Bone conduction microphone amplifier

Abstract

The utility model discloses a bone conduction microphone amplifier. Comprising an external voltage stabilization unit and a signal amplification unit, the external voltage stabilization unit comprises a voltage stabilization chip and a filter circuit, an output pin of the voltage stabilization chip is electrically connected with one end of the filter circuit, the other end of the filter circuit is electrically connected with the signal amplification unit, and the signal amplification unit comprises a first triode, an adjustable resistor and a second triode. An external voltage stabilizing unit is additionally arranged on a power supply circuit of the bone conduction microphone to realize the consistency of the power supply voltage of the microphone; the external voltage stabilizing unit is added, so that the power supply voltage range of the microphone is more stable, and the signal interference of the emission signal frequency of the interphone antenna is reduced. And the anti-interference capability is further improved through the signal amplification unit, so that the pickup effect of the bone conduction microphone is ensured. And when used in cooperation with an interphone in the fire-fighting field, the sound box has a better communication sound quality effect. The microphone can be compatible with interphones in the market, and is good in conversation sound quality effect, strong in anti-interference capability and good in environmental noise resistance.

Description

Technical Field

[0001] The present application relates to the technical field of bone conduction microphones, and in particular to a bone conduction microphone amplifier. Background Art

[0002] In firefighting scenarios, firefighters need to wear helmets and there is a lot of noise at some sites, which requires the microphone to have a high ability to resist environmental noise and to be able to pick up the sound source by fitting on the surface of the firefighting mask. To adapt to the processing of bone conduction microphones, appropriate circuits are required.

[0003] In the prior art, the sound signal collected by the bone conduction microphone is weaker than that of the air conduction microphone, and the commonly used microphone circuit cannot provide good sound quality; relying solely on the op amp analog circuit of the op amp integrated chip of the traditional microphone on the market, the anti-interference ability is poor, and a good acoustic signal processing effect cannot be achieved, and the sound pickup effect is not good. In addition, the microphone bias voltage provided by some walkie-talkies is only about 0.8V, while the optimal working voltage of the bone conduction microphone is 1-3V, and the power supply is insufficient, resulting in the sound signal collected by the bone conduction microphone being relatively unstable, affecting the actual use effect. Utility Model Content

[0004] The main technical problem solved by the present application is to provide a bone conduction microphone amplifier to solve the problem that the sound pickup effect of the bone conduction microphone is unstable and poor.

[0005] In order to solve the above technical problems, a technical solution adopted in the present application is to provide a bone conduction microphone amplifier, comprising: an external voltage stabilizing unit and a signal amplifying unit, the external voltage stabilizing unit is connected to the positive electrode of the microphone and is used to stabilize the power supply voltage of the microphone, and the signal amplifying unit is used to process the signal of the microphone; the external voltage stabilizing unit comprises a voltage stabilizing chip and a filtering circuit, the input pin and the control pin of the voltage stabilizing chip are used to electrically connect the microphone power supply, the output pin of the voltage stabilizing chip is electrically connected to one end of the filtering circuit, and the other end of the filtering circuit is electrically connected to the signal amplifying unit, the signal amplifying unit comprises a first transistor, an adjustable resistor and a second transistor, the base of the first transistor is electrically connected to the filtering circuit, the emitter of the first transistor is electrically connected to the negative electrode of the microphone, the collector of the first transistor is electrically connected to the input end of the adjustable resistor, the output end of the adjustable resistor is electrically connected to the negative electrode of the microphone, the adjustment end of the adjustable resistor is electrically connected to the base of the second transistor, the emitter of the second transistor is electrically connected to the negative electrode of the microphone, and the collector of the second transistor is electrically connected to the positive electrode of the microphone.

[0006] In some embodiments, the input pin and output pin of the voltage stabilizing chip are electrically connected to the positive electrode of a polarity capacitor, and the negative electrodes of the polarity capacitors are grounded respectively. Two resistors are also connected in series between the input pin of the voltage stabilizing chip and the microphone power supply, and a capacitor is electrically connected between the two resistors and then grounded.

