Analog microphone mute circuit and audio device

Abstract

This utility model relates to an analog microphone mute circuit and audio device. The mute circuit includes: first and second connection terminals, a trigger switch unit, a voltage divider unit, an isolation filter unit, and two MOS switch units; the first and second connection terminals are respectively connected to the positive terminal of the audio output and the phantom power input, and the negative terminal of the audio output and the phantom power input; the trigger switch unit is turned on or off according to a mute trigger signal; the voltage divider unit generates a first voltage divider or a second voltage divider according to the on or off state of the trigger switch unit; one MOS switch unit is connected to the first connection terminal and the first terminal of the isolation filter unit; the other MOS switch unit is connected to the second connection terminal and the second terminal of the isolation filter unit; the control terminals of both MOS switch units are connected to the output terminal of the voltage divider unit, and are fully turned on when receiving the first voltage divider and slightly turned on when receiving the second voltage divider. Implementing this utility model can improve the isolation between the analog microphone input and output, and improve the user experience.

Description

Technical Field

[0001] This utility model relates to the field of audio technology, and more specifically, to an analog microphone mute circuit and audio device. Background Technology

[0002] In the field of conference systems, microphones are used at the front end for sound pickup. Microphones are divided into analog microphones and digital microphones. Although digital microphones have many processing functions, analog microphones are the first choice for some scenarios with extremely high requirements for sound quality and stability because of their advantages such as natural sound, stability, and real-time response.

[0003] In analog microphone applications, the main problem is insufficient isolation of the line switch, which easily leads to sound leakage. For example, when the microphone's mute switch is off, higher isolation reduces the likelihood of input signals (such as ambient noise or circuit noise) leaking to the output. In practical applications, even when the microphone is off, there is still an output signal due to ambient noise input, which affects the user experience.

[0004] Meanwhile, because analog microphones use phantom power, power-on / off operations generate transient circuit noise (such as a "clicking" sound), and there is a switching delay. This switching shock significantly impacts audio quality. In some analog microphones with GPIO control, the microphone also needs to be linked with other devices; power failure will cause synchronization failure. Therefore, the switching circuit of an analog microphone cannot be designed for conventional power-off. Currently, the most common design approach is to use isolation circuits to isolate the input and output of the audio line without complete power failure. However, in practical applications, the isolation level of current analog microphones is generally around 40dB, which is difficult to meet requirements and affects the user experience. Utility Model Content

[0005] The technical problem to be solved by this utility model is to provide an analog microphone mute circuit and audio device, which addresses the above-mentioned technical defects of the prior art.

[0006] The technical solution adopted by this utility model to solve its technical problem is as follows: constructing an analog microphone mute circuit, wherein the analog microphone includes a sound acquisition unit and an audio interface, the sound acquisition unit provides audio output and connects to phantom power input through the audio interface; the mute circuit includes: a first connection terminal, a second connection terminal, a trigger switch unit, a voltage divider unit, an isolation filter unit, and two MOS switch units;

[0007] The first connection terminal is used to connect the positive terminal of the audio output and the positive terminal of the phantom power input;

[0008] The second connection terminal is used to connect the negative terminal of the audio output and the negative terminal of the phantom power input;

[0009] The trigger switch unit is used to turn on when a mute trigger signal is received, and to turn off when the mute trigger signal is turned off;

[0010] The voltage divider unit is connected to the trigger switch unit, the first connection terminal and the second connection terminal, and is used to generate a first voltage divider at the output terminal of the voltage divider unit when the trigger switch unit is turned on, and to generate a second voltage divider when the trigger switch unit is turned off;

[0011] One of the MOS switching units has its first terminal connected to the first connection terminal and its second terminal connected to the first terminal of the isolation filter unit.

[0012] The first terminal of another MOS switching unit is connected to the second connection terminal, and the second terminal of the MOS switching unit is connected to the second terminal of the isolation filter unit.

[0013] Furthermore, the control terminals of the two MOS switching units are both connected to the output terminal of the voltage divider unit, and are fully turned on when receiving the first voltage divider and slightly turned on when receiving the second voltage divider.

