Directive microphone and electronic device
The directional microphone design with internal acoustic chambers and strategic sound hole placement addresses the issue of poor directionality in MEMS microphones, enhancing call quality and reducing production costs.
Patent Information
- Application Number
- CN202510322885.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-18
- Publication Date
- 2025-07-15
AI Technical Summary
The existing MEMS microphones have low directivity in call applications, resulting in poor call quality, and the existing hardware requirements for implementing directional functions are high, power consumption and high cost.
A directional microphone is designed, by setting a sound cavity structure inside the substrate and setting a third acoustic hole opposite to the diaphragm on the surface of the substrate, adjusting the distance between the first acoustic hole and the diaphragm so that the microphone has directional sound pickup capability, combining the ASIC chip and the pad to improve performance.
It realizes the directional sound pickup of the microphone, improves call quality, reduces manufacturing difficulty and production costs, adapts to different scenarios, and improves flexibility and customer experience.
Smart Images
Figure CN120321532A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the technical field of acoustic devices, and more particularly, to a directional microphone and an electronic device. Background Art
[0002] MEMS microphones have the advantages of small size, high performance, and strong sensitivity consistency, but their directivity in call applications is not high, resulting in poor call quality. In the prior art, the directivity function in call applications is usually achieved by means of arrays, voice algorithms, etc., but it has high requirements for the performance of hardware and high power consumption, resulting in high manufacturing costs. Summary of the Invention
[0003] An object of this application is to provide a new technical solution for a directional microphone and an electronic device.
[0004] According to the first aspect of this application, there is provided a directional microphone, including:
[0005] A substrate, inside which an acoustic cavity structure is provided, and on the surface of the substrate, a first sound hole and a second sound hole are provided, and the first sound hole and the second sound hole are interconnected through the acoustic cavity structure;
[0006] A cover body, which is buckled on the surface of the substrate, and a third sound hole is provided on the surface of the substrate or the cover body;
[0007] A MEMS chip, which is arranged inside the cover body, and the MEMS chip includes a diaphragm, a first acoustic cavity and a second acoustic cavity are respectively formed on both sides of the diaphragm, the second sound hole is communicated with the first acoustic cavity, and the third sound hole is communicated with the second acoustic cavity;
[0008] Wherein, the third sound hole is arranged opposite to the diaphragm, and the distance between the first sound hole and the diaphragm is greater than the distance between the third sound hole and the diaphragm.
[0009] Optionally, in one direction of the substrate, the acoustic cavity structure extends from the first end of the substrate to the second end of the substrate, the cover body is located at the first end, and the first sound hole is located at the second end, so that the sound signal close to the first sound hole can be weakened at the diaphragm.
[0010] Optionally, the MEMS chip is arranged on the substrate, the acoustic cavity structure includes a third acoustic cavity and a fourth acoustic cavity which are separated from each other, and the first sound hole and the second sound hole are communicated through the third acoustic cavity;
[0011] The third sound hole is arranged on the surface of the substrate, and a fourth sound hole is also arranged on the surface of the substrate, and the third sound hole and the fourth sound hole are communicated through the fourth acoustic cavity.
[0012] Optionally, the cover body is an integrally formed structure.
[0013] Optionally, the MEMS chip is disposed on the substrate, and the third sound hole is a through hole penetrating the substrate.
[0014] Optionally, the MEMS chip and the third sound hole are both disposed on the cover body, and the MEMS chip is electrically connected to the substrate through the cover body.
[0015] Optionally, the directional microphone further includes a damping sheet, and the damping sheet is disposed at the first sound hole.
[0016] Optionally, the first sound hole is configured as a plurality of microporous structures.
[0017] Optionally, the directional microphone further includes an ASIC chip and a pad. The ASIC chip is disposed inside the cover body and is electrically connected to the substrate and the MEMS chip respectively. The pad is disposed on the surface of the substrate and is electrically connected to the substrate.
[0018] According to a second aspect of the present application, there is provided an electronic device, including: the directional microphone according to the first aspect.
[0019] According to an embodiment of the present application, by providing a sound cavity structure inside the substrate, a first sound hole communicating with the sound cavity structure on the surface of the substrate, and a third sound hole oppositely disposed to the diaphragm, and making the distance between the first sound hole and the diaphragm greater than the distance between the third sound hole and the diaphragm, the microphone can achieve directional sound pickup and effectively improve the call quality.
