Earphone for eliminating noise and drive circuit thereof

Abstract

The invention relates to an earphone for eliminating noise and a drive circuit thereof. The drive circuit integrates an ANC (Active Noise Cancellation) module, an audio head amplifier, a mixer and a BTL (Bridge Tied Load) audio amplifier into a chip through an SOC (System On Chip) technology. By implementing the technical scheme of the invention, due to the adoption of the SOC technology, the invention has the advantages of avoiding introducing a new noise signal, avoiding signal attenuation and distortion, simplifying the simulation of wiring of the ANC module and enabling the quantity of connecting lines of a left auricle chamber and a right auricle chamber, reducing external assemblies, correspondingly lowering the cost, arranging an SOC circuit with an ANC function in the auricle chambers in the earphone having an application design of avoiding noise disturbance of time division multiple access in wireless communication radio wave.

Description

technical field [0001] The invention relates to the field of audio equipment, more specifically, an earphone with an active noise cancellation function and a driving circuit thereof. Background technique [0002] The market for portable electronic devices has grown since the days of the cassette player. One of the growing areas of portable electronic devices is noise cancellation technology, which is used to reduce the amplitude of noise sound waves reaching the user's eardrums. Active Noise Cancellation technique (ANC) technology uses electronic means to generate sound waves with the same amplitude as the input ambient noise but with a phase difference of 180 degrees, so the ambient noise is eliminated due to destructive interference. [0003] Due to the increasing number of portable audio devices such as MP3, mobile phones, iPod, etc., the requirements for ANC technology are constantly increasing. This demand drives the development of ANC technology towards low cost, sma...

AI Technical Summary

Problems solved by technology

[0007] 1. The line from the microphone to the ANC device is too long, which may introduce new noise signals;

[0008] 2. If the line from the audio amplifier in the control unit to the speaker is too long, the signal will be attenuated and distorted;

[0009] 3. The wiring between the control components and the earbuds with speakers and microphones is complicated;

[0010] 4. The discrete and DSP ANC devices are too large to be placed in the ear chamber;

[0011] 5. Discrete and DSP ANC devices require a large number of external components, resulting in too many pins and high cost;

[0012] 6. The ANC device of DSP needs software integration;

[0013] 7. DSP and discrete ANC devices have high energy consumption and are prone to high-frequency interference;

[0014] 8. Discrete and DSP ANC devices are not conducive to mass production

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