[0014] Preferably, in the analog microphone mute circuit of this utility model, the trigger switch unit includes a first resistor, a first capacitor, a second resistor, and a first switching transistor;

[0015] The first end of the first resistor is used to receive the mute trigger signal. The second end of the first resistor is connected to the first end of the first capacitor and the first end of the second resistor. The second end of the second resistor is connected to the control terminal of the first switching transistor. The first end of the first switching transistor is connected to the first end of the voltage divider unit. The second end of the first switching transistor and the second end of the first capacitor are grounded.

[0016] Preferably, in the analog microphone mute circuit of this utility model, the voltage divider unit includes: a first voltage divider resistor, a second voltage divider resistor, a third voltage divider resistor, a fourth voltage divider resistor, a third resistor, and a second capacitor;

[0017] The first end of the first voltage divider resistor is connected to the first connection terminal, the first end of the second voltage divider resistor is connected to the second connection terminal, the second ends of the first voltage divider resistor and the second end of the second voltage divider resistor are connected to each other and simultaneously connected to the first end of the third voltage divider resistor, the first end of the fourth voltage divider resistor and the first end of the third resistor, and the second end of the third resistor is connected to the first end of the second capacitor and serves as the output terminal of the voltage divider unit;

[0018] The second end of the third voltage divider resistor is connected to the trigger switch unit as the first end of the voltage divider unit, and the second end of the fourth voltage divider resistor is grounded.

[0019] Preferably, in the analog microphone mute circuit of this utility model, the MOS switching unit includes a MOS transistor; the drain of the MOS transistor is the first terminal of the MOS switching unit, the source of the MOS transistor is the second terminal of the MOS switching unit, and the gate of the MOS transistor is the control terminal of the MOS switching unit.

[0020] Preferably, in the analog microphone mute circuit of this utility model, the isolation filter unit includes a third capacitor, the first end of the third capacitor is the first end of the isolation filter unit, and the second end of the third capacitor is the second end of the isolation filter unit.

[0021] Preferably, the analog microphone mute circuit of this utility model further includes a button unit and a trigger signal generation unit;

[0022] The button unit is used to generate a button signal according to the button operation, and the trigger signal generation unit is connected to the button unit to receive the button signal and generate the mute trigger signal.

[0023] Preferably, in the analog microphone mute circuit of this utility model, the trigger signal generation unit includes a D trigger chip, a fourth capacitor, a fourth resistor, a fifth resistor, and a sixth resistor;

[0024] The clock input pin of the D trigger chip is connected to the first end of the fourth resistor, the first end of the fifth resistor, and the first end of the fourth capacitor. The first end of the fourth resistor is connected to the button unit to receive the button signal. The second end of the fourth capacitor and the second end of the fifth resistor are grounded.

[0025] The data input pin and the logic negative output pin of the D trigger chip are connected to the first end of the sixth resistor, and the second end of the sixth resistor is used to output the mute trigger signal.

[0026] Preferably, the analog microphone mute circuit of this utility model further includes a mute indicator unit and an indicator switch unit; the trigger signal generation unit further includes a fifth capacitor and a seventh resistor; the logic positive output pin of the D trigger chip is connected to the first end of the seventh resistor;

[0027] The indicator light switch unit is connected to the second end of the seventh resistor and the first end of the fifth capacitor, so as to turn on or off according to the output of the logic positive output pin of the D trigger chip, and the second end of the fifth capacitor is grounded;

[0028] The silent indicator unit is connected to the indicator switch unit so that it is powered on when the indicator switch unit is turned on and powered off when the indicator switch unit is turned off.

[0029] Preferably, in the analog microphone mute circuit of this utility model, the indicator light switch unit includes a second switch tube, an eighth resistor, a ninth resistor, and a tenth resistor;

[0030] The first end of the eighth resistor is connected to the second end of the seventh resistor. The second end of the eighth resistor is connected to the control terminal of the second switch and the first end of the ninth resistor. The first end of the second switch and the second end of the ninth resistor are connected to a power supply voltage. The second end of the second switch is connected to the first end of the tenth resistor. The second end of the tenth resistor is used to connect to the mute indicator light.

[0031] This utility model also provides an audio device, including an analog microphone and an analog microphone mute circuit as described above.