[0020] Other features and advantages of the present application will become clear through the following detailed description of the exemplary embodiments of the present application with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] The drawings incorporated in and constituting a part of this specification illustrate embodiments of the present application and, together with the description, serve to explain the principles of the present application.
[0022] Figure 1 is one of the schematic diagrams of a directional microphone provided by the present application.
[0023] Figure 2 is another schematic diagram of a directional microphone provided by the present application.
[0024] Figure 3 is still another schematic diagram of a directional microphone provided by the present application.
[0025] Description of the reference numerals:
[0026] 1. Substrate; 11. Acoustic cavity structure; 12. First sound hole; 13. Second sound hole; 14. Fourth sound hole; 15. Third acoustic cavity; 16. Fourth acoustic cavity; 2. Cover body; 21. Third sound hole; 3. MEMS chip; 31. Diaphragm; 32. First acoustic cavity; 33. Second acoustic cavity; 4. ASIC chip; 5. Pad. Detailed implementation manners
[0027] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that: Unless otherwise specifically stated, the relative arrangements of components and steps, numerical expressions and values set forth in these embodiments do not limit the scope of the present application.
[0028] The following description of at least one exemplary embodiment is actually merely illustrative and in no way restricts the present application and its application or use.
[0029] Techniques, methods, and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the techniques, methods, and devices should be regarded as part of the specification.
[0030] In all the examples shown and discussed here, any specific value should be construed as merely exemplary and not as a limitation. Therefore, other examples of the exemplary embodiments may have different values.
[0031] It should be noted that: Similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.
[0032] As Figures 1 to 3 shown, according to a first aspect of the present application, there is provided a directional microphone, comprising: a substrate 1, a cover body 2, and a MEMS chip 3 (Micro-Electro-Mechanical Systems); an acoustic cavity structure 11 is provided inside the substrate 1, a first sound hole 12 and a second sound hole 13 are provided on the surface of the substrate 1, and the first sound hole 12 and the second sound hole 13 are interconnected through the acoustic cavity structure 11; the cover body 2 is buckled on the surface of the substrate 1, and a third sound hole 21 is provided on the surface of the substrate 1 or the cover body 2; the MEMS chip 3 is disposed inside the cover body 2, the MEMS chip 3 includes a diaphragm 31, a first acoustic cavity 32 and a second acoustic cavity 33 are respectively formed on both sides of the diaphragm 31, the second sound hole 13 is communicated with the first acoustic cavity 32, and the third sound hole 21 is communicated with the second acoustic cavity 33; wherein, the third sound hole 21 is disposed opposite to the diaphragm 31, and the distance between the first sound hole 12 and the diaphragm 31 is greater than the distance between the third sound hole 21 and the diaphragm 31.
[0033] Specifically, in the present application, an acoustic cavity structure 11 is provided inside the substrate 1, and the first acoustic hole 12 and the second acoustic hole 13 are connected through the acoustic cavity structure 11. The second acoustic hole 13 is connected to the first acoustic cavity 32 on the first side of the diaphragm 31, so that the sound signal picked up by the first acoustic hole 12 can be transmitted to the first side of the diaphragm 31, thereby driving the diaphragm 31 to vibrate and achieving the purpose of converting the sound signal into an electrical signal. A third acoustic hole 21 is also provided on the cover plate or the substrate 1, and the third acoustic hole 21 is connected to the second acoustic cavity 33 on the second side of the diaphragm 31, so that the sound signal picked up by the third acoustic hole 21 can reach the second side of the diaphragm 31, thereby driving the diaphragm 31 to vibrate and also achieving the purpose of converting the sound signal into an electrical signal. That is, in the above structure of the present application, the microphone has two acoustic holes that can directly pick up external environmental sound signals.
[0034] Furthermore, in the present application, the third acoustic hole 21 is arranged opposite to the position of the diaphragm 31, and the distance between the first acoustic hole 12 and the diaphragm 31 is greater than the distance between the second acoustic hole 13 and the diaphragm 31, so that among the sound signals between the first acoustic hole 12 and the third acoustic hole 21, less sound signals close to the first acoustic hole 12 are picked up, while more sound signals close to the third acoustic hole 21 can be picked up, thereby achieving the directivity of picking up sound signals. In practical applications, the third acoustic hole 21 can be set as the main acoustic hole, and the first acoustic hole 12 can be set as the secondary acoustic hole, effectively improving the call quality of the directional microphone. In addition, by arranging the acoustic cavity structure 11 inside the substrate 1, the acoustic cavity structure 11 can be realized by directly digging holes inside the substrate 1, reducing the manufacturing difficulty, shortening the processing cycle, and reducing the production cost, and also being beneficial to the miniaturized design of the product.
