

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