[0032] The analog microphone mute circuit and audio device of this utility model have the following beneficial effects: they can improve the isolation between analog microphone input and output, and improve the user experience. Attached Figure Description

[0033] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings:

[0034] Figure 1 This is a schematic diagram of an embodiment of an analog microphone mute circuit according to the present invention;

[0035] Figure 2 This is a partial circuit diagram of an embodiment of an analog microphone mute circuit according to this utility model;

[0036] Figure 3 This is a partial circuit diagram of another embodiment of the analog microphone mute circuit of this utility model;

[0037] Figure 4 This is a schematic diagram of another embodiment of the analog microphone mute circuit of this utility model;

[0038] Figure 5 This is a partial circuit diagram of another embodiment of the analog microphone mute circuit of this utility model. Detailed Implementation

[0039] To provide a clearer understanding of the technical features, objectives, and effects of this utility model, the specific embodiments of this utility model will now be described in detail with reference to the accompanying drawings.

[0040] like Figure 1The diagram illustrates an embodiment of an analog microphone mute circuit according to the present invention. Figure 1 In one embodiment of the analog microphone mute circuit of the present invention, the analog microphone includes a sound acquisition unit 120 and an audio interface 110. The sound acquisition unit 120 provides audio output and connects to the phantom power input through the audio interface 110. The mute circuit 130 includes: a first connection terminal 131, a second connection terminal 132, a trigger switch unit 137, a voltage divider unit 136, an isolation filter unit 135, and two MOS switch units 134. The first connection terminal 131 is used to connect the positive terminal of the audio output and the positive terminal of the phantom power input; the second connection terminal 132 is used to connect the negative terminal of the audio output and the negative terminal of the phantom power input; the trigger switch unit 137 is used to be turned on when a mute trigger signal is received and turned off when the mute trigger signal is turned off; the voltage divider unit 136 connects to... The trigger switch unit 137, the first connection terminal 131, and the second connection terminal 132 are used to generate a first voltage divider at the output terminal of the voltage divider unit 136 when the trigger switch unit 137 is turned on, and to generate a second voltage divider when the trigger switch unit 137 is turned off; the first terminal of one of the MOS switch units 134 is connected to the first connection terminal 131 and the second terminal of the MOS switch unit 134 is connected to the first terminal of the isolation filter unit 135; the first terminal of the other MOS switch unit 134 is connected to the second connection terminal 132 and the second terminal of the MOS switch unit 134 is connected to the second terminal of the isolation filter unit 135; and the control terminals of both MOS switch units 134 are connected to the output terminal of the voltage divider unit 136, and are fully turned on when receiving the first voltage divider and slightly turned on when receiving the second voltage divider.

[0041] Specifically, the analog microphone, acting as an audio input device, generates audio through sound acquisition unit 120 during operation. This audio can be output via audio interface 110, for example, to audio playback device 210. Simultaneously, phantom power 220 provides phantom power input to the internal circuitry of the analog microphone via audio interface 110. In the mute circuit corresponding to the analog microphone, the positive terminal of the audio output and the positive terminal of the phantom power input are connected via first connection terminal 131, and the negative terminal of the audio output and the negative terminal of the phantom power input are connected via second connection terminal 132. The mute trigger switch unit 137 is turned on by a mute trigger signal, and turns off when the mute trigger signal is turned off. The mute trigger signal can be a level signal generated by circuit or software triggering. The voltage divider unit 136 forms a voltage divider circuit between the phantom power input and ground via first connection terminal 131 and second connection terminal 132, and the output of the voltage divider unit 136 provides a voltage divider output. The operating state of the voltage divider unit 136 is determined by the state of the trigger switch unit 137. When the trigger switch unit 137 is on, the voltage divider unit 136 outputs a first voltage; when the trigger switch unit 137 is off, the voltage divider unit 136 outputs a second voltage. Two MOS switch units 134 are symmetrically positioned on either side of the isolation filter unit 135 and are controlled by either the first or second voltage divider. When receiving the first voltage, both MOS switch units 134 enter a fully on state, at which point the first connection terminal 131 and the second connection terminal 132 are connected, canceling the phase of the audio output's positive and negative terminals, achieving a mute effect. The isolation filter unit 135 ensures isolation between the positive and negative terminals of the phantom power input, guaranteeing phantom power input. When the two MOS switching units 134 receive the second voltage divider, they both enter a fully micro-conducting state. At this time, the first connection terminal 131 and the second connection terminal 132 form an isolation relationship, isolating the positive and negative terminals of the audio output, allowing the microphone to output audio normally. The isolation filter unit 135 is used to ensure that the positive and negative terminals of the phantom power input are isolated, thus guaranteeing the phantom power input. Through this process, the original 40dB isolation can be increased to 72dB. Furthermore, the isolation filter unit 135 absorbs the instantaneous inrush current noise generated when the internal trigger switching unit is triggered, further improving the silencing effect.

