Analog microphone open-mic detection device

Abstract

The application discloses a kind of analog microphone open microphone detection device, including analog microphone interface, signal amplification module, rectifier module and phantom power module, the first end of analog microphone interface is connected phantom analog microphone, the second end of analog microphone interface is connected with the input end of signal amplification module, the output end of signal amplification module is connected with the input end of rectifier module, signal amplification module is amplified for phantom analog microphone microvoltage signal generated in response to environmental noise, the output end of rectifier module is connected with the host chip of digital conference host, rectifier module is rectified for the electric signal output by signal amplification module, the input end of phantom power module is connected with digital conference host, the output end of phantom power module is connected with the second end of analog microphone interface, whether phantom analog microphone can be detected open microphone, phantom analog microphone is managed on-line is realized.

Description

Technical Field

[0001] This invention relates to the field of audio equipment technology, and in particular to a device for detecting the liveness of an analog microphone. Background Technology

[0002] Current digital conferencing systems use matching conferencing hosts and microphones, and are generally not compatible with phantom analog microphones.

[0003] Normally, phantom microphones are directly connected to a mixing console or analog amplifier (with phantom power) for audio amplification. However, the mixing console or analog amplifier with phantom power doesn't display the number of phantom microphones connected, making microphone management inconvenient for conference administrators. When a digital conference system's main unit connects to external phantom microphones, it cannot detect whether the external microphone is on.

[0004] When a digital conference host connects to a conference microphone, the host can detect each microphone and display the number of microphones. However, if a virtual analog microphone is directly connected to the digital conference system, it generally cannot detect whether the analog microphone is online in the digital conference system. Summary of the Invention

[0005] This invention provides a phantom microphone activation detection device, which can detect whether a phantom microphone is activated, enabling the digital conference host to manage the phantom microphone.

[0006] The analog microphone open detection device provided by this invention includes:

[0007] An analog microphone interface, wherein the first end of the analog microphone interface is connected to a phantom analog microphone, and the second end of the analog microphone interface is connected to the input end of a signal amplification module;

[0008] A signal amplification module, the output of which is connected to the input of a rectifier module, is used to amplify the micro-voltage signal generated by the phantom microphone in response to ambient noise.

[0009] A rectifier module, the output of which is connected to the main control chip of the digital conference host, is used to rectify the electrical signal output by the signal amplification module;

[0010] The phantom power module has its input connected to the digital conference host and its output connected to the second end of the analog microphone interface.

[0011] Optionally, the analog microphone activation detection device further includes a signal preprocessing module, the input of which is connected to the second end of the analog microphone interface, and the output of which is connected to the sound card of the digital conference host.

[0012] Optionally, the signal amplification module includes a first-stage operational amplifier unit and a second-stage operational amplifier unit. The input terminal of the first-stage operational amplifier unit is connected to the second terminal of the analog microphone interface, the output terminal of the first-stage operational amplifier unit is connected to the input terminal of the second-stage operational amplifier unit, and the output terminal of the second-stage operational amplifier unit is connected to the input terminal of the rectifier module.

[0013] Optionally, the first-stage operational amplifier unit includes a first operational amplifier, a power supply circuit, a first input circuit, and a first feedback circuit;

[0014] The input terminal of the power supply circuit is connected to the reference power supply, and the output terminal of the power supply circuit is connected to the non-inverting input terminal of the first operational amplifier.

[0015] The input terminal of the first input circuit is connected to the second terminal of the analog microphone interface, and the output terminal of the first input circuit is connected to the non-inverting input terminal of the first operational amplifier.

[0016] The first terminal of the first feedback circuit is grounded, and the second terminal of the first feedback circuit is connected to the output terminal of the first operational amplifier.

[0017] The output terminal of the first operational amplifier is connected to the input terminal of the second operational amplifier unit.

[0018] Optionally, the power supply circuit includes resistors R20, R18, and R25, and capacitors C21 and C24.

[0019] The first end of resistor R20 is connected to the reference power supply. The second end of resistor R20 is connected to the first ends of resistors R18, R25, capacitors C21 and C24 respectively. The second end of resistor R18 is connected to the non-inverting input of the first operational amplifier. The second end of resistor R25 is grounded. The second end of capacitor C21 is connected to the non-inverting input of the first operational amplifier. The second end of capacitor C24 is grounded.