[0035] In the above embodiment, the adjustment of the distance between the first acoustic hole 12 and the diaphragm 31 can be achieved by adjusting parameters such as the shape and size of the acoustic cavity structure 11, or by adjusting the position of the first acoustic cavity 32 on the substrate 1, etc. Specifically, it can be matched and designed according to the actual needs of users. In addition, the position of the third acoustic hole 21 can be set on the cover body 2 or on the surface of the substrate 1. It can be directly connected to the second acoustic cavity 33 or connected through the acoustic cavity structure 11. Specifically, it can be designed according to the sound pickup requirements of the third acoustic hole 21, the setting position or setting method of the MEMS chip 3, etc.
[0036] As Figure 1 shown, the top of the cover body 2 is a PCB structure, and both sides are fixed on the substrate 1 through support structures. When the MEMS chip 3 is inverted and arranged on the top of the cover body 2, the third acoustic hole 21 can be arranged on the top plate of the cover body 2 and opposite to the diaphragm 31 of the MEMS, so that the sound signal can directly pass through the third acoustic hole 21 to the diaphragm 31, so that more sound signals close to the position of the third acoustic hole 21 are picked up. Or, as Figure 2 orFigure 3 As shown, the cover body 2 can be designed as a metal or plastic housing structure, which can protect components such as the internal MEMS chip 3, and the third sound hole 21 can be arranged on the upper surface or the lower surface of the substrate 1, and can be specifically designed according to actual needs, and the present application does not limit this.
[0037] Optionally, in one direction of the substrate 1, the sound cavity structure 11 extends from the first end of the substrate 1 to the second end of the substrate 1, the cover body 2 is located at the first end, and the first sound hole 12 is located at the second end, so that the sound signal close to the first sound hole 12 can be weakened at the diaphragm 31.
[0038] Specifically, as Figure 1 shown, in one embodiment, a part of the sound signal close to the first sound cavity 32 (hereinafter referred to as the first sound signal) reaches one side of the diaphragm 31 via the first sound hole 12, the sound cavity structure 11, the second sound hole 13, and the first sound cavity 32, and another part of the sound signal reaches the other side of the diaphragm 31 via the third sound hole 21 and the second sound cavity 33, and the sound signal close to the third sound hole 21 (hereinafter referred to as the second sound signal) also has the above two paths to reach the diaphragm 31. For example Figure 2 shown, the sound cavity structure 11 includes a third sound cavity 15 and a fourth sound cavity 16, then a part of the first sound signal and the second sound signal respectively reach one side of the diaphragm 31 via the first sound hole 12, the third sound cavity 15, the second sound hole 13, and the first sound cavity 32, and the other part reaches the other side of the diaphragm 31 via the third sound hole 21, the fourth sound cavity 16, and the fourth sound hole 14.
[0039] In practical applications, the phase of the two parts of the first sound signal and the second sound signal when reaching the diaphragm 31 can be adjusted by adjusting the volume of the sound cavity structure 11 (the third sound cavity 15, the fourth sound cavity 16) and the position of the first sound hole 12. As Figure 1 or Figure 2 shown, by arranging the sound cavity structure 11 to extend from the first end of the substrate 1 to the second end of the substrate 1, arranging the cover body 2 at the first end, and arranging the first sound hole 12 at a suitable position at the second end, it can be ensured that the phases of the first sound signal reaching the diaphragm 31 via the two paths are opposite, and the phases of the second sound signal reaching the diaphragm 31 via the two paths are the same. Then, the two parts of the first sound signal will attenuate each other, and the two parts of the second sound signal will enhance each other, so that the microphone has poor sensitivity to the first sound signal and high sensitivity to the second sound signal, further improving the call quality of the directional microphone.
[0040] In the above structural design process, adjustment can also be achieved through the cooperation of the position of the third sound hole 21 to reduce the design difficulty of the overall structure of the microphone.