[0042] In one embodiment, such as Figure 2 As shown, the sound acquisition unit 120 can be connected to a microphone via connector CON3. The microphone receives sound signals and generates audio output. The audio interface 110 can include connector CON1, meaning that audio output and phantom power input can be output or input via the pins of CON1.

[0043] In one embodiment, such as Figure 3 As shown, the trigger switch unit 137 includes a first resistor, a first capacitor, a second resistor, and a first switching transistor. The first terminal of the first resistor receives a mute trigger signal. The second terminal of the first resistor is connected to the first terminal of the first capacitor and the first terminal of the second resistor. The second terminal of the second resistor is connected to the control terminal of the first switching transistor. The first terminal of the first switching transistor is connected to the first terminal of the voltage divider unit 136. The second terminals of the first switching transistor and the second terminal of the first capacitor are grounded. Specifically, in... Figure 3 In the illustrated embodiment, the trigger switch unit 137 includes a first resistor R7, a second resistor R12, a first capacitor C4, and a first switching transistor Q4. A mute trigger signal (corresponding to the MUTE-A signal in the figure) is input to the base of transistor Q4 through a filter circuit formed by resistor R7, capacitor C4, and resistor R12, triggering transistor Q4 to conduct, thus grounding the first terminal of voltage divider unit 136. When transistor Q4 is turned off, the first terminal of voltage divider unit 136 is disconnected from ground. Ultimately, the trigger switch unit 137 triggers voltage divider unit 136 into two different states. In another embodiment, the first resistor, second resistor, and first capacitor can be formed by combining multiple devices. The first switching transistor can also be formed by combining one or more devices, and can also be a device with switching characteristics such as a MOSFET.

[0044] Optionally, the voltage divider unit 136 includes: a first voltage divider resistor, a second voltage divider resistor, a third voltage divider resistor, a fourth voltage divider resistor, a third resistor, and a second capacitor; the first end of the first voltage divider resistor is connected to the first connection terminal 131, the first end of the second voltage divider resistor is connected to the second connection terminal 132, the second ends of the first and second voltage divider resistors are interconnected and simultaneously connected to the first ends of the third, fourth, and third voltage dividers, the second end of the third resistor is connected to the first end of the second capacitor and serves as the output terminal of the voltage divider unit 136; the second end of the third voltage divider resistor serves as the first end of the voltage divider unit 136 and is connected to the trigger switch unit 137, and the second end of the fourth voltage divider resistor is grounded.

[0045] Specifically, such as Figure 3In the illustrated embodiment, in the voltage divider unit 136, the first voltage divider resistor may include resistor R1, the second voltage divider resistor may include resistor R3, the third voltage divider resistor may include resistor R9, the fourth voltage divider resistor may include resistor R8, the third resistor may include resistor R4, and the second capacitor may include capacitor C2. The phantom power input (via the circuit inputs identified by MIC+ and MIC-) forms a voltage divider at the first terminal of resistor R4 through resistors R1 and R3, and resistors R8 and R9, and provides this voltage divider output to the first MOS switching unit 134 and the second MOS switching unit 134 through the second terminal of resistor R4. It can be understood that the voltage divider unit 136 controls the second terminal of resistor R9 to be grounded or ungrounded to form the first voltage divider or the second voltage divider by triggering the switching unit 137. When the second terminal of resistor R9 is grounded, resistors R9 and R8 form a parallel relationship, thereby obtaining a parallel resistance value for voltage division, and the phantom power input forms the first voltage divider at the first terminal of resistor R4. When the second terminal of resistor R9 is not grounded, the voltage is divided through resistor R8, and the phantom power input forms a second voltage division at the first terminal of resistor R4.