[0020] Optionally, the first input circuit includes a capacitor C18 and a resistor R13;

[0021] The first end of capacitor C18 is connected to the second end of the analog microphone interface, the second end of capacitor C18 is connected to the first end of resistor R13, and the second end of resistor R13 is connected to the non-inverting input of the first operational amplifier.

[0022] Optionally, the first feedback circuit includes capacitor C14, resistor R9, capacitor C10, and resistor R10;

[0023] The first end of resistor R10 is connected to the output terminal of the first operational amplifier, the second end of resistor R10 is connected to the inverting input terminal of the first operational amplifier, the first end of resistor R9 is connected to the inverting input terminal of the first operational amplifier, the second end of resistor R9 is connected to the first end of capacitor C14, the second end of capacitor C14 is grounded, the first end of capacitor C10 is connected to the output terminal of the first operational amplifier, and the second end of capacitor C10 is connected to the inverting input terminal of the first operational amplifier.

[0024] Optionally, the secondary operational amplifier unit includes a second operational amplifier, a second input circuit, and a second feedback circuit;

[0025] The non-inverting input terminal of the second operational amplifier is connected to the output terminal of the power supply circuit;

[0026] The input terminal of the second input circuit is connected to the output terminal of the first operational amplifier, and the output terminal of the second input circuit is connected to the non-inverting input terminal of the second operational amplifier.

[0027] The first terminal of the second feedback circuit is grounded, and the second terminal of the second feedback circuit is connected to the output terminal of the second operational amplifier.

[0028] The output of the second operational amplifier is connected to the input of the rectifier module.

[0029] Optionally, the second input circuit includes a capacitor C17 and a resistor R12. The first end of the capacitor C17 is connected to the output terminal of the first operational amplifier, the second end of the capacitor C17 is connected to the first end of the resistor R12, and the second end of the resistor R12 is connected to the inverting input terminal of the second operational amplifier.

[0030] The second feedback circuit includes a resistor R11 and a capacitor C16. The first end of the resistor R11 is connected to the inverting input terminal of the second operational amplifier, and the second end of the resistor R11 is connected to the output terminal of the second operational amplifier. The first end of the capacitor C16 is connected to the inverting input terminal of the second operational amplifier, and the second end of the capacitor C16 is connected to the output terminal of the second operational amplifier.

[0031] The non-inverting input terminal of the second operational amplifier is connected to the power supply circuit through resistor R21.

[0032] Optionally, the rectifier module includes capacitor C15, resistor R15, diode D1, capacitor C19, resistor R14, Zener diode D2, and resistor R60.

[0033] The first end of capacitor C15 is connected to the output terminal of the signal amplification module. The second end of capacitor C15 is connected to the first end of resistor R15 and the anode of diode D1. The second end of resistor R15 is grounded. The cathode of diode D1 is connected to the first end of resistor R60. The second end of resistor R60 is connected to the main control chip of the digital conference host. The first end of capacitor C19 is connected to the cathode of diode D1. The second end of capacitor C19 is grounded. The first end of resistor R14 is connected to the cathode of diode D1. The second end of resistor R14 is grounded. The cathode of Zener diode D2 is connected to the cathode of diode D1. The anode of Zener diode D2 is grounded.

[0034] The present invention provides a simulated microphone activation detection device, comprising a simulated microphone interface, a signal amplification module, a rectification module, and a phantom power supply module. The first end of the simulated microphone interface is connected to a phantom microphone, and the second end of the simulated microphone interface is connected to the input end of the signal amplification module. The output end of the signal amplification module is connected to the input end of the rectification module. The signal amplification module amplifies the micro-voltage signal generated by the phantom microphone in response to environmental noise. The output end of the rectification module is connected to the main control chip of the digital conference host, and the rectification module rectifies the electrical signal output by the signal amplification module. The input end of the phantom power supply module is externally connected to the digital conference host, and the output end of the phantom power supply module is connected to the second end of the simulated microphone interface. The device detects the weak voltage signal generated by the phantom microphone collecting environmental noise, amplifies and rectifies it, and then sends it to the main control chip of the digital conference host. The digital conference host thus determines that the phantom microphone is activated, facilitating the management of the phantom microphone by the digital conference host. Attached Figure Description

[0035] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0036] Figure 1 This is a schematic diagram of the structure of a simulated microphone open detection device provided in an embodiment of the present invention;