[0007] In some embodiments, the filter circuit includes five resistors connected in series in sequence, and the circuits before the five resistors are respectively electrically connected to the positive electrodes of polar capacitors, and the negative electrodes of the polar capacitors are respectively grounded.

[0008] In some embodiments, a resistor and a capacitor are connected in series between the filter circuit and the base of the first transistor in sequence, a first magnetic bead and a capacitor are connected between the resistor and the capacitor, and then the cathode of the microphone is connected, and the capacitor is connected in parallel with a first electrostatic diode; one end of the first electrostatic diode is connected to the cathode of the microphone, and the other end is connected to the anode of the microphone.

[0009] In some embodiments, a capacitor and a resistor are connected in series between the collector of the first transistor and the adjustable resistor, the adjustment end of the adjustable resistor is electrically connected to a capacitor and then to the base of the second transistor; the output end of the adjustable resistor is electrically connected to a resistor and then to the negative electrode of the microphone.

[0010] In some embodiments, the bases of the first transistor and the second transistor are respectively electrically connected to a resistor and a capacitor in parallel, and then electrically connected to a resistor and a polar capacitor, and then electrically connected to the negative electrode of the microphone.

[0011] In some embodiments, a capacitor is electrically connected between the base and emitter of the first transistor and between the base and emitter of the second transistor.

[0012] In some embodiments, the collector of the second transistor is electrically connected to the second magnetic bead and then to the positive electrode of the microphone; a second electrostatic diode is also connected to the circuit between the second magnetic bead and the positive electrode of the microphone, and the second electrostatic diode is electrically connected to the negative electrode of the microphone; a capacitor is also connected to the circuit between the second magnetic bead and the positive electrode of the microphone and then electrically connected to the negative electrode of the microphone; the capacitor is also electrically connected to the third magnetic bead and then to ground.

[0013] In some embodiments, the external voltage stabilizing unit and the signal amplifying unit are also connected to an adapter and a connecting male head, the adapter including a current mutual inductance interface, an intercom interface, a speaker positive electrode interface, a speaker negative electrode interface, a microphone positive electrode interface and a power interface; the connecting male head includes a current mutual inductance male head, a microphone positive electrode male head, an intercom male head, a microphone negative electrode male head, a speaker negative electrode male head and a speaker positive electrode male head; the current mutual inductance interface, the intercom interface, the speaker positive electrode interface, the speaker negative electrode interface and the microphone positive electrode interface of the adapter are respectively connected to the current mutual inductance male head, the intercom male head, the speaker negative electrode male head and the speaker positive electrode male head of the connecting male head; a key switch is connected in series between the intercom interface of the adapter and the intercom male head of the connecting male head; the microphone positive electrode interface of the adapter is electrically connected to the second electrostatic diode; the microphone positive electrode male head of the connecting male head is electrically connected to the first electrostatic diode.

[0014] In some embodiments, the connecting male connector is used to electrically connect to the connecting female connector, and the connecting female connector includes a microphone positive female connector, a microphone negative female connector, a speaker negative female connector, and a speaker positive female connector; the microphone positive female connector and the microphone negative female connector are electrically connected, and the speaker negative female connector and the speaker positive female connector are electrically connected.

[0015] The beneficial effects of the present application are as follows: In the present application, an external voltage stabilizing unit is added to the power supply circuit of the bone conduction microphone to achieve the consistency of the microphone power supply voltage; adding an external voltage stabilizing unit can ensure that the microphone power supply voltage range is more stable and reduce the signal interference caused by the signal frequency transmitted by the intercom antenna. The signal amplification unit is used to further improve the anti-interference ability, thereby ensuring the sound pickup effect of the bone conduction microphone. When used in conjunction with an intercom in the fire protection field, it has better communication sound quality. It is compatible with intercoms on the market, has good call sound quality, strong anti-interference ability, and good resistance to environmental noise. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a circuit diagram according to an embodiment of the present application;

[0017] Figure 2 is a circuit diagram of an external voltage stabilizing unit according to an embodiment of the present application;

[0018] Figure 3 is a circuit diagram of a signal amplification unit according to an embodiment of the present application;

[0019] Figure 4 is a schematic structural diagram of an adapter according to an embodiment of the present application;

[0020] Figure 5 is a structural schematic diagram of a male connector according to an embodiment of the present application;

[0021] Figure 6 It is a schematic diagram of the structure of connecting a female connector according to an embodiment of the present application.

