Microphone echo cancellation control circuit

Abstract

The utility model relates to the technical field of electronic circuits, and particularly discloses a microphone echo cancellation control circuit, which comprises a microphone audio input circuit, an echo cancellation circuit, a single chip microcomputer master control circuit and an audio amplification output circuit, the output end of the microphone audio input circuit is electrically connected with the input end of the echo cancellation circuit, and the output end of the single chip microcomputer master control circuit is electrically connected with the output end of the audio amplification output circuit. The output end of the echo cancellation circuit is electrically connected with the input end of the single-chip microcomputer main control circuit, and the output end of the single-chip microcomputer main control circuit is electrically connected with the audio amplification output circuit. According to the utility model, the echo elimination circuit is additionally arranged to eliminate echoes generated by sounds of both parties in digital talkback, so that audio signals without echo interference are obtained, the effect of eliminating field echoes is achieved, the conference quality is further improved, the normal proceeding of the conference is ensured, and the application range is wide.

Description

Technical Field

[0001] The utility model relates to the technical field of electronic circuits, and particularly relates to a microphone echo cancellation control circuit. Background Art

[0002] At present, existing microphones are divided into two types: wired and wireless. The most widely used is the wired microphone, which is simple and easy to use and meets the needs of general users. The current market trend has shifted towards wireless microphones with higher integration, which are not restricted by the application environment. Wireless microphones are mainly in the form of gooseneck, lapel, hand-held, etc., with a wide variety of types, greatly facilitating the daily work and life needs of people. During the process of voice communication with the remote end, especially during a conference with the remote end, when the microphone collects the audio signal, in addition to collecting the signal to be transmitted, it will inevitably collect some interference signals in the external environment, such as the echo of the external speaker, etc. That is, after one party speaks, the sound is played through the other party's speaker and then collected by the other party's microphone and sent back to oneself, resulting in an unsatisfactory conference effect and interfering with the normal progress of the conference. Content of the Utility Model

[0003] The technical problem to be solved by the utility model is to provide a microphone echo cancellation control circuit in view of the above-mentioned defects of the prior art. By adding an echo cancellation circuit to eliminate the echo generated by the voices of both parties in digital intercom, an audio signal without echo interference can be obtained, the effect of on-site echo is eliminated, the conference quality is further improved, the normal progress of the conference is ensured, and the applicable range is relatively wide.

[0004] In order to solve the above technical problem, the technical solution of the utility model is as follows:

[0005] A microphone echo cancellation control circuit includes a microphone audio input circuit, an echo cancellation circuit, a single-chip microcomputer main control circuit, and an audio amplification output circuit. The output end of the microphone audio input circuit is electrically connected to the input end of the echo cancellation circuit, the output end of the echo cancellation circuit is electrically connected to the input end of the single-chip microcomputer main control circuit, and the output end of the single-chip microcomputer main control circuit is electrically connected to the audio amplification output circuit.

[0006] Preferably, the single-chip microcomputer main control circuit includes a single-chip microcomputer chip U1, a program burning port P1, a crystal oscillator Y1, a capacitor C1, and a capacitor C2. The program burning port P1, the crystal oscillator Y1, the capacitor C1, and the capacitor C2 are all connected to the single-chip microcomputer chip U1.

[0007] Preferably, the echo cancellation circuit includes an echo cancellation chip U3, resistors R3, R4, R5, R6, R7, R8, R9, R10, R11, R12, R13, R14, R15, R16, capacitors C5, C6, C7, C8, C9, C10, C12, C13, C14, a triode Q1, diodes D1 and D2. The triode Q1 is respectively connected to the resistors R3, R4, R5, R6, R7, capacitor C5 and capacitor C6. The resistors R8 and R9 are respectively connected to the capacitor C5 and capacitor C6. The echo cancellation chip U3 is respectively connected to the resistors R8, R11, R12, R13, R14, capacitor C7, capacitor C8, capacitor C9, capacitor C12, diode D1 and diode D2. The resistors R9, capacitor C12, capacitor C13 and capacitor C14 are all connected to the resistor R16. The resistor R16 is connected to the single-chip microcomputer chip U1.

[0008] Preferably, the microphone audio output circuit includes a microphone MIC1, resistors R1, R2, capacitors C3 and C4. The resistors R1, R2 and capacitor C3 are all connected to the microphone MIC1. The capacitor C4 is respectively connected to the resistor R3 and the resistor R2.

[0009] Preferably, the audio amplification output circuit includes an audio amplifier U2 and an audio output interface P2. The audio amplifier U2 is respectively connected to the single-chip microcomputer chip U1 and the audio output interface P2.

