A MEMS microphone

Abstract

The application provides a MEMS microphone, comprising a substrate and a MEMS chip, an ASIC chip, a pressure sensing module and a pressure data tuning processing module arranged on the substrate; wherein the pressure sensing module is arranged at the bottom of the MEMS chip. The pressure sensing module is used for sensing the pressure at the bottom of the MEMS chip and outputting a first pressure signal; the ASIC chip is used for converting the pressure signal output by the MEMS chip into a second pressure signal and outputting the second pressure signal to the pressure data tuning processing module; and the pressure data tuning processing module is used for compensating the second pressure signal according to the first pressure signal and outputting the compensated second pressure signal as a target pressure signal. The MEMS microphone can sense the pressure of different use interfaces through the pressure sensing module, compensate the output of the MEMS chip, and thus keep the pressure sensitivity of the MEMS microphone consistent in different use scenarios.

Description

Technical Field

[0001] This application relates to the field of acoustic technology, specifically to a MEMS microphone. Background Technology

[0002] MEMS microphones are miniature microphones based on microelectromechanical systems (MEMS) technology. They have advantages such as small size, low power consumption, and low cost, and have a wide range of applications in various fields, such as smartphones, wearable devices, in-vehicle voice interaction systems, medical devices, industrial equipment monitoring, security and surveillance.

[0003] MEMS microphones utilize MEMS chips, and the pressure sensitivity of these chips varies significantly depending on the mounting interface (such as packaging structure, substrate material, and bonding method). This variation primarily stems from changes in the mechanical stress transmission path, additional stress introduced by thermal expansion coefficient mismatch, and the impact of packaging on the sensor's dynamic characteristics. Ideally, external pressure should be directly and uniformly transmitted to the MEMS sensitive diaphragm (such as a silicon diaphragm) through the packaging structure, ensuring efficient linear conversion of pressure-deformation-electrical signal. However, the stiffness, thickness, and geometry of the mounting interface alter the stress distribution, leading to decreased effective stress transmission efficiency or nonlinear distortion.

[0004] Therefore, how to maintain consistent pressure sensitivity of MEMS microphones under different usage scenarios is a technical problem that urgently needs to be solved in this field. Utility Model Content

[0005] The purpose of this application is to provide a MEMS microphone that can maintain consistent pressure sensitivity under different usage scenarios.

[0006] This application provides a MEMS microphone, including:

[0007] A substrate and a MEMS chip, an ASIC chip, a pressure sensing module, and a pressure data tuning and processing module disposed on the substrate; wherein the pressure sensing module is disposed at the bottom of the MEMS chip;

[0008] The pressure sensing module is connected to the pressure data tuning and processing module, the pressure data tuning and processing module is connected to the ASIC chip, and the MEMS chip is connected to the ASIC chip.

[0009] The pressure sensing module is used to sense the pressure at the bottom of the MEMS chip and output a first pressure signal to the pressure data tuning and processing module.

[0010] The ASIC chip is used to convert the pressure signal output by the MEMS chip into a second pressure signal and then output it to the pressure data tuning and processing module.

[0011] The pressure data tuning processing module is used to compensate the second pressure signal according to the first pressure signal, and output the compensated second pressure signal as the target pressure signal.

[0012] In one possible implementation, the pressure sensing module and the pressure data tuning and processing module are integrated into one unit.

[0013] In one possible implementation, the pressure sensing module and the pressure data tuning and processing module are separate units, and the two are connected by a gold wire.

[0014] In one possible implementation, the pressure sensing module is made of zinc oxide material.

[0015] In one possible implementation, the pressure sensing module is made of acrylate material.

[0016] In one possible implementation, the projected area of ​​the pressure sensing module on the substrate is larger than the projected area of ​​the MEMS chip on the substrate.

[0017] In one possible implementation, the pressure data tuning processing module is connected to the ASIC chip via gold wires, and the MEMS chip is connected to the ASIC chip via gold wires.

[0018] In one possible implementation, the MEMS microphone further includes:

[0019] The housing, the substrate, and the MEMS chip, ASIC chip, pressure sensing module, and pressure data tuning and processing module disposed on the substrate are all disposed within the housing, and the housing is used for electromagnetic shielding.

[0020] The MEMS microphone provided in this application includes: a substrate and a MEMS chip, an ASIC chip, a pressure sensing module, and a pressure data tuning and processing module disposed on the substrate; wherein, the pressure sensing module is disposed at the bottom of the MEMS chip. The pressure sensing module is used to sense pressure at the bottom of the MEMS chip and output a first pressure signal to the pressure data tuning and processing module; the ASIC chip is used to convert the pressure signal output by the MEMS chip into a second pressure signal and output it to the pressure data tuning and processing module; the pressure data tuning and processing module is used to compensate the second pressure signal according to the first pressure signal and output the compensated second pressure signal as a target pressure signal. Compared with the prior art, the MEMS microphone of this application can sense the pressure of different user interfaces through the pressure sensing module, thereby compensating the output of the MEMS chip, thus ensuring that the pressure sensitivity of the MEMS microphone remains consistent under different usage scenarios. Attached Figure Description