[0037] Figure 2 This is a schematic diagram of the structure of an analog microphone interface and a signal preprocessing module provided in an embodiment of the present invention;

[0038] Figure 3 This is a schematic diagram of the structure of a signal amplification module provided in an embodiment of the present invention;

[0039] Figure 4 This is a schematic diagram of the structure of a rectifier module provided in an embodiment of the present invention;

[0040] Figure 5 This is a schematic diagram of a phantom power supply module provided in an embodiment of the present invention. Detailed Implementation

[0041] To make the technical problems solved by the present invention, the technical solutions adopted, and the technical effects achieved clearer, the technical solutions of the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0043] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature. Moreover, the terms "first" and "second" are used merely for descriptive distinction and have no specific meaning.

[0044] Figure 1 This is a schematic diagram of a simulated microphone open detection device provided in an embodiment of the present invention, as shown below. Figure 1 As shown, the simulated microphone open detection device includes:

[0045] The analog microphone interface J has its first end connected to a phantom analog microphone, and its second end connected to the input of the signal amplification module 110. The phantom analog microphone is used to acquire sound signals and convert them into electrical signals.

[0046] The signal amplification module 110 has its output terminal connected to the input terminal of the rectifier module 120. The signal amplification module 110 is used to amplify the micro voltage signal generated by the phantom analog microphone in response to ambient noise.

[0047] The rectifier module 120 is connected to the main control chip MCU of the digital conference host. The rectifier module 120 is used to rectify the electrical signal output by the signal amplification module 110 so that it meets the input requirements of the main control chip MCU.

[0048] The phantom power module 130 has its input connected to an external digital conference host, which supplies power to it. Its output is connected to the second terminal of the analog microphone interface J. The phantom power module 130 supplies power to the phantom analog microphone via the analog microphone interface J.

[0049] For example, if the phantom microphone is muted, it has no signal output, the signal amplification module 110 and the rectifier module 120 have no output, and the pins connecting the main control chip MCU to the rectifier module 120 have no signal input. The digital conference host then determines that the phantom microphone is muted. If the phantom microphone is on, it can collect weak ambient noise and convert it into a weak AC voltage signal. The signal amplification module 110 amplifies the voltage signal, and the rectifier module 120 rectifies the amplified voltage signal, converting it into DC power, which is then sent to the main control chip MCU of the digital conference host. The digital conference host then determines that the phantom microphone is on, thus enabling online management of the phantom microphone, such as online microphone on / off status display, EQ adjustment, and microphone sensitivity adjustment.

[0050] The analog microphone activation detection device provided in this embodiment of the invention includes an analog microphone interface, a signal amplification module, a rectification module, and a phantom power supply module. The first end of the analog microphone interface is connected to a phantom analog microphone, the second end of the analog microphone interface is connected to the input end of the signal amplification module, and the output end of the signal amplification module is connected to the input end of the rectification module. The signal amplification module amplifies the micro-voltage signal generated by the phantom analog microphone in response to ambient noise. The output end of the rectification module is connected to the main control chip of the digital conference host, and the rectification module rectifies the electrical signal output by the signal amplification module. The input of the phantom power module is connected to the digital conference host, and the output of the phantom power module is connected to the second end of the analog microphone interface. If the phantom analog microphone is in the "on" state, it can collect weak ambient noise and convert it into a weak AC voltage signal. The signal amplification module amplifies the voltage signal, and the rectification module rectifies the amplified voltage signal to convert it into DC power, which is then sent to the main control chip of the digital conference host. The digital conference host then determines that the phantom analog microphone is in the "on" state, and thus enables online management of the phantom analog microphone.

[0051] In some embodiments of the present invention, such as Figure 1As shown, the analog microphone activation detection device also includes a signal preprocessing module 140. The input of the signal preprocessing module 140 is connected to the second end of the analog microphone interface J, and the output of the signal preprocessing module 140 is connected to the sound card of the digital conference host. For example, when the user is speaking normally, the phantom analog microphone collects the sound signal, which is then preprocessed by the signal preprocessing module 140 to obtain MIC_IN1, such as through voltage regulation, filtering, and amplification. This signal is then sent to the sound card of the digital conference host, where the sound card processes the signal to simulate different types of microphones.

