Anti-static application circuits, circuit boards, microphones, and microphones for microphones.

Abstract

This application discloses an anti-static application circuit, a printed circuit board, a microphone, and a microphone. The anti-static application circuit for the microphone includes a field-effect transistor (FET), a first capacitor, a first resistor, and a varistor, wherein: the gate of the FET is connected to a ground terminal via the microphone's acoustic-to-electrical conversion unit; the source of the FET is directly connected to the ground terminal; the first capacitor is connected between the drain of the FET and the ground terminal; the first resistor and the varistor are connected in series between the drain of the FET and the ground terminal. This anti-static application circuit for the microphone possesses excellent anti-interference capabilities, effectively resisting interference from widely existing 2.4G, 5G, and 6G frequency bands, and exhibits excellent anti-static performance.

Description

Technical Field

[0001] This application relates to the field of microphone technology, specifically to an anti-static application circuit, circuit board, microphone, and microphone for use in microphones. Background Technology

[0002] The application environment for microphones is becoming increasingly complex, and their electronic circuits are susceptible to electromagnetic interference, affecting the voice quality of the final call. To improve user experience, microphone products themselves must possess excellent anti-interference capabilities, effectively resisting interference from the widely prevalent 2.4G, 5G, and 6G frequency bands. Furthermore, static electricity issues must also be addressed. Utility Model Content

[0003] The main technical problem addressed by this application is to provide an anti-static application circuit, circuit board, microphone, and microphone for use in microphones, which helps to resist interference and static electricity.

[0004] In a first aspect, this application provides an anti-static application circuit for a microphone, the microphone including a sound-to-electric conversion unit, and the application circuit including a field-effect transistor (FET), a first capacitor, a first resistor, and a varistor, wherein: the gate of the FET is connected to a ground terminal via the sound-to-electric conversion unit of the microphone; the source of the FET is directly connected to the ground terminal; the first capacitor is connected between the drain of the FET and the ground terminal; and the first resistor and the varistor are connected in series between the drain of the FET and the ground terminal.

[0005] In some alternative implementations, the microphone is an electret condenser microphone and the field-effect transistor is a junction field-effect transistor.

[0006] In some alternative implementations, a first end of the first resistor is connected to the drain of the field-effect transistor, a second end of the first resistor is connected to a first end of the varistor, and a second end of the varistor is connected to ground.

[0007] In some alternative implementations, the application circuit further includes: a second resistor connected between a second terminal of the first resistor and the operating voltage; and a second capacitor connected between a second terminal of the first resistor and the output terminal.

[0008] In some alternative embodiments, the capacitance of the first capacitor is 33pF, the resistance of the first resistor is 330Ω, and the resistance of the varistor is 10pF.

[0009] Secondly, this application provides a printed circuit board including an anti-static application circuit for a microphone as described in the first aspect.

[0010] Thirdly, this application provides an electret condenser microphone, the electret condenser microphone including a printed circuit board, the printed circuit board including the anti-static application circuit for the microphone as described in the first aspect.

[0011] Fourthly, this application provides a microphone, the microphone comprising an electret condenser microphone as described in the third aspect.

[0012] As can be seen from the above technical solutions, this application has the following advantages:

[0013] This application provides an anti-static circuit for microphones, exhibiting excellent anti-interference and anti-static capabilities. The first capacitor serves as a filter and decoupler, smoothing voltage fluctuations and reducing the impact of power supply noise and electromagnetic interference on the circuit. The first resistor limits current, protecting other components in the circuit or used to set a specific voltage or current level. The first resistor can also work in conjunction with the first capacitor to reduce electromagnetic interference. A varistor protects the circuit from voltage spikes and transients, effectively resisting electrostatic discharge and electromagnetic interference caused by voltage spikes. In summary, this application circuit effectively resists interference from the widely prevalent 2.4GHz, 5GHz, and 6GHz frequency bands, and demonstrates excellent resistance to electrostatic discharge, meeting Level 4 anti-static requirements. Attached Figure Description

[0014] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments and the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a circuit diagram of an anti-static application circuit for a microphone according to Embodiment 1 of this application;

[0016] Figure 2 This is a circuit diagram of an anti-static application circuit for a microphone according to Embodiment 2 of this application. Detailed Implementation

[0017] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present application.