[0021] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0022] Figure 1 The present application provides a schematic diagram of the structure of a MEMS microphone according to some embodiments;

[0023] Figure 2 This application provides a schematic diagram of the structure of another MEMS microphone according to some embodiments;

[0024] Explanation of reference numerals in the attached figures:

[0025] Substrate 10, MEMS chip 20, ASIC chip 30, pressure sensing module 40, pressure data tuning and processing module 50. Detailed Implementation

[0026] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0027] It should be noted that if the embodiments of this application involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0028] Furthermore, if the embodiments of this application involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the meaning of "and / or" throughout the text is to include three parallel solutions; for example, "A and / or B" includes solution A, solution B, or a solution that simultaneously satisfies A and B. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed in this application.

[0029] It should be noted that, unless otherwise stated, the technical or scientific terms used in this application shall have the ordinary meaning as understood by one of ordinary skill in the art to which this application pertains.

[0030] ASIC is an abbreviation for Application-Specific Integrated Circuit, a type of dedicated chip designed specifically for a particular need. Examples include dedicated audio and video processors, and many dedicated AI chips can also be considered a type of ASIC. The characteristics of ASICs are their focus on specific user needs. Compared to general-purpose integrated circuits, ASICs offer advantages in mass production, such as smaller size, lower power consumption, improved reliability, higher performance, enhanced security, and lower cost.

[0031] MEMS (Micro-Electro-Mechanical Systems) chips are a technology that integrates micro-mechanical components, sensors, actuators, and electronic components onto a single microchip. MEMS chips are widely used in smart devices, healthcare, automotive electronics, aerospace, and other fields, characterized by their small size, light weight, low power consumption, and wide range of applications. MEMS sensors are a crucial component of MEMS chips, primarily used for detecting various environmental or biological signals, such as temperature, pressure, and acceleration, as well as analyzing fluids and gases. MEMS sensors convert the measured physical signals into electrical signals through miniaturized mechanical structures. For example, an acceleration MEMS sensor can measure acceleration by using a miniature cantilever beam that displaces under acceleration, and then converting this physical displacement into an electrical signal through changes in capacitance or resistance. This miniaturization and integration feature makes MEMS sensors widely used in smartphones, wearable devices, and automotive safety systems.

[0032] Please refer to Figure 1 It illustrates a schematic diagram of a MEMS microphone provided by some embodiments of this application, such as... Figure 1 As shown, the MEMS microphone includes: a substrate 10 and a MEMS chip 20, an ASIC chip 30, a pressure sensing module 40, and a pressure data tuning and processing module 50 disposed on the substrate 10.

[0033] The pressure sensing module 40 is located at the bottom of the MEMS chip 20. The pressure sensing module 40 is connected to the pressure data tuning and processing module 50, which is also connected to the ASIC chip 30. The MEMS chip 20 is connected to the ASIC chip 30. In a MEMS microphone, the MEMS chip can convert sound into changes in capacitance and resistance, while the ASIC chip can convert these changes into electrical signals.

[0034] Specifically, the pressure sensing module 40 and the pressure data tuning and processing module 50 can be configured as separate units (e.g., ...). Figure 1 As shown), it can also be a one-piece setup (such as...). Figure 2 As shown in the diagram, the two are connected by gold wires. The pressure data tuning processing module 50 is connected to the ASIC chip 30 via gold wires, and the MEMS chip 20 is connected to the ASIC chip 30 via gold wires. The gold wires are used to provide circuit connections.

[0035] The pressure sensing module 40 is used to sense the pressure on the bottom of the MEMS chip 20 and output a first pressure signal to the pressure data tuning and processing module 50. Specifically, the substrate 10 can be a PCB substrate. The pressure sensing module 40 is disposed between the MEMS chip 20 and the substrate 10, and can sense the pressure on the bottom of the MEMS chip, thereby measuring the stress on the MEMS chip mounted on the user interface.

[0036] The ASIC chip 30 is used to convert the pressure signal output by the MEMS chip into a second pressure signal and then output it to the pressure data tuning and processing module 50.

[0037] The pressure data tuning and processing module 50 is used to compensate the second pressure signal according to the first pressure signal, and output the compensated second pressure signal as the target pressure signal.

[0038] Specifically, the working principle of the MEMS microphone mentioned in this application is as follows:

[0039] The pressure sensing module 40 senses pressure on the bottom of the MEMS chip 20 and outputs a first pressure signal to the pressure data tuning and processing module 50. The ASIC chip 30 converts the pressure signal output by the MEMS chip 20 into a second pressure signal and outputs it to the pressure data tuning and processing module 50. The pressure data tuning and processing module 50 compensates for the second pressure signal based on the first pressure signal and outputs the compensated second pressure signal as the target pressure signal. Therefore, the MEMS microphone of this application can sense pressure at different user interfaces through the pressure sensing module, thereby compensating for the output of the MEMS chip and ensuring that the pressure sensitivity of the MEMS microphone remains consistent under different usage scenarios. This application can perform product performance data tuning on the MEMS microphone, enabling the product to adapt to different pressure scenarios and usage schemes.