[0022] Figure 7 It is a structural schematic diagram according to an embodiment of the present application. DETAILED DESCRIPTION

[0023] In order to facilitate the understanding of the present application, the present application is described in more detail below in conjunction with the accompanying drawings and specific embodiments. The preferred embodiments of the present application are provided in the accompanying drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described in this specification. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present application more thorough and comprehensive.

[0024] It should be noted that, unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as those commonly understood by those skilled in the art of the present application. The terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used in this specification includes any and all combinations of one or more related listed items.

[0025] Figure 1-Figure 7 An embodiment of the bone conduction microphone amplifier of the present application is shown, including an external voltage stabilizing unit 10 and a signal amplifying unit 20. The external voltage stabilizing unit 10 is connected to the positive electrode of the microphone, and is used to stabilize the microphone power supply voltage and enable it to fully work so as to give full play to the performance of the microphone. The signal amplifying unit 20 is connected to the microphone after being driven by the bias power supply of the intercom microphone, and is used to perform signal processing on the sound quality and volume of the microphone to ensure that the microphone has sufficient voltage to drive the microphone unit so that it can fully work. The external voltage stabilizing unit 10 includes a voltage stabilizing chip U1 and an RC filtering circuit. The input pin and control pin of the voltage stabilizing chip U1 are used to electrically connect to the microphone power supply. The output pin of the voltage stabilizing chip U1 is electrically connected to one end of the filtering circuit. The other end of the filtering circuit is electrically connected to the signal amplifying unit 20. The signal amplifying unit 20 includes a first transistor Q1, an adjustable resistor R9 and a second transistor Q4. The base of the first transistor Q1 is electrically connected to the filtering circuit, the emitter of the first transistor Q1 is electrically connected to the negative electrode M- of the microphone, the collector of the first transistor Q1 is electrically connected to the input end of the adjustable resistor R9, the output end of the adjustable resistor R9 is electrically connected to the negative electrode M- of the microphone, the adjustment end of the adjustable resistor R9 is electrically connected to the base of the second transistor Q4, the emitter of the second transistor Q4 is electrically connected to the negative electrode M- of the microphone, and the collector of the second transistor Q4 is electrically connected to the positive electrode MIC+ of the microphone.

[0026] In the present application, an external voltage stabilizing unit 10 is added to the power supply circuit of the bone conduction microphone to achieve the consistency of the microphone power supply voltage; adding the external voltage stabilizing unit 10 can ensure that the microphone power supply voltage range is more stable and reduce the signal interference caused by the signal frequency transmitted by the intercom antenna. The signal amplification unit 20 is used to further improve the anti-interference ability, thereby ensuring the sound pickup effect of the bone conduction microphone. When used in conjunction with an intercom in the fire protection field, it has better communication sound quality. It is compatible with intercoms on the market, has good call sound quality, strong anti-interference ability, and good resistance to environmental noise.

[0027] In some embodiments, Figure 2 As shown, the model of the voltage regulator chip U1 is NJM2882, the input pin of the voltage regulator chip U1 is electrically connected to the positive electrode of a polar capacitor C2, the output pin of the voltage regulator chip U1 is electrically connected to the positive electrode of a polar capacitor C26, the negative electrodes of the polar capacitors C2 and C26 are grounded respectively, and two resistors R37 and R40 are connected in series between the input pin of the voltage regulator chip U1 and the microphone power supply, and a capacitor C27 is electrically connected between the two resistors R37 and R40 and then grounded. The other pins of the voltage regulator chip are grounded. The voltage regulator chip U1 can control the input voltage fluctuation range within a stable output range. It can automatically adjust when the input voltage changes to ensure the consistency of the microphone power supply voltage and prevent the microphone from being affected by voltage fluctuations when picking up sound.

