Bluetooth microphone improvement circuit and Bluetooth microphone

Abstract

The utility model belongs to the technical field of microphones, and particularly relates to a Bluetooth microphone improvement circuit and a Bluetooth microphone, the Bluetooth microphone improvement circuit comprises a Bluetooth audio processing chip and an amplitude limiting circuit, the Bluetooth audio processing chip is connected with the amplitude limiting circuit, the amplitude limiting circuit is also connected with an electret MIC, and the Bluetooth audio processing chip is also connected with a Bluetooth antenna. By adding the amplitude limiting circuit, the signal amplitude of the Bluetooth audio processing chip is limited, signal overload is avoided, and tone quality distortion and noise are prevented.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the technical field of microphone, especially relates to a bluetooth microphone improvement circuit and bluetooth microphone. BACKGROUND

[0002] The bluetooth microphone usually refers to the bluetooth wireless microphone, is a kind of microphone using bluetooth technology to realize wireless audio transmission, is widely used in performance, lecture, meeting, video recording etc.

[0003] The existing bluetooth microphone is usually directly connected by integrated chip to electret MIC, and too large volume will cause serious distortion. UTILITY MODEL CONTENT

[0004] In view of the above problems, the utility model provides a bluetooth microphone improvement circuit and bluetooth microphone to solve the problems in the above background art.

[0005] To achieve the above object, the utility model provides the following technical scheme:

[0006] A bluetooth microphone improvement circuit, including bluetooth audio processing chip and limiting amplifier circuit, the bluetooth audio processing chip is connected with the limiting amplifier circuit, the limiting amplifier circuit is also connected with electret MIC, the bluetooth audio processing chip is also connected with bluetooth antenna.

[0007] Further, the limiting amplifier circuit includes capacitor CM3, capacitor CM4, capacitor CM5, resistance RM2, resistance RM3, diode D2, diode D3 and field effect transistor Q1, one end of capacitor CM3 is connected with MIC_0 pin of the bluetooth audio processing chip, the other end is connected with one end of resistance RM2, one end of capacitor CM4 and drain of field effect transistor Q1 respectively, the gate of field effect transistor Q1 is connected with one end of capacitor CM5, one end of resistance RM3 and cathode of diode D3 respectively, the other end of capacitor CM5 and resistance RM3 is grounded, the other end of capacitor CM4 is connected with cathode of diode D2 and anode of diode D3, the anode of diode D2 is grounded, one end of capacitor CM1 is connected with the other end of resistance RM2, the common end of capacitor CM1 and capacitor CM2 is connected with one end of resistance RM1, the electret MIC is connected, the other end of capacitor CM2 is grounded, and one end of resistance RM1 is connected with MIC_BIAS pin of the bluetooth audio processing chip.

[0008] Further, the model of the bluetooth audio processing chip is AC6976D.

[0009] Further, the bluetooth audio processing chip is also connected with switch.

[0010] Further, the power supply circuit is further included.

[0011] Further, the power supply circuit includes a TYPE-C interface and a charging chip UC2, and the TYPE-C interface is connected with the charging chip UC2.

[0012] The utility model discloses a bluetooth microphone, including the bluetooth microphone improvement circuit.

[0013] The utility model discloses a bluetooth microphone, including the bluetooth microphone improvement circuit.

[0014] The technical effects and advantages of the utility model will be described in the subsequent description, and part of them becomes obvious from the description, or is understood by implementing the utility model. The purposes and other advantages of the utility model can be realized and obtained through the structure indicated in the description and drawings. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical scheme in the embodiments of the utility model or the prior art, the following will briefly introduce the drawings needed to be used in the embodiment or the prior art description, and obviously, the drawings in the following description are some embodiments of the utility model, and for those skilled in the art, other drawings can also be obtained according to these drawings without creative labor.

[0016] Figure 1 The principle block diagram of the bluetooth microphone improvement circuit provided by the embodiment of the utility model is shown;

[0017] Figure 2 The circuit principle diagram of the limiting amplifier circuit provided by the embodiment of the utility model is shown;

[0018] Figure 3 The circuit principle diagram of the bluetooth audio processing chip provided by the embodiment of the utility model is shown;

[0019] Figure 4 The circuit principle diagram of the power supply circuit provided by the embodiment of the utility model is shown.

[0020] In the drawing:

[0021] 1-the bluetooth audio processing chip, 2-the limiting amplifier circuit. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme of the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some of the embodiments of the present application, but not all the embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0023] In the description of the present application, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application. In addition, in the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise explicitly and specifically limited.

[0024] Figure 1 A principle block diagram of the Bluetooth MIC improvement circuit provided by the embodiments of the present application is shown in FIG. 1, and a Bluetooth MIC improvement circuit is provided by the present application, which comprises a Bluetooth audio processing chip 1 and a limiting amplifier circuit 2. Figure 1 The Bluetooth audio processing chip 1 is connected with the limiting amplifier circuit 2, the limiting amplifier circuit 2 is further connected with an electret MIC, and the Bluetooth audio processing chip 1 is further connected with a Bluetooth antenna.