[0041] Optionally, asFigure 2 and Figure 3 As shown in Figure 3 , the MEMS chip 3 is disposed on the substrate 1. The acoustic cavity structure 11 includes a third acoustic cavity 15 and a fourth acoustic cavity 16 that are separated from each other. The first acoustic hole 12 and the second acoustic hole 13 are communicated through the third acoustic cavity 15. The third acoustic hole 21 is disposed on the surface of the substrate 1, and a fourth acoustic hole 14 is further disposed on the surface of the substrate 1. The third acoustic hole 21 and the fourth acoustic hole 14 are communicated through the fourth acoustic cavity 16.
[0042] Specifically, in this embodiment, the acoustic cavity structure 11 is designed as a third acoustic cavity 15 and a fourth acoustic cavity 16 that are separated from each other, so that a part of the sound signal can reach one side of the diaphragm 31 via the first acoustic hole 12, the third acoustic cavity 15, the second acoustic hole 13, and the first acoustic cavity 32, and the other part reaches the other side of the diaphragm 31 via the third acoustic hole 21, the fourth acoustic cavity 16, and the fourth acoustic hole 14. In practical applications, in order to enable the microphone to adapt to different scenario requirements, the microphone can be adjusted by adjusting multiple parameter information of the first acoustic cavity 32, the second acoustic cavity 33, the first acoustic hole 12, and the third acoustic hole 21, which improves the design flexibility, reduces the design difficulty, makes the processing cost lower, and the call quality higher. For example, the third acoustic hole 21 and the fourth acoustic hole 14 can be disposed opposite to each other, or the fourth acoustic hole 14 can be disposed on the side elevation of the substrate 1. The present application does not limit this.
[0043] In the above embodiment, the MEMS is disposed on the substrate 1 and electrically connected to the substrate 1 made of PCB to realize the conversion between the sound signal and the electrical signal.
[0044] Optionally, as Figure 3 shown, the MEMS chip 3 is disposed on the substrate 1, and the third acoustic hole 21 is a through hole penetrating the substrate 1.
[0045] Specifically, in this embodiment, the third acoustic hole 21 is designed as a through hole penetrating the substrate 1, so that the third acoustic hole 21 can directly reach the diaphragm 31 when disposed on the substrate 1, reducing the attenuation of the sound signal during transmission and further improving the call quality of the microphone. In addition, during the processing, the third acoustic hole 21 is designed as a through hole penetrating the substrate 1, and its processing technology is simple, improving the production efficiency and further reducing the production cost.
[0046] Optionally, as Figure 2 and Figure 3 shown, the cover 2 is an integrally formed structure.
[0047] Specifically, the cover body 2 can protect the MEMS chip 3 and the internal structure, improving the reliability of the product. Designing the cover body 2 as an integrally formed structure can not only improve the overall strength of the structure of the cover body 2, further enhance the safety performance of the product, but also save the assembly process of the product and improve the assembly efficiency. In addition, the integrally formed structure has a high sealing performance, which can improve the sealing performance of the first sound cavity 32 and the second sound cavity 33 and reduce the loss of sound signals. In some embodiments, the cover body 2 can be integrally formed by injection molding or stamping according to specific material categories.
[0048] Optionally, as Figure 1 shown, the MEMS chip 3 and the third sound hole 21 are both arranged on the cover body 2, and the MEMS chip 3 is electrically connected to the substrate 1 through the cover body 2.
[0049] Specifically, in this embodiment, the inverted MEMS chip 3 enables the third sound hole 21 arranged on the cover body 2 to directly communicate with the diaphragm 31, further reducing the attenuation of sound signals and being beneficial to the improvement of the performance of the microphone. Among them, the MEMS chip 3 being electrically connected to the substrate 1 through the cover body 2 means that the top of the cover body 2 and the substrate 1 can both be PCB boards to facilitate the conversion between sound signals and electrical signals.
[0050] Optionally, the directional microphone further includes a damping sheet, and the damping sheet is arranged at the first sound hole 12.
[0051] Specifically, in this embodiment, a damping sheet can be arranged at the first sound hole 12, or the first sound hole 12 can be set as a plurality of microporous structures to increase the acoustic resistance and reduce the sound pressure of the sound signal entering the first sound cavity 32 from the first sound hole 12, so as to improve the call quality of the microphone when the third sound hole 21 is used as the main sound hole. Among them, the damping sheet is made of a damping material, and the microporous structure generally refers to a hole with a pore diameter less than 2 nm.