[0010] Preferably, the echo cancellation chip U3 uses an echo cancellation ZL38040 device.

[0011] By adopting the above technical solution, a microphone echo cancellation control circuit provided by the utility model has the following beneficial effects: The output end of the microphone audio input circuit in the microphone echo cancellation control circuit is electrically connected to the input end of the echo cancellation circuit. The output end of the echo cancellation circuit is electrically connected to the input end of the single-chip microcomputer main control circuit. The output end of the single-chip microcomputer main control circuit is electrically connected to the audio amplification output circuit. The microphone audio input circuit accesses the original audio signal into the echo cancellation circuit. The echo cancellation circuit filters out the echo signal therein and then outputs it to the single-chip microcomputer main control circuit. Finally, it is amplified by the audio amplification output circuit and played. By adding an echo cancellation circuit to eliminate the echo generated by the voices of both parties in digital intercom, an audio signal without echo interference is obtained, the effect of on-site echo is eliminated, the meeting quality is further improved, the normal progress of the meeting is ensured, and the applicable range is relatively wide. Description of the Drawings

[0012] Figure 1 This is the circuit schematic diagram of the present utility model. Specific embodiments

[0013] The following further describes the specific embodiments of the present utility model in conjunction with the accompanying drawings. It should be noted here that the description of these embodiments is for helping to understand the present utility model, but does not constitute a limitation to the present utility model. In addition, the technical features involved in the various embodiments of the present utility model described below can be combined with each other as long as they do not conflict with each other.

[0014] In the description of the present utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation to the present utility model.

[0015] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of the present utility model, "a plurality" means at least two, such as two, three, etc., unless otherwise specifically and clearly defined.

[0016] As Figure 1 shown, in the circuit schematic diagram of the present utility model, the microphone echo cancellation control circuit includes a microphone audio input circuit, an echo cancellation circuit, a single-chip microcomputer main control circuit, and an audio amplification output circuit. The output end of the microphone audio input circuit is electrically connected to the input end of the echo cancellation circuit. The output end of the echo cancellation circuit is electrically connected to the input end of the single-chip microcomputer main control circuit. The output end of the single-chip microcomputer main control circuit is electrically connected to the audio amplification output circuit. It can be understood that in practical applications, the microphone audio input circuit, the echo cancellation circuit, the single-chip microcomputer main control circuit, and the audio amplification output circuit can all be integrated on a PCB circuit board and can be installed in various microphone and other power amplifier devices for use, and high-fidelity sound quality effects can be obtained, and the user experience effect is good.

[0017] Specifically, the single-chip microcomputer main control circuit includes a single-chip microcomputer chip U1, a program burning port P1, a crystal oscillator Y1, a capacitor C1, and a capacitor C2. The program burning port P1, the crystal oscillator Y1, the capacitor C1, and the capacitor C2 are all connected to the single-chip microcomputer chip U1. It can be understood that the single-chip microcomputer chip U1 uses an AT89C51 or STM32F103RBT6 chip, which serves as the control core of the entire circuit and centrally controls the working states of the above-mentioned echo cancellation circuit, single-chip microcomputer main control circuit, and audio amplification output circuit through signal transceiver and signal processing. Only the main circuit components and their connection relationships are listed above, and the remaining circuit components and their specific connection relationships are shown in the attached drawings, which will not be elaborated in this utility model.

[0018] Specifically, the echo cancellation circuit includes an echo cancellation chip U3, resistors R3, R4, R5, R6, R7, R8, R9, R10, R11, R12, R13, R14, R15, R16, capacitors C5, C6, C7, C8, C9, C10, C12, C13, C14, a triode Q1, a diode D1, and a diode D2. The triode Q1 is respectively connected to the resistors R3, R4, R5, R6, R7, the capacitor C5, and the capacitor C6. The resistors R8 and R9 are respectively connected to the capacitor C5 and the capacitor C6. The echo cancellation chip U3 is respectively connected to the resistors R8, R11, R12, R13, R14, the capacitors C7, C8, C9, C12, the diode D1, and the diode D2. The resistors R9, the capacitor C12, the capacitors C13, and the capacitor C14 are all connected to the resistor R16. The resistor R16 is connected to the single-chip microcomputer chip U1. It can be understood that the echo cancellation chip U3 can use an echo cancellation ZL38040 device, etc., for eliminating echo signals.