[0028] In some embodiments, Figure 2 As shown, the filter circuit includes five resistors (R41, R47, R48, R49 and R50) connected in series, and the positive electrodes of the polarity capacitors (C29, C39, C13, C15 and C44) are electrically connected to the circuit before the five resistors (R41, R47, R48, R49 and R50), and the negative electrodes of the polarity capacitors (C29, C39, C13, C15 and C44) are grounded. Adding a filter circuit can ensure that the power supply voltage range of the microphone is more stable and reduce signal interference caused by the frequency of the signal transmitted by the intercom antenna.

[0029] In some embodiments, Figure 3As shown, a resistor R5- and a capacitor C6 are connected in series between the filter circuit and the base of the first transistor Q1. The first magnetic bead L1 and the capacitor C5- are connected between the resistor R5- and the capacitor C6, and then the negative electrode M- of the microphone is connected. The capacitor C5- is connected in parallel with the first electrostatic diode D3; one end of the first electrostatic diode D3 is connected to the negative electrode M- of the microphone, and the other end is connected to the positive electrode MIC+ of the microphone. A capacitor C10 and a resistor R8 are connected in series between the collector of the first transistor Q1 and the adjustable resistor R9. The adjustment end of the adjustable resistor R9 is electrically connected to a capacitor C11 and then to the base of the second transistor Q4; the output end of the adjustable resistor R9 is electrically connected to a resistor R10 and then to the negative electrode M- of the microphone. The first transistor Q1 is electrically connected to a parallel resistor R4 and a capacitor C9, and then electrically connected to a resistor R6- and a polarity capacitor C1, and then electrically connected to the negative electrode M- of the microphone. The base of the second transistor Q4 is electrically connected to a parallel resistor R15 and a capacitor C14, and then electrically connected to a resistor R7 and a polarity capacitor C1, and then electrically connected to the negative electrode M- of the microphone. A capacitor C7 is electrically connected between the base and the emitter of the first transistor Q1, and a capacitor C12 is electrically connected between the base and the emitter of the second transistor Q4. The base of the second transistor Q4 is also electrically connected to a resistor R11, and then electrically connected to the negative electrode M- of the microphone. The emitter of the second transistor Q4 is electrically connected to a resistor R12, and then electrically connected to the negative electrode M- of the microphone. The collector of the second transistor Q4 is electrically connected to the second magnetic bead L2, and then electrically connected to the positive electrode MIC+ of the microphone; the circuit between the second magnetic bead L2 and the positive electrode MIC+ of the microphone is also connected to the second electrostatic diode D2, and the second electrostatic diode D2 is electrically connected to the negative electrode M- of the microphone; the circuit between the second magnetic bead L2 and the positive electrode MIC+ of the microphone is also connected to a capacitor C45 and then electrically connected to the negative electrode M- of the microphone; the capacitor C45 is also electrically connected to the third magnetic bead L3 and then grounded. For the microphone filter circuit to process the signal interference caused by the unstable power supply of the intercom, the transistor has better anti-interference ability than the traditional microphone amplifier integrated chip on the market. Directly using the bias voltage in the microphone to power the transistor can make the transistor work stably when the bias voltage is low, ensuring the stability of the power supply to the transistor.