[0018] The terms "first," "second," "third," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or apparatuses.

[0019] The following detailed descriptions will be provided through specific embodiments.

[0020]

Example 1

[0021] refer to Figure 1 This application provides an anti-static application circuit for a microphone. The microphone can be an electret condenser microphone, including a sound-to-electric conversion unit 10. Optionally, the sound-to-electric conversion unit 10 may include a diaphragm and metal plates separated by insulating spacers to form a parallel-plate capacitor, with the diaphragm and metal plates serving as the two electrodes of the capacitor. An electret is disposed on the diaphragm or the metal plates. The working principle of the sound-to-electric conversion unit 10 is as follows: when sound pressure is received, the diaphragm vibrates under the action of sound pressure, and the capacitance of the parallel-plate capacitor changes with the vibration of the diaphragm, thereby causing a voltage change and completing the sound-to-electric conversion. The capacitance between the diaphragm and the metal plates is relatively small, typically tens of pF. Therefore, the output impedance of the sound-to-electric conversion unit 10 is very high, approximately tens of megohms or more.

[0022] refer to Figure 1 The anti-static application circuit for a microphone disclosed in this application structurally includes a field-effect transistor (FET) 10, a first capacitor C1, a first resistor R1, and a varistor V1. This application circuit can be disposed on a printed circuit board inside the microphone. The printed circuit board can be encapsulated by the microphone's housing (which may be a metal housing) and together with the housing to form a cavity. The cavity houses the electroacoustic conversion unit 10, and may also contain components such as metal rings and insulating rings. This application circuit is connected to the electroacoustic conversion unit 10.

[0023] The field-effect transistor 11 is used to implement impedance transformation, reducing the output impedance of the voltage signal output from the acoustic-to-electric conversion unit 10 to below several thousand ohms. Specifically, the field-effect transistor 11 can be a junction field-effect transistor. The field-effect transistor 11 includes three terminals: drain (D), source (S), and gate (G).

[0024] The connection relationships of the application circuit are as follows: the gate (G) of the field-effect transistor 11 is connected to the ground terminal 23 via the acoustic-to-electric conversion unit 10; the source (S) of the field-effect transistor 11 is directly connected to the ground terminal 23; the first capacitor C1 is connected between the drain (D) of the field-effect transistor 11 and the ground terminal 23; the first resistor R1 and the varistor V1 are connected in series between the drain (D) of the field-effect transistor 11 and the ground terminal 23. Specifically, the first end of the first resistor R1 is connected to the drain (D) of the field-effect transistor 11, the second end of the first resistor R1 is connected to terminal 1 and simultaneously connected to the first end of the varistor V1, and the second end of the varistor V1 is connected to the ground terminal 23. Terminal 1 can be a connection terminal on the printed circuit board of the microphone. The printed circuit board can also have a connection terminal for connecting to the ground terminal as terminal 2. The source (S) of the field-effect transistor 11, the first capacitor C1, and the varistor, etc., that need to be grounded, can be connected to terminal 2, and then connected to the ground terminal 23 through terminal 2.

[0025] In some alternative implementations, the application circuit further includes: a second resistor R L The second capacitor C0; wherein, the second resistor R L A first resistor R1 is connected between its second terminal and the operating voltage (Vs) 21; a second capacitor is connected between the second terminal of the first resistor R1 and the output terminal (output) 22. The second resistor R... L Typically used as a load resistor, it helps set the operating current in the circuit and protects other components from damage caused by excessive current. The second capacitor C0 is usually used as a filter capacitor at the output; it stores and releases charge to smooth the output voltage, reduce voltage fluctuations and noise, thereby improving power supply stability. Additionally, the second resistor R... L It can also be used together with the second capacitor C0 to form an RC filter to smooth the output voltage and further reduce high-frequency noise and electromagnetic interference.