[0046] In one embodiment, the MOS switching unit 134 includes a MOS transistor; the drain of the MOS transistor is the first terminal of the MOS switching unit 134, the source of the MOS transistor is the second terminal of the MOS switching unit 134, and the gate of the MOS transistor is the control terminal of the MOS switching unit 134. Specifically, both MOS switching units 134 are composed of MOS transistors. In one MOS transistor switching unit, a MOS transistor Q3 is included, the drain of MOS transistor Q3 is connected to the first connection terminal 131, the source of MOS transistor Q3 is connected to the first terminal of the isolation filter unit 135, and the gate of MOS transistor Q3 is connected to the output terminal of the voltage divider unit 136. In the other MOS transistor switching unit, a MOS transistor Q1 is included, the drain of MOS transistor Q1 is connected to the second connection terminal 132, the source of MOS transistor Q1 is connected to the second terminal of the isolation filter unit 135, and the gate of MOS transistor Q1 is connected to the output terminal of the voltage divider unit 136. MOS transistors Q3 and Q1 enter a fully on state and a slightly on state according to the input voltage of their gates. By adjusting the gate voltage of the two MOSFETs through the voltage divider unit 136, the conduction level of the MOSFETs is controlled, and the positive and negative audio signals are phase-cancelled, thereby achieving the effect of isolation and silencing. By optimizing the parameter configuration of this circuit and changing the circuit form, the original 40dB isolation can be increased to 72dB in practical applications, greatly improving the user experience.

[0047] In one embodiment, the isolation filtering unit 135 includes a third capacitor, with its first terminal and second terminal serving as the second terminal of the isolation filtering unit 135. Specifically, the third capacitor in the isolation filtering unit 135 may include a capacitor C14, which can absorb the instantaneous inrush current noise generated by circuits such as push-button switches, further improving the noise reduction effect.

[0048] like Figure 4 As shown, in one embodiment of the analog microphone mute circuit of this utility model, the mute circuit further includes a button unit 139 and a trigger signal generation unit 138. The button unit 139 is used to generate a button signal according to the button operation, and the trigger signal generation unit 138 is connected to the button unit 139 to receive the button signal and generate a mute trigger signal. That is, during the operation of the mute circuit, a button signal can be generated by the user's button operation on the button unit 139, and the button signal controls the trigger signal generation unit 138 to generate a mute trigger signal, which in turn controls the trigger switch unit 137 to perform the specific operation process. This process can be referred to the description above and will not be repeated here.

[0049] In one embodiment, such as Figure 5 As shown, the trigger signal generation unit 138 includes a D trigger chip, a fourth capacitor, a fourth resistor, a fifth resistor, and a sixth resistor. The clock input pin of the D trigger chip is connected to the first terminal of the fourth resistor, the first terminal of the fifth resistor, and the first terminal of the fourth capacitor. The first terminal of the fourth resistor is connected to the button unit 139 to receive button signals. The second terminals of the fourth capacitor and the second terminals of the fifth resistor are grounded. The data input pin and the logic negative output pin of the D trigger chip are connected to the first terminal of the sixth resistor. The second terminal of the sixth resistor is used to output a mute trigger signal. Specifically, in... Figure 5 In the illustrated embodiment, the trigger signal generation unit 138 includes a D trigger chip U4, a fourth capacitor C40, a fourth resistor R56, a fifth resistor R61, and a sixth resistor R81. The button signal generated by the button unit 139 is input to pin C1 of the D trigger chip U4 (corresponding to the clock input pin of the D trigger chip U4) via resistor R56. Pin Q1' (corresponding to the logic negative output pin of the D trigger chip U4) and pin D1 (corresponding to the data input pin of the D trigger chip) of the D trigger chip U4 output a mute trigger signal via resistor R81. The button signal is filtered by a filter circuit composed of capacitor C40 and resistor R61 before entering pin C1 of the D trigger chip U4. In one embodiment, the button unit 139 may include a button module (not shown) and connector J3. The button signal generated by the button module is input to the first end of resistor R56 via connector J3. The button can be a push-button switch.