[0052] Figure 2 This is a schematic diagram of the structure of an analog microphone interface and signal preprocessing module provided in an embodiment of the present invention, as shown below. Figure 2 As shown, the analog microphone interface J can be a XLR connector. The left end of the analog microphone interface J is used to connect a phantom microphone, and the right end has three pins. The first pin is grounded, and the second and third pins are used to transmit the differential signal acquired by the phantom microphone. The phantom microphone generates a differential signal in response to the sound signal and transmits it through the second and third pins of the analog microphone interface J. The first end of capacitor C6 is connected to the second pin of the analog microphone interface J, and the second end a of capacitor C6 is connected to the first input terminal of the signal preprocessing module 140. The first end of capacitor C7 is connected to the third pin of the analog microphone interface J, and the second end b of capacitor C7 is connected to the second input terminal of the signal preprocessing module 140. The second and third pins are connected to the output terminal Vout of the phantom power supply module 130 through resistors R8 and R7, respectively. The second end b of capacitor C7 is connected to the input terminal of the signal amplification module 110, supplying the MIC_CHK signal to the signal amplification module 110.

[0053] The signal preprocessing module 140 includes resistors R1 and R2, capacitors C5 and C9, resistors R3 and R4, resistors R6, capacitors C8 and C1, and operational amplifier U10A. Specifically, the first terminal of resistor R2 is connected to the second terminal of capacitor C6, and the second terminal of resistor R2 is grounded. The first terminal of capacitor C5 is connected to the second terminal of capacitor C6, and the second terminal of capacitor C6 is grounded. The first terminal of resistor R5 is connected to the second terminal of capacitor C7, and the second terminal of resistor R5 is grounded. The first terminal of capacitor C9 is connected to the second terminal of capacitor C7, and the second terminal of capacitor C9 is grounded. The first terminal of resistor R3 is connected to the second terminal of capacitor C6, and the second terminal of resistor R3 is connected to the inverting input terminal of operational amplifier U10A. The first terminal of resistor R4 is connected to the second terminal of capacitor C7, and the second terminal of resistor R4 is connected to the non-inverting input terminal of operational amplifier U10A. The first terminal of resistor R6 is connected to the non-inverting input of operational amplifier U10A, and the second terminal of resistor R6 is grounded. The first terminal of capacitor C8 is connected to the second terminal of resistor R4, and the second terminal of capacitor C8 is grounded. The first terminal of resistor R1 is connected to the non-inverting input of operational amplifier U10A, and the second terminal of resistor R1 is connected to the output of operational amplifier U10A. The first terminal of capacitor C1 is connected to the non-inverting input of operational amplifier U10A, and the second terminal of capacitor C1 is connected to the output of operational amplifier U10A.

[0054] Figure 3 This is a schematic diagram of the structure of a signal amplification module provided in an embodiment of the present invention, as shown below. Figure 3 As shown, in some embodiments of the present invention, the signal amplification module includes a first-stage operational amplifier unit 111 and a second-stage operational amplifier unit 112. The input terminal of the first-stage operational amplifier unit 111 is connected to the second terminal of the analog microphone interface J (i.e., the second terminal of capacitor C7), the output terminal of the first-stage operational amplifier unit 111 is connected to the input terminal of the second-stage operational amplifier unit 112, and the output terminal c of the second-stage operational amplifier unit 112 is connected to the input terminal of the rectifier module. By amplifying the weak AC voltage signal twice, the weak AC voltage signal can be amplified several hundred times, which is convenient for detection by the digital conference host.

[0055] For example, such as Figure 3As shown, the first-stage operational amplifier unit 111 includes a first operational amplifier U1A, a power supply circuit 1111, a first input circuit 1112, and a first feedback circuit 1113. The input terminal of the power supply circuit 1111 is connected to a reference power supply (5V), and its output terminal is connected to the non-inverting input terminal of the first operational amplifier U1A. The input terminal of the first input circuit 1112 is connected to the second terminal of the analog microphone interface J (i.e., the second terminal of capacitor C7), and its output terminal is connected to the non-inverting input terminal of the first operational amplifier U1A. The first terminal of the first feedback circuit 1113 is grounded, and its second terminal is connected to the output terminal of the first operational amplifier U1A. The output terminal of the first operational amplifier U1A is connected to the input terminal of the second-stage operational amplifier unit 112.