[0026] In some alternative implementations, the first capacitor C1 has a capacitance of 33pF, the first resistor R1 has a resistance of 330Ω, and the varistor V1 has a resistance of 10pF. The operating voltage (Vs) 21 can be between 1V and 10V, for example, 5V.

[0027] The anti-static application circuit for microphones disclosed in this application possesses excellent anti-interference and anti-static capabilities. The first capacitor serves as a filter and decoupler, smoothing voltage fluctuations and reducing the impact of power supply noise and electromagnetic interference on the circuit. The first resistor limits current, protecting other components in the circuit or used to set a specific voltage or current level. The first resistor can also work in conjunction with the first capacitor to reduce electromagnetic interference. The varistor protects the circuit from voltage spikes and transients, effectively resisting electrostatic discharge and electromagnetic interference caused by voltage spikes. In summary, this application circuit effectively resists interference from the widely prevalent 2.4GHz, 5GHz, and 6GHz frequency bands, and exhibits excellent resistance to electrostatic discharge, meeting Level 4 anti-static requirements.

[0028]

Example 2

[0029] refer to Figure 2 This application provides an anti-static application circuit for a microphone. Figure 2 The application circuit shown is Figure 1 The application circuit shown is similar, except that in Figure 2 In the application circuit shown, the second capacitor C2 replaces the varistor V1.

[0030] The second capacitor C2 is mainly used for filtering and decoupling. It can smooth voltage fluctuations and reduce the impact of power supply noise and electromagnetic interference (EMI) on the circuit. Together with the first resistor R1 and the first capacitor C1, it can form an RC filter to reduce high-frequency noise and electromagnetic interference.

[0031]

Example 3

[0032] This application also provides a printed circuit board that may include an anti-static application circuit for a microphone, as provided in Embodiment 1 or 2.

[0033]

Example 4

[0034] This application also provides an electret condenser microphone, which includes a printed circuit board that may include anti-static application circuitry for the microphone as provided in Embodiment 1 or 2.

[0035]

Example 5

[0036] This application also provides a microphone, which may include an electret condenser microphone as provided in Embodiment 4.

[0037] The technical solution of this application has been described in detail above through specific embodiments. In the above embodiments, the descriptions of each embodiment have their own emphasis, and for parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0038] It should be understood that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Those skilled in the art can modify the technical solutions described in the above embodiments, or make equivalent substitutions for some of the technical features; however, these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and protection scope of the technical solutions of the embodiments of this application.

Claims

1. An anti-static application circuit for a microphone, characterized by, The application circuit includes a field-effect transistor, a first capacitor, a first resistor, and a varistor, wherein: The gate of the field-effect transistor is connected to the ground terminal via the acoustic-to-electric conversion unit of the microphone; The source of the field-effect transistor is directly connected to the ground terminal; The first capacitor is connected between the drain of the field-effect transistor and the ground terminal; The first resistor and the varistor are connected in series between the drain of the field-effect transistor and the ground terminal.

2. The anti-static application circuit for a microphone according to claim 1, wherein, The microphone is an electret condenser microphone, and the field-effect transistor is a junction field-effect transistor.

3. The anti-static application circuit for a microphone according to claim 1, wherein, The first end of the first resistor is connected to the drain of the field-effect transistor, the second end of the first resistor is connected to the first end of the varistor, and the second end of the varistor is connected to the ground terminal.

4. The anti-static application circuit for a microphone according to claim 3, wherein, Further includes: The second resistor is connected between the second terminal of the first resistor and the operating voltage; The second capacitor is connected between the second terminal and the output terminal of the first resistor.

5. The anti-static application circuit for a microphone according to claim 1, wherein, The capacitance of the first capacitor is 33pF, the resistance of the first resistor is 330Ω, and the resistance of the varistor is 10pF.

6. A printed circuit board, characterized by The printed circuit board includes an anti-static application circuit for a microphone as described in any one of claims 1-5.

7. An electret condenser microphone comprising a printed circuit board, characterized in that The printed circuit board includes an anti-static application circuit for a microphone as described in any one of claims 1-5.

8. A microphone, characterized by The microphone includes an electret condenser microphone as described in claim 7.

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