[0025] Figure 2 A circuit principle diagram of the limiting amplifier circuit 2 provided by the embodiments of the present application is shown in FIG. 2, and the limiting amplifier circuit 2 comprises a limiting amplifier 21 and a capacitor 22. Figure 2As shown, further, the limiting amplifier circuit 2 includes a capacitor CM3, a capacitor CM4, a capacitor CM5, a resistor RM2, a resistor RM3, a diode D2, a diode D3 and a field effect transistor Q1, one end of the capacitor CM3 is connected with the MIC_0 pin of the Bluetooth audio processing chip 1, the other end is connected with one end of the resistor RM2, one end of the capacitor CM4 and the drain of the field effect transistor Q1 respectively, the gate of the field effect transistor Q1 is connected with one end of the capacitor CM5, one end of the resistor RM3 and the cathode of the diode D3 respectively, the other end of the capacitor CM5 and the other end of the resistor RM3 are grounded, the other end of the capacitor CM4 is connected with the cathode of the diode D2 and the anode of the diode D3, the anode of the diode D2 is grounded, the other end of the resistor RM2 is connected with one end of the capacitor CM1, the common end of the capacitor CM1 and the capacitor CM2 is connected with one end of the resistor RM1, the MIC is connected, the other end of the capacitor CM2 is grounded, and one end of the resistor RM1 is connected with the MIC_BIAS pin of the Bluetooth audio processing chip 1.

[0026] The working principle of the limiting amplifier circuit 2 is as follows: the audio signal is input from the MIC_IN pin, transmitted to the main chip through the capacitor CM1, the resistor RM2 and the capacitor CM3; the capacitor CM4, the diode D2, the diode D3, the resistor RM3 and the capacitor CM5 form a voltage doubler rectifier circuit, rectify and filter the audio signal, and obtain a direct current voltage through the capacitor CM5; the voltage on the capacitor CM5 is given to the 1 pin of the field effect transistor Q1, so that the 3 pin of the field effect transistor Q1 has a current flowing to the 2 pin, thereby pulling down the audio signal and achieving the limiting function; the capacitor CM4 and the 3 pin of the field effect transistor Q1 are both connected with the signal of MIC2, so that the two circuits limit the voltage at the MIC2 point to a preset voltage value, about 0.3V, and the output voltage (CM5) of the voltage doubler rectifier cannot reach the voltage doubler value, so the MIC2 Q1 cannot have a high level and cannot be turned on.

[0027] Figure 3 The circuit principle diagram of the Bluetooth audio processing chip 1 is shown in the figure, Figure 3 Further, the model of the Bluetooth audio processing chip 1 is AC6976D. Optionally, the Bluetooth audio processing chip 1 is further connected with a switch.

[0028] Figure 4 The circuit principle diagram of the power supply circuit is shown in the figure, Figure 4 Further, the Bluetooth microphone improvement circuit provided by the utility model further includes a power supply circuit, and optionally, the power supply circuit includes a TYPE-C interface and a charging chip UC2, and the TYPE-C interface is connected with the charging chip UC2.

[0029] The utility model also provides a Bluetooth microphone, comprising the Bluetooth microphone improvement circuit.

[0030] In summary, the present invention limits the signal amplitude of the Bluetooth audio processing chip 1 by adding the limiting circuit 2, thereby avoiding signal overload and preventing sound quality distortion and noise.

[0031] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A Bluetooth microphone improvement circuit, characterized in that: It includes a Bluetooth audio processing chip and a limiting circuit. The Bluetooth audio processing chip is connected to the limiting circuit. The limiting circuit is also connected to an electret MIC. The Bluetooth audio processing chip is also connected to a Bluetooth antenna.

2. A Bluetooth microphone improvement circuit according to claim 1, characterized in that: The limiting circuit includes capacitor CM3, capacitor CM4, capacitor CM5, resistor RM2, resistor RM3, diode D2, diode D3 and field effect transistor Q1, one end of capacitor CM3 is connected to the MIC_0 pin of the Bluetooth audio processing chip, and the other end is respectively connected to one end of resistor RM2, one end of capacitor CM4 and the drain of field effect transistor Q1, the gate of field effect transistor Q1 is respectively connected to one end of capacitor CM5, one end of resistor RM3 and the cathode of diode D3, the other end of capacitor CM5 and the other end of resistor RM3 are grounded, the other end of capacitor CM4 is connected to the cathode of diode D2 and the anode of diode D3, the anode of diode D2 is grounded, the other end of resistor RM2 is connected to one end of capacitor CM1, the common end of capacitor CM1 and capacitor CM2 is connected to one end of resistor RM1, the electret MIC is connected, the other end of capacitor CM2 is grounded, and one end of resistor RM1 is connected to the MIC_BIAS pin of the Bluetooth audio processing chip.

3. The Bluetooth microphone improvement circuit according to claim 1, characterized in that: The model of the Bluetooth audio processing chip is AC6976D.

4. A Bluetooth microphone improvement circuit according to claim 1 or 3, characterized in that: The Bluetooth audio processing chip is also connected to a switch.

5. The Bluetooth microphone improvement circuit according to claim 1, characterized in that: Also includes power supply circuit.

6. The Bluetooth microphone improvement circuit according to claim 5, characterized in that: The power supply circuit includes a TYPE-C interface and a charging chip UC2, and the TYPE-C interface is connected to the charging chip UC2.

7. A Bluetooth microphone, characterized in that: The Bluetooth microphone improvement circuit comprises the Bluetooth microphone improvement circuit according to any one of claims 1 to 6.

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