Loudspeaker module
By employing a dual MEMS speaker structure in the speaker module and using a circuit board to control the vibration of the speaker diaphragm in different directions, the problem of insufficient sound pressure in miniaturized speaker modules is solved, achieving higher sound pressure levels and flexible sound wave control.
Patent Information
- Application Number
- CN202423152691.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-19
- Publication Date
- 2025-12-23
- Estimated Expiration
- 2034-12-19
AI Technical Summary
Existing speaker modules cannot achieve both miniaturization and sufficient output power, resulting in insufficient sound pressure level and limited functionality.
The system employs a dual MEMS speaker structure, using a circuit board to control the diaphragm structure of the first and second MEMS speakers to achieve superposition or cancellation of vibrations in different directions, thereby improving sound pressure level performance.
Without compromising miniaturization, the sound pressure level performance of the loudspeaker is significantly improved through the superposition and cancellation technology of dual MEMS loudspeakers, enabling more flexible sound wave control.
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Figure CN223714163U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to acoustoelectricity technical field, especially a kind of loudspeaker module. BACKGROUND
[0002] Loudspeaker is a kind of transducer device for converting electrical signal into acoustic signal.The principle of action of loudspeaker is that audio power is converted into mechanical vibration by electromagnetic, piezoelectric or electrostatic effect, and the vibration of cone or diaphragm and the resonance with surrounding air produce sound.
[0003] Sound is formed by the wave change of air pressure, and loudspeaker pushes a certain amount of air to cause pressure change and thus emit a certain amount of sound (sound pressure).Based on the result of miniaturization, the current loudspeaker module usually sets one loudspeaker structure, and then controls the effective radius, frequency, distance and one-way stroke of the diaphragm in the loudspeaker structure to control the sound pressure.However, it meets the miniaturization but cannot simultaneously consider the output power, thus causing insufficient sound pressure and single function. SUMMARY
[0004] In view of the above problems, the main purpose of the utility model is to provide a loudspeaker module, which has two loudspeaker structures in the loudspeaker module without changing the existing miniaturization, and forms a loudspeaker module with higher sound pressure level by flexible control.
[0005] To achieve the above purpose, the technical scheme of the utility model provides a loudspeaker module, which comprises: a shell, the shell surrounds a cavity, and the shell has a sound outlet hole penetrating through the thickness of the shell; a circuit board located in the cavity, the circuit board has opposite first and second surfaces, the first surface has a first electrode connecting point, and the second surface has a second electrode connecting point; a first MEMS loudspeaker located in the cavity, the first MEMS loudspeaker is installed on the first surface in a flip-chip manner, the first MEMS loudspeaker comprises a first diaphragm structure, the first diaphragm structure is electrically connected with the first electrode connecting point, and the first diaphragm structure is controlled by the circuit board and generates vibration; and a second MEMS loudspeaker located in the cavity, the second MEMS loudspeaker is installed on the second surface in a flip-chip manner, the second MEMS loudspeaker comprises a second diaphragm structure, the second diaphragm structure is electrically connected with the second electrode connecting point, and the second diaphragm structure is controlled by the circuit board and generates vibration.
[0006] Preferably, the first MEMS loudspeaker further comprises: a first substrate surrounding a first cavity, the first diaphragm structure stacked above the first substrate and covering the first cavity, and a first flexible structure layer covering the first diaphragm structure; and the first diaphragm structure is a piezoelectric composite diaphragm.
[0007] Preferably, the second MEMS speaker further comprises: a second substrate surrounding a second cavity, the second diaphragm structure stacked above the second substrate and covering the second cavity, and a second flexible structure layer covering the second diaphragm structure; the second diaphragm structure is a piezoelectric composite diaphragm.
[0008] Preferably, the first diaphragm structure comprises a plurality of sub-diaphragms, and a gap is arranged between adjacent sub-diaphragms; the first flexible structure layer completely covers the gap.
[0009] Preferably, the bottom surface of the first substrate is a hexagonal three-dimensional structure, and the bottom surface of the first diaphragm structure is a hexagonal three-dimensional structure.
[0010] Preferably, the first diaphragm structure comprises six sub-diaphragms, the sub-diaphragms are polygonal structures extending from the edges of the first substrate to the center point of the first substrate, the top of the six polygonal structures is directed to the center point, and the bottom edge of each polygonal structure is located on the first substrate.
[0011] Preferably, the polygonal structure is a three-dimensional structure composed of isosceles triangles, and the vertex of the isosceles triangle is directed to the center point.
[0012] Preferably, the first flexible structure layer is an organic thin film layer.
[0013] Preferably, the first diaphragm structure comprises a support layer, a bottom electrode layer, a piezoelectric layer, a top electrode layer and a protective layer which are stacked; the support layer is arranged spaced apart from the first flexible structure layer.
[0014] Preferably, the circuit board has a through hole in the middle, and the through hole is square or circular in shape.
[0015] The loudspeaker module of the utility model is