[0056] For example, such as Figure 3 As shown, the power supply circuit 1111 includes resistors R20, R18, R25, capacitors C21 and C24. The first terminal of resistor R20 is connected to the reference power supply. The second terminal of resistor R20 is connected to the first terminals of resistors R18, R25, C21, and C24 respectively. The second terminal of resistor R18 is connected to the non-inverting input terminal of the first operational amplifier U1A. The second terminal of resistor R25 is grounded. The second terminal of capacitor C21 is connected to the non-inverting input terminal of the first operational amplifier U1A. The second terminal of capacitor C24 is grounded.

[0057] For example, such as Figure 3 As shown, the first input circuit 1112 includes a capacitor C18 and a resistor R13. The first end of the capacitor C18 is connected to the second end of the analog microphone interface J (i.e., the second end of the capacitor C7), the second end of the capacitor C18 is connected to the first end of the resistor R13, and the second end of the resistor R13 is connected to the non-inverting input terminal of the first operational amplifier U1A.

[0058] For example, such as Figure 3 As shown, the first feedback circuit 1113 includes capacitor C14, resistor R9, capacitor C10, and resistor R10. The first end of resistor R10 is connected to the output terminal of the first operational amplifier U1A, and the second end of resistor R10 is connected to the inverting input terminal of the first operational amplifier U1A. The first end of resistor R9 is connected to the inverting input terminal of the first operational amplifier U1A, and the second end of resistor R9 is connected to the first end of capacitor C14. The second end of capacitor C14 is grounded. The first end of capacitor C10 is connected to the output terminal of the first operational amplifier U1A, and the second end of capacitor C10 is connected to the inverting input terminal of the first operational amplifier U1A.

[0059] In some embodiments of the present invention, such as Figure 3As shown, the two-stage operational amplifier unit 112 includes a second operational amplifier U1B, a second input circuit 1121, and a second feedback circuit 1122. The non-inverting input terminal of the second operational amplifier U1B is connected to the output terminal of the power supply circuit 1111. The input terminal of the second input circuit 1121 is connected to the output terminal of the first operational amplifier U1A, and the output terminal of the second input circuit 1121 is connected to the non-inverting input terminal of the second operational amplifier U1B. The first terminal of the second feedback circuit 1122 is grounded, and the second terminal of the second feedback circuit 1122 is connected to the output terminal of the second operational amplifier U1B. The output terminal c of the second operational amplifier U1B is connected to the input terminal of the rectifier module.

[0060] For example, such as Figure 3 As shown, the second input circuit 1121 includes a capacitor C17 and a resistor R12. The first end of capacitor C17 is connected to the output terminal of the first operational amplifier U1A, and the second end of capacitor C17 is connected to the first end of resistor R12. The second end of resistor R12 is connected to the inverting input terminal of the second operational amplifier U1B. The second feedback circuit 1122 includes a resistor R11 and a capacitor C16. The first end of resistor R11 is connected to the inverting input terminal of the second operational amplifier U1B, and the second end of resistor R11 is connected to the output terminal of the second operational amplifier U1B. The first end of capacitor C16 is connected to the inverting input terminal of the second operational amplifier U1B, and the second end of capacitor C16 is connected to the output terminal of the second operational amplifier U1B. The non-inverting input terminal of the second operational amplifier U1B is connected to the power supply circuit 1111 through resistor R21.

[0061] Figure 4 This is a schematic diagram of the structure of a rectifier module provided in an embodiment of the present invention, exemplarily, as shown below. Figure 4 As shown, the rectifier module includes capacitor C15, resistor R15, diode D1, capacitor C19, resistor R14, Zener diode D2, and resistor R60. The first terminal of capacitor C15 is connected to the output terminal c of the signal amplification module. The second terminal of capacitor C15 is connected to both the first terminal of resistor R15 and the anode of diode D1. The second terminal of resistor R15 is grounded. The cathode of diode D1 is connected to the first terminal of resistor R60. The second terminal of resistor R60 is connected to the main control chip (MCU) of the digital conference host for outputting the signal CHK. The first terminal of capacitor C19 is connected to the cathode of diode D1. The second terminal of capacitor C19 is grounded. The first terminal of resistor R14 is connected to the cathode of diode D1. The second terminal of resistor R14 is grounded. The cathode of Zener diode D2 is connected to the cathode of diode D1. The anode of Zener diode D2 is grounded.