[0030] In some embodiments, Figure 4 and Figure 5As shown, the external voltage stabilizing unit 10 and the signal amplifying unit 20 are also connected to an adapter 30 and a connecting male connector 40, and the adapter 30 is an SP3J adapter. The connecting male connector is a Hirose male connector. The adapter 30 includes a current mutual inductance interface 301, an intercom interface 302, a speaker positive electrode interface 303, a speaker negative electrode interface 304, a microphone positive electrode interface 305, and a power interface 306; the connecting male connector 40 includes a power interface 401, a microphone positive electrode male connector 402, an intercom male connector 403, a microphone negative electrode male connector 404, a speaker negative electrode male connector 405, and a speaker positive electrode male connector 406; the current mutual inductance interface 301, the intercom interface 302, the speaker positive electrode interface 303, the speaker negative electrode interface 304, and the microphone positive electrode interface 305 of the adapter 30 are respectively connected to the power interface 401, the intercom male connector 403, the speaker negative electrode male connector 405, and the speaker positive electrode male connector 406 of the connecting male connector 40. A key switch S1 and a resistor R28 are connected in series between the intercom interface 302 of the adapter 30 and the intercom male connector 403 of the connecting male connector 40; and are grounded. The current mutual inductance interface 301 of the adapter 30 is also connected to a resistor SP3-R1 and a third electrostatic diode D1 in parallel. The microphone positive electrode interface 305 of the adapter 30 is electrically connected to the second electrostatic diode D2. The microphone positive electrode male connector 402 of the connecting male connector 40 is electrically connected to the first electrostatic diode D3; the speaker positive electrode male connector 406 is also electrically connected to the negative electrode of a polarity capacitor C31; a capacitor C5 is electrically connected between the microphone positive electrode male connector 402 and the microphone negative electrode male connector 404.

[0031] In some embodiments, Figure 6 As shown, the male connector 40 is used to electrically connect the female connector 50, and the female connector 50 is a Hirose female connector. The female connector 50 includes a microphone positive female connector 502, a microphone negative female connector 504, a speaker negative female connector 505, and a speaker positive female connector 506; the microphone MIC is electrically connected between the microphone positive female connector 502 and the microphone negative female connector 504, and the speaker SPK is electrically connected between the speaker negative female connector 505 and the speaker positive female connector 506. The two connectors 501 and 503 of the female connector 50 are directly connected. The female connector 50 is connected to the air pager speaker and the air pager microphone.

[0032] In some embodiments, Figure 7 As shown, the external voltage stabilizing unit 10 and the signal amplifying unit 20 are arranged in the intercom switch 1, the adapter 30 is electrically connected to the intercom switch 1 through the conductive first winding wire 3, the connecting male head 40 is electrically connected to the intercom switch 1 through the conductive second winding wire 4, the connecting female head 50 is arranged on the intercom, and the connecting male head 40 and the connecting female head 50 are adapted to be connected.

[0033] It can be seen that the present application discloses a bone conduction microphone amplifier. In the present application, an external voltage stabilizing unit is added to the power supply circuit of the bone conduction microphone to achieve the consistency of the microphone power supply voltage; adding an external voltage stabilizing unit can ensure that the microphone power supply voltage range is more stable and reduce the signal interference caused by the signal frequency transmitted by the intercom antenna. The signal amplification unit is used to further improve the anti-interference ability, thereby ensuring the sound pickup effect of the bone conduction microphone. When used in conjunction with an intercom in the fire protection field, it has better communication sound quality. It is compatible with intercoms on the market, has good call sound quality, strong anti-interference ability, and good resistance to environmental noise.

[0034] The above are merely embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structural transformations made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A bone conduction microphone amplifier, characterized in that: It includes an external voltage stabilizing unit and a signal amplifying unit, wherein the external voltage stabilizing unit is connected to the positive electrode of the microphone and is used to stabilize the power supply voltage of the microphone, and the signal amplifying unit is used to process the signal of the microphone; The external voltage stabilizing unit includes a voltage stabilizing chip and a filtering circuit, the input pin and the control pin of the voltage stabilizing chip are used to electrically connect to the microphone power supply, the output pin of the voltage stabilizing chip is electrically connected to one end of the filtering circuit, and the other end of the filtering circuit is electrically connected to the signal amplifying unit, the signal amplifying unit includes a first transistor, an adjustable resistor and a second transistor, the base of the first transistor is electrically connected to the filtering circuit, the emitter of the first transistor is electrically connected to the negative electrode of the microphone, the collector of the first transistor is electrically connected to the input end of the adjustable resistor, the output end of the adjustable resistor is electrically connected to the negative electrode of the microphone, the adjustment end of the adjustable resistor is electrically connected to the base of the second transistor, the emitter of the second transistor is electrically connected to the negative electrode of the microphone, and the collector of the second transistor is electrically connected to the positive electrode of the microphone.