[0040] In some implementations, such as Figure 1 As shown, the projected area of ​​the pressure sensing module 40 on the substrate 10 is larger than the projected area of ​​the MEMS chip 20 on the substrate 10. The large area of ​​the pressure sensing module 40 ensures that it can completely cover the bottom of the MEMS chip 20, thereby accurately sensing the bottom pressure of the MEMS chip.

[0041] In some implementations, the pressure sensing module 40 is made of zinc oxide. Zinc oxide (ZnO) is a typical piezoelectric material; when subjected to mechanical pressure, its crystal structure deforms, causing the centers of positive and negative charges to shift, thereby generating charges on the material surface (piezoelectric effect). Pressure can be detected by collecting the charge signals through electrodes.

[0042] In other embodiments, the pressure sensing module 40 is made of acrylate material. Acrylate is a polymer that is typically formed into a composite system by doping the material with conductive fillers (such as carbon nanotubes or silver nanowires). When subjected to pressure, the contact network of the conductive filler deforms, causing a change in the material's resistance (piezoresistive effect), thereby sensing the pressure.

[0043] In some implementations, the pressure data tuning processing module 50 may employ a SIP99X1 chip, the SIP99X1 series being a high-precision, high-reliability bridge sensor signal conditioning chip with fast response characteristics.

[0044] In some embodiments, the MEMS microphone further includes:

[0045] The housing, the substrate 10, and the MEMS chip 20, ASIC chip 30, pressure sensing module 40, and pressure data tuning and processing module 50 disposed on the substrate are all housed within the housing. The housing serves as electromagnetic shielding and also protects the various components within it. The components within the housing can also be encapsulated with flexible adhesive to protect the gold wires, ASIC chip, pressure data tuning and processing module, etc.

[0046] The MEMS microphone provided in this embodiment includes: a substrate and a MEMS chip, an ASIC chip, a pressure sensing module, and a pressure data tuning processing module disposed on the substrate; wherein, the pressure sensing module is disposed at the bottom of the MEMS chip. The pressure sensing module is used to sense pressure at the bottom of the MEMS chip and output a first pressure signal to the pressure data tuning processing module; the ASIC chip is used to convert the pressure signal output by the MEMS chip into a second pressure signal and output it to the pressure data tuning processing module; the pressure data tuning processing module is used to compensate the second pressure signal according to the first pressure signal and output the compensated second pressure signal as a target pressure signal. Compared with the prior art, the MEMS microphone of this application can sense the pressure of different user interfaces through the pressure sensing module, thereby compensating the output of the MEMS chip, thus ensuring that the pressure sensitivity of the MEMS microphone remains consistent in different usage scenarios.

[0047] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application.

Claims

1. A MEMS microphone, characterized in that, include: A substrate and a MEMS chip, an ASIC chip, a pressure sensing module, and a pressure data tuning and processing module disposed on the substrate; wherein the pressure sensing module is disposed at the bottom of the MEMS chip; The pressure sensing module is connected to the pressure data tuning and processing module, the pressure data tuning and processing module is connected to the ASIC chip, and the MEMS chip is connected to the ASIC chip. The pressure sensing module is used to sense the pressure at the bottom of the MEMS chip and output a first pressure signal to the pressure data tuning and processing module. The ASIC chip is used to convert the pressure signal output by the MEMS chip into a second pressure signal and then output it to the pressure data tuning and processing module. The pressure data tuning processing module is used to compensate the second pressure signal according to the first pressure signal, and output the compensated second pressure signal as the target pressure signal.

2. The MEMS microphone according to claim 1, characterized in that, The pressure sensing module and the pressure data tuning and processing module are integrated into one unit.

3. The MEMS microphone according to claim 1, characterized in that, The pressure sensing module and the pressure data tuning and processing module are separate units, and the two are connected by a gold wire.

4. The MEMS microphone according to claim 1, characterized in that, The pressure sensing module is made of zinc oxide material.

5. The MEMS microphone according to claim 1, characterized in that, The pressure sensing module is made of acrylate material.

6. The MEMS microphone according to claim 1, characterized in that, The projected area of ​​the pressure sensing module on the substrate is larger than the projected area of ​​the MEMS chip on the substrate.

7. The MEMS microphone according to claim 1, characterized in that, The pressure data tuning and processing module is connected to the ASIC chip via gold wires, and the MEMS chip is connected to the ASIC chip via gold wires.

8. The MEMS microphone according to any one of claims 1 to 7, characterized in that, The MEMS microphone also includes: The housing, the substrate, and the MEMS chip, ASIC chip, pressure sensing module, and pressure data tuning and processing module disposed on the substrate are all disposed within the housing, and the housing is used for electromagnetic shielding.

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