[0062] Figure 5 This is a schematic diagram of the structure of a phantom power module provided in an embodiment of the present invention, exemplarily, as shown below. Figure 5As shown, the phantom power supply module includes a power chip U2, resistors R23 and R27, capacitors C23, R30, and C28, inductor L1, capacitor C25, resistors R26, R24, and R28, diode D3, capacitors C22 and C20, and diode D4.

[0063] Specifically, the VIN pin of power chip U2 is connected to the power supply (36V) of the digital conferencing host. The first end of resistor R23 is connected to the EN enable pin of power chip U2, and the second end of resistor R23 is also connected to the power supply (36V) of the digital conferencing host. The first end of resistor R27 is connected to the EN enable pin of power chip U2, and the second end of resistor R27 is grounded. The first end of capacitor C23 is connected to the power supply (36V) of the digital conferencing host, and the second end of capacitor C23 is grounded. The first end of capacitor C28 is connected to the VCC pin of power chip U2, and the second end of capacitor C28 is grounded. The first end of resistor R30 is connected to the RT pin of power chip U2, and the second end of resistor R30 is grounded. The first end of inductor L1 is connected to the VIN pin of power chip U2, and the second end of inductor L1 is connected to the SW pin of power chip U2. The anode of diode D3 is connected to the SW pin of power chip U2, and the cathode of diode D3 is connected to the anode of diode D4. The cathode of diode D4 serves as the output terminal Vout of the phantom power module, outputting a 48V DC voltage. The first terminal of capacitor C22 is connected to the cathode of diode D3, and the second terminal of capacitor C22 is grounded. The first terminal of capacitor C20 is connected to the cathode of diode D3, and the second terminal of capacitor C20 is grounded. The first terminal of capacitor C25 is connected to the COMP pin of power chip U2, and the second terminal of capacitor C25 is connected to the first terminal of resistor R26. The second terminal of resistor R26 is connected to the first terminals of resistors R24 and R28 respectively. The second terminal of resistor R24 ​​is connected to the anode of diode D4, and the second terminal of resistor R28 is grounded. The feedback pin FB of power chip U2 is connected to the first terminal of resistor R28.

[0064] In the description herein, it should be understood that the terms "upper," "lower," "left," "right," etc., are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of description and simplification of operation, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0065] In the description of this specification, references to terms such as "an embodiment," "example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example.

[0066] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style of the specification is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

[0067] The technical principles of the present invention have been described above with reference to specific embodiments. These descriptions are merely for explaining the principles of the invention and should not be construed as limiting the scope of protection of the invention in any way. Based on this explanation, those skilled in the art can readily conceive of other specific embodiments of the invention without inventive effort, and these embodiments will all fall within the scope of protection of the present invention.

Claims

1. A device for detecting microphone activation / deactivation in a simulated microphone, characterized in that, include: An analog microphone interface, wherein the first end of the analog microphone interface is connected to a phantom analog microphone, and the second end of the analog microphone interface is connected to the input end of a signal amplification module; A signal amplification module, the output of which is connected to the input of a rectifier module, is used to amplify the micro-voltage signal generated by the phantom microphone in response to ambient noise. A rectifier module, the output of which is connected to the main control chip of the digital conference host, is used to rectify the electrical signal output by the signal amplification module; The phantom power module has its input connected to the digital conference host and its output connected to the second end of the analog microphone interface.

2. The simulated microphone open detection device according to claim 1, characterized in that, It also includes a signal preprocessing module, the input of which is connected to the second end of the analog microphone interface, and the output of which is connected to the sound card of the digital conference host.

3. The simulated microphone open detection device according to claim 1, characterized in that, The signal amplification module includes a first-stage operational amplifier unit and a second-stage operational amplifier unit. The input terminal of the first-stage operational amplifier unit is connected to the second terminal of the analog microphone interface, the output terminal of the first-stage operational amplifier unit is connected to the input terminal of the second-stage operational amplifier unit, and the output terminal of the second-stage operational amplifier unit is connected to the input terminal of the rectifier module.