2. The bone conduction microphone amplifier according to claim 1, characterized in that: The input pin and output pin of the voltage stabilizing chip are electrically connected to the positive electrode of a polarity capacitor, and the negative electrodes of the polarity capacitors are grounded respectively. Two resistors are also connected in series between the input pin of the voltage stabilizing chip and the microphone power supply, and a capacitor is electrically connected between the two resistors and then grounded.

3. The bone conduction microphone amplifier according to claim 1, characterized in that: The filter circuit includes five resistors connected in series in sequence, and the circuits before the five resistors are respectively electrically connected to the positive electrodes of polar capacitors, and the negative electrodes of the polar capacitors are respectively grounded.

4. The bone conduction microphone amplifier according to claim 1, characterized in that: A resistor and a capacitor are connected in series between the filter circuit and the base of the first transistor in sequence, a first magnetic bead and a capacitor are connected between the resistor and the capacitor, and then the cathode of the microphone is connected, and the capacitor is connected in parallel with a first electrostatic diode; one end of the first electrostatic diode is connected to the cathode of the microphone, and the other end is connected to the anode of the microphone.

5. The bone conduction microphone amplifier according to claim 1, characterized in that: A capacitor and a resistor are connected in series between the collector of the first transistor and the adjustable resistor. The adjustment end of the adjustable resistor is electrically connected to a capacitor and then to the base of the second transistor; the output end of the adjustable resistor is electrically connected to a resistor and then to the negative electrode of the microphone.

6. The bone conduction microphone amplifier according to claim 5, characterized in that: The bases of the first transistor and the second transistor are respectively electrically connected to a resistor and a capacitor in parallel, and then electrically connected to a resistor and a polar capacitor, and then electrically connected to the negative electrode of the microphone.

7. The bone conduction microphone amplifier according to claim 6, characterized in that: A capacitor is electrically connected between the base and emitter of the first transistor and between the base and emitter of the second transistor.

8. The bone conduction microphone amplifier according to claim 4, characterized in that: The collector of the second transistor is electrically connected to the second magnetic bead and then to the positive electrode of the microphone; a second electrostatic diode is also connected to the circuit between the second magnetic bead and the positive electrode of the microphone, and the second electrostatic diode is electrically connected to the negative electrode of the microphone; a capacitor is also connected to the circuit between the second magnetic bead and the positive electrode of the microphone and then electrically connected to the negative electrode of the microphone; the capacitor is also electrically connected to the third magnetic bead and then to ground.

9. The bone conduction microphone amplifier according to claim 8, characterized in that: The external voltage stabilizing unit and the signal amplifying unit are also connected to an adapter and a connecting male head, and the adapter includes a current mutual inductance interface, an intercom interface, a speaker positive electrode interface, a speaker negative electrode interface, a microphone positive electrode interface and a power interface; the connecting male head includes a current mutual inductance male head, a microphone positive electrode male head, an intercom male head, a microphone negative electrode male head, a speaker negative electrode male head and a speaker positive electrode male head; the current mutual inductance interface, the intercom interface, the speaker positive electrode interface, the speaker negative electrode interface and the microphone positive electrode interface of the adapter are respectively connected to the current mutual inductance male head, the intercom male head, the speaker negative electrode male head and the speaker positive electrode male head of the connecting male head; a key switch is connected in series between the intercom interface of the adapter and the intercom male head of the connecting male head; the microphone positive electrode interface of the adapter is electrically connected to the second electrostatic diode; the microphone positive electrode male head of the connecting male head is electrically connected to the first electrostatic diode.

10. The bone conduction microphone amplifier according to claim 9, characterized in that: The connecting male head is used to electrically connect to the connecting female head, and the connecting female head includes a microphone positive female head, a microphone negative female head, a speaker negative female head and a speaker positive female head; the microphone positive female head and the microphone negative female head are electrically connected to the microphone, and the speaker negative female head and the speaker positive female head are electrically connected to the speaker.

Images