[0019] Specifically, the microphone audio output circuit includes a microphone MIC1, a resistor R1, a resistor R2, a capacitor C3, and a capacitor C4. The resistor R1, the resistor R2, and the capacitor C3 are all connected to the microphone MIC1, and the capacitor C4 is respectively connected to the resistor R3 and the resistor R2. The audio amplification output circuit includes an audio amplifier U2 and an audio output interface P2. The audio amplifier U2 is respectively connected to the single-chip microcomputer chip U1 and the audio output interface P2. It can be understood that the audio amplifier U2 uses a CAT5115 chip, which serves as a channel electronic volume controller and is controlled by two-wire serial data. The built-in reference circuit can form an electronic volume controller, and fewer peripheral circuits can be used. The volume ranges from 0 to 83 dB (1 dB per step), and each channel can be independently controlled. The audio signal is connected to the single-chip microcomputer chip U1 through the output terminal of the echo cancellation chip U3, and is amplified by the audio amplifier U2 and played by the external audio device connected thereto.

[0020] It can be understood that the design of the present utility model is reasonable and the structure is unique. By adding an echo cancellation circuit to eliminate the echo generated by the voices of both parties in digital intercom, an audio signal without echo interference can be obtained, the effect of on-site echo is eliminated, the meeting quality is further improved, the normal progress of the meeting is ensured, and the applicable range is relatively wide.

[0021] The embodiments of the present utility model have been described in detail above in conjunction with the accompanying drawings, but the present utility model is not limited to the described embodiments. For those skilled in the art, without departing from the principle and spirit of the present utility model, various changes, modifications, substitutions, and variations made to these embodiments still fall within the protection scope of the present utility model.

Claims

1. A microphone echo cancellation control circuit, characterized in that: It includes a microphone audio input circuit, an echo cancellation circuit, a single-chip main control circuit and an audio amplification output circuit. The output end of the microphone audio input circuit is electrically connected to the input end of the echo cancellation circuit, the output end of the echo cancellation circuit is electrically connected to the input end of the single-chip main control circuit, and the output end of the single-chip main control circuit is electrically connected to the audio amplification output circuit.

2. The microphone echo cancellation control circuit according to claim 1, characterized in that: The single-chip microcomputer main control circuit includes a single-chip microcomputer chip U1, a program burning port P1, a crystal oscillator Y1, a capacitor C1 and a capacitor C2. The program burning port P1, the crystal oscillator Y1, the capacitor C1 and the capacitor C2 are all connected to the single-chip microcomputer chip U1.

3. The microphone echo cancellation control circuit according to claim 2, characterized in that: The echo cancellation circuit includes an echo cancellation chip U3, a resistor R3, a resistor R4, a resistor R5, a resistor R6, a resistor R7, a resistor R8, a resistor R9, a resistor R10, a resistor R11, a resistor R12, a resistor R13, a resistor R14, a resistor R15, a resistor R16, a capacitor C5, a capacitor C6, a capacitor C7, a capacitor C8, a capacitor C9, a capacitor C10, a capacitor C12, a capacitor C13, a capacitor C14, a transistor Q1, a diode D1 and a diode D2. The transistor Q1 is connected to the resistor R3, the resistor R4, and the resistor R11 respectively. R5, resistor R6, resistor R7, capacitor C5 and capacitor C6 are connected, the resistor R8 and resistor R9 are connected to the capacitor C5 and capacitor C6 respectively, the echo cancellation chip U3 is connected to the resistor R8, resistor R11, resistor R12, resistor R13, resistor R14, capacitor C7, capacitor C8, capacitor C9, capacitor C12, diode D1 and diode D2 respectively, the resistor R9, capacitor C12, capacitor C13 and capacitor C14 are all connected to the resistor R16, and the resistor R16 is connected to the single-chip computer chip U1.

4. The microphone echo cancellation control circuit according to claim 2, characterized in that: The microphone audio output circuit includes a microphone MIC1, a resistor R1, a resistor R2, a capacitor C3 and a capacitor C4. The resistor R1, the resistor R2 and the capacitor C3 are all connected to the microphone MIC1, and the capacitor C4 is connected to the resistor R3 and the resistor R2 respectively.

5. The microphone echo cancellation control circuit according to claim 2, characterized in that: The audio amplification and output circuit includes an audio amplifier U2 and an audio output interface P2. The audio amplifier U2 is connected to the single-chip microcomputer chip U1 and the audio output interface P2 respectively.

6. The microphone echo cancellation control circuit according to claim 3, characterized in that: The echo cancellation chip U3 adopts the echo cancellation ZL38040 device.

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