4. The simulated microphone open detection device according to claim 3, characterized in that, The first-stage operational amplifier unit includes a first operational amplifier, a power supply circuit, a first input circuit, and a first feedback circuit; The input terminal of the power supply circuit is connected to the reference power supply, and the output terminal of the power supply circuit is connected to the non-inverting input terminal of the first operational amplifier. The input terminal of the first input circuit is connected to the second terminal of the analog microphone interface, and the output terminal of the first input circuit is connected to the non-inverting input terminal of the first operational amplifier. The first terminal of the first feedback circuit is grounded, and the second terminal of the first feedback circuit is connected to the output terminal of the first operational amplifier. The output terminal of the first operational amplifier is connected to the input terminal of the second operational amplifier unit.

5. The simulated microphone open detection device according to claim 4, characterized in that, The power supply circuit includes resistors R20, R18, and R25, and capacitors C21 and C24. The first end of resistor R20 is connected to the reference power supply. The second end of resistor R20 is connected to the first ends of resistor R18, resistor R25, capacitor C21, and capacitor C24, respectively. The second end of resistor R18 is connected to the non-inverting input of the first operational amplifier. The second end of resistor R25 is grounded. The second end of capacitor C21 is connected to the non-inverting input of the first operational amplifier. The second end of capacitor C24 is grounded.

6. The simulated microphone open detection device according to claim 4, characterized in that, The first input circuit includes a capacitor C18 and a resistor R13; The first end of capacitor C18 is connected to the second end of the analog microphone interface, the second end of capacitor C18 is connected to the first end of resistor R13, and the second end of resistor R13 is connected to the non-inverting input of the first operational amplifier.

7. The simulated microphone open detection device according to claim 4, characterized in that, The first feedback circuit includes capacitor C14, resistor R9, capacitor C10, and resistor R10; The first end of resistor R10 is connected to the output terminal of the first operational amplifier, the second end of resistor R10 is connected to the inverting input terminal of the first operational amplifier, the first end of resistor R9 is connected to the inverting input terminal of the first operational amplifier, the second end of resistor R9 is connected to the first end of capacitor C14, the second end of capacitor C14 is grounded, the first end of capacitor C10 is connected to the output terminal of the first operational amplifier, and the second end of capacitor C10 is connected to the inverting input terminal of the first operational amplifier.

8. The analog microphone open detection device according to any one of claims 4-7, characterized in that, The second operational amplifier unit includes a second operational amplifier, a second input circuit, and a second feedback circuit; The non-inverting input terminal of the second operational amplifier is connected to the output terminal of the power supply circuit; The input terminal of the second input circuit is connected to the output terminal of the first operational amplifier, and the output terminal of the second input circuit is connected to the non-inverting input terminal of the second operational amplifier. The first terminal of the second feedback circuit is grounded, and the second terminal of the second feedback circuit is connected to the output terminal of the second operational amplifier. The output of the second operational amplifier is connected to the input of the rectifier module.

9. The analog microphone open detection device according to claim 8, characterized in that: The second input circuit includes a capacitor C17 and a resistor R12. The first end of the capacitor C17 is connected to the output terminal of the first operational amplifier, the second end of the capacitor C17 is connected to the first end of the resistor R12, and the second end of the resistor R12 is connected to the inverting input terminal of the second operational amplifier. The second feedback circuit includes a resistor R11 and a capacitor C16. The first end of the resistor R11 is connected to the inverting input terminal of the second operational amplifier, and the second end of the resistor R11 is connected to the output terminal of the second operational amplifier. The first end of the capacitor C16 is connected to the inverting input terminal of the second operational amplifier, and the second end of the capacitor C16 is connected to the output terminal of the second operational amplifier. The non-inverting input terminal of the second operational amplifier is connected to the power supply circuit through resistor R21.

10. The simulated microphone open detection device according to claim 1, characterized in that, The rectifier module includes capacitor C15, resistor R15, diode D1, capacitor C19, resistor R14, Zener diode D2, and resistor R60. The first end of capacitor C15 is connected to the output terminal of the signal amplification module. The second end of capacitor C15 is connected to the first end of resistor R15 and the anode of diode D1. The second end of resistor R15 is grounded. The cathode of diode D1 is connected to the first end of resistor R60. The second end of resistor R60 is connected to the main control chip of the digital conference host. The first end of capacitor C19 is connected to the cathode of diode D1. The second end of capacitor C19 is grounded. The first end of resistor R14 is connected to the cathode of diode D1. The second end of resistor R14 is grounded. The cathode of Zener diode D2 is connected to the cathode of diode D1. The anode of Zener diode D2 is grounded.

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