[0052] Optionally, as Figures 1 to 3 shown, the directional microphone further includes an ASIC chip 4 (Application Specific Integrated Circuit) and a pad 5. The ASIC chip 4 is arranged inside the cover body 2 and is electrically connected to the substrate 1 and the MEMS chip 3 respectively. The pad 5 is arranged on the surface of the substrate 1 and is electrically connected to the substrate 1.
[0053] Specifically, in this embodiment, the ASIC chip 4 can further improve the performance of the microphone, and the pad 5 facilitates the connection of the microphone to external devices. Among them, the pad 5 can be arranged on the upper surface of the substrate 1 or led to the lower surface through internal traces, and can be flexibly set according to the actual application scenario.
[0054] According to a second aspect of the present application, there is provided an electronic device, including: the directional microphone of the first aspect.
[0055] Specifically, in this embodiment, the provided electronic device adopts the directional microphone provided in the first aspect, which has the characteristics of directional sound pickup and relatively high call quality, enabling the electronic device to achieve a better customer experience in terms of the call function. Among them, the electronic device can be a mobile phone, a computer, etc., and the present application does not limit this.
[0056] The differences between the various embodiments were mainly described in the above embodiments. As long as the different optimization features between the various embodiments are not contradictory, they can be combined to form a more optimal embodiment. Considering the simplicity of the text, it will not be elaborated here.
[0057] Although some specific embodiments of the present application have been described in detail by way of examples, those skilled in the art should understand that the above examples are only for illustration and not for limiting the scope of the present application. Those skilled in the art should understand that the above embodiments can be modified without departing from the scope and spirit of the present application. The scope of the present application is defined by the appended claims.
Claims
1. A directional microphone, characterized in that, Comprising: A substrate, within which a sound cavity structure is provided, on the surface of the substrate, a first sound hole and a second sound hole are provided, and the first sound hole and the second sound hole are interconnected through the sound cavity structure; A cover body, which is buckled on the surface of the substrate, and a third sound hole is provided on the surface of the substrate or the cover body; A MEMS chip, which is arranged within the cover body, the MEMS chip includes a diaphragm, a first sound cavity and a second sound cavity are respectively formed on both sides of the diaphragm, the second sound hole is communicated with the first sound cavity, and the third sound hole is communicated with the second sound cavity; Wherein, the third sound hole is arranged opposite to the diaphragm, and the distance between the first sound hole and the diaphragm is greater than the distance between the third sound hole and the diaphragm.
2. The directional microphone according to claim 1, wherein In one direction of the substrate, the sound cavity structure extends from the first end of the substrate to the second end of the substrate, the cover body is located at the first end, and the first sound hole is located at the second end, so that the sound signal close to the first sound hole can be weakened at the diaphragm.
3. The directional microphone according to claim 1 or 2, characterized in that, The MEMS chip is arranged on the substrate, the sound cavity structure includes a third sound cavity and a fourth sound cavity which are separated from each other, and the first sound hole and the second sound hole are communicated through the third sound cavity; The third sound hole is arranged on the surface of the substrate, and a fourth sound hole is further provided on the surface of the substrate, and the third sound hole and the fourth sound hole are communicated through the fourth sound cavity.
4. The directional microphone according to claim 3, characterized in that, The cover body is an integrally formed structure.
5. The directional microphone according to claim 1 or 2, characterized in that, The MEMS chip is arranged on the substrate, and the third sound hole is a through hole penetrating the substrate.
6. The directional microphone according to claim 1 or 2, characterized in that, The MEMS chip and the third sound hole are both arranged on the cover body, and the MEMS chip is electrically connected to the substrate through the cover body.
7. The directional microphone according to claim 1, characterized in that, It further includes a damping sheet, and the damping sheet is arranged at the first sound hole.
8. The directional microphone according to claim 1, wherein The first sound hole is arranged as a plurality of microporous structures.
9. The directional microphone according to claim 1, characterized in that, It further includes an ASIC chip and a pad, the ASIC chip is arranged within the cover body and is respectively electrically connected to the substrate and the MEMS chip, and the pad is arranged on the surface of the substrate and is electrically connected to the substrate.
10. An electronic device, characterized in that, Comprising: The directional microphone according to any one of claims 1-9.