[0050] like Figure 5 As shown, in one embodiment of the analog microphone mute circuit of this utility model, the mute circuit further includes a mute indicator unit (not shown in the figure) and an indicator switch unit 140; the trigger signal generation unit 138 further includes a fifth capacitor and a seventh resistor; the logic positive output pin of the D trigger chip is connected to the first end of the seventh resistor; the indicator switch unit is connected to the second end of the seventh resistor and the first end of the fifth capacitor, so as to turn on or off according to the output of the logic positive output pin of the D trigger chip, and the second end of the fifth capacitor is grounded; the mute indicator unit is connected to the indicator switch unit, so as to power on when the indicator switch unit is on and power off when the indicator switch unit is off. That is, in the mute circuit, the mute indicator unit can indicate the state of the mute circuit, which can also be understood as indicating the state of the analog microphone. The indicator switch unit powers on or off the mute indicator unit according to the output of the Q1 pin of the D trigger chip U4 (corresponding to the logic positive output pin of the D trigger chip). Among them, the seventh resistor includes resistor R64, and the fifth capacitor includes capacitor C3. The output of pin Q1 of the D trigger chip U4 is filtered by capacitor C3 and then input to the indicator light switch unit 140.

[0051] In one embodiment, the indicator light switch unit 140 includes a second switch transistor, an eighth resistor, a ninth resistor, and a tenth resistor; the first end of the eighth resistor is connected to the second end of the seventh resistor, the second end of the eighth resistor is connected to the control terminal of the second switch transistor and the first end of the ninth resistor, the first end of the second switch transistor and the second end of the ninth resistor are connected to a power supply voltage, the second end of the second switch transistor is connected to the first end of the tenth resistor, and the second end of the tenth resistor is used to connect to a mute indicator light.

[0052] Specifically, in the indicator light switch unit 140, the second switching transistor includes a transistor Q16, the eighth resistor includes a resistor R44, the ninth resistor includes a resistor R254, and the tenth resistor includes a resistor R5. The base of transistor Q16 is controlled by the output of pin Q1 of the D trigger chip U4, causing transistor Q16 to be turned on or off. When transistor Q16 is on, the supply voltage powers the mute indicator light through the conducting transistor Q16 and resistor R5. When transistor Q16 is off, the corresponding mute indicator light is powered off. Transistor Q16 can also be a switching transistor of the MOSFET type. In a specific embodiment, the mute indicator light unit may include a light board (not shown in the figure) and a connector CON2, with the light board connected to the indicator light switch unit via connector CON2.

[0053] Furthermore, the audio device provided by this utility model includes an analog microphone and the analog microphone mute circuit described above. The analog microphone is connected to an audio output device and a phantom power supply via an audio interface 110, providing audio output and phantom power input to the audio output device through the audio interface 110. The analog microphone mute circuit forms an indirect or direct connection with the audio interface 110 through a first connection terminal 131 and a second connection terminal 132, thereby further achieving mute of the analog microphone or maintaining normal audio output without affecting the phantom power input supplying power to the analog microphone. This mute circuit improves the isolation of the analog microphone when muted, ensuring the overall performance of the audio device.

[0054] It is understood that the above embodiments only illustrate preferred embodiments of the present utility model, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present utility model patent. It should be noted that for those skilled in the art, the above technical features can be freely combined, and several modifications and improvements can be made without departing from the concept of the present utility model, all of which fall within the protection scope of the present utility model. Therefore, all equivalent transformations and modifications made within the scope of the claims of the present utility model should fall within the coverage of the claims of the present utility model.

Claims

1. An analog microphone muting circuit, comprising: The analog microphone includes a sound acquisition unit and an audio interface. The sound acquisition unit provides audio output and connects to phantom power input through the audio interface. The mute circuit includes: a first connection terminal, a second connection terminal, a trigger switch unit, a voltage divider unit, an isolation filter unit, and two MOS switch units. The first connection terminal is used to connect the positive terminal of the audio output and the positive terminal of the phantom power input; The second connection terminal is used to connect the negative terminal of the audio output and the negative terminal of the phantom power input; The trigger switch unit is used to turn on when a mute trigger signal is received, and to turn off when the mute trigger signal is turned off; The voltage divider unit is connected to the trigger switch unit, the first connection terminal and the second connection terminal, and is used to generate a first voltage divider at the output terminal of the voltage divider unit when the trigger switch unit is turned on, and to generate a second voltage divider when the trigger switch unit is turned off; One of the MOS switching units has its first terminal connected to the first connection terminal and its second terminal connected to the first terminal of the isolation filter unit. The first terminal of another MOS switching unit is connected to the second connection terminal, and the second terminal of the MOS switching unit is connected to the second terminal of the isolation filter unit. Furthermore, the control terminals of the two MOS switching units are both connected to the output terminal of the voltage divider unit, and are fully turned on when receiving the first voltage divider and slightly turned on when receiving the second voltage divider.

2. The analog microphone muting circuit of claim 1, wherein, The trigger switch unit includes a first resistor, a first capacitor, a second resistor, and a first switching transistor; The first end of the first resistor is used to receive the mute trigger signal. The second end of the first resistor is connected to the first end of the first capacitor and the first end of the second resistor. The second end of the second resistor is connected to the control terminal of the first switching transistor. The first end of the first switching transistor is connected to the first end of the voltage divider unit. The second end of the first switching transistor and the second end of the first capacitor are grounded.

3. The analog microphone muting circuit of claim 1, wherein, The voltage divider unit includes: a first voltage divider resistor, a second voltage divider resistor, a third voltage divider resistor, a fourth voltage divider resistor, a third resistor, and a second capacitor; The first end of the first voltage divider resistor is connected to the first connection terminal, the first end of the second voltage divider resistor is connected to the second connection terminal, the second ends of the first voltage divider resistor and the second end of the second voltage divider resistor are connected to each other and simultaneously connected to the first end of the third voltage divider resistor, the first end of the fourth voltage divider resistor and the first end of the third resistor, and the second end of the third resistor is connected to the first end of the second capacitor and serves as the output terminal of the voltage divider unit; The second end of the third voltage divider resistor is connected to the trigger switch unit as the first end of the voltage divider unit, and the second end of the fourth voltage divider resistor is grounded.

4. The analog microphone mute circuit according to claim 1, characterized in that, The MOS switching unit includes a MOS transistor; the drain of the MOS transistor is the first terminal of the MOS switching unit, the source of the MOS transistor is the second terminal of the MOS switching unit, and the gate of the MOS transistor is the control terminal of the MOS switching unit.

5. The analog microphone muting circuit of claim 1, wherein, The isolation filter unit includes a third capacitor, the first end of which is the first end of the isolation filter unit, and the second end of which is the second end of the isolation filter unit.

6. The analog microphone muting circuit of claim 1, wherein, It also includes a button unit and a trigger signal generation unit; The button unit is used to generate a button signal according to the button operation, and the trigger signal generation unit is connected to the button unit to receive the button signal and generate the mute trigger signal.

7. The analog microphone muting circuit of claim 6, wherein, The trigger signal generation unit includes a D trigger chip, a fourth capacitor, a fourth resistor, a fifth resistor, and a sixth resistor; The clock input pin of the D trigger chip is connected to the first end of the fourth resistor, the first end of the fifth resistor, and the first end of the fourth capacitor. The first end of the fourth resistor is connected to the button unit to receive the button signal. The second end of the fourth capacitor and the second end of the fifth resistor are grounded. The data input pin and the logic negative output pin of the D trigger chip are connected to the first end of the sixth resistor, and the second end of the sixth resistor is used to output the mute trigger signal.

8. The analog microphone muting circuit of claim 7, wherein, It also includes a mute indicator unit and an indicator switch unit; the trigger signal generation unit further includes a fifth capacitor and a seventh resistor; the logic positive output pin of the D trigger chip is connected to the first end of the seventh resistor; The indicator light switch unit is connected to the second end of the seventh resistor and the first end of the fifth capacitor, so as to turn on or off according to the output of the logic positive output pin of the D trigger chip, and the second end of the fifth capacitor is grounded; The silent indicator unit is connected to the indicator switch unit so that it is powered on when the indicator switch unit is turned on and powered off when the indicator switch unit is turned off.

9. The analog microphone muting circuit of claim 8, wherein, The indicator light switch unit includes a second switch transistor, an eighth resistor, a ninth resistor, and a tenth resistor; The first end of the eighth resistor is connected to the second end of the seventh resistor. The second end of the eighth resistor is connected to the control terminal of the second switch and the first end of the ninth resistor. The first end of the second switch and the second end of the ninth resistor are connected to a power supply voltage. The second end of the second switch is connected to the first end of the tenth resistor. The second end of the tenth resistor is used to connect to the mute indicator light.

10. An audio device, comprising: Includes an analog microphone, and an analog microphone mute circuit as described in any one of claims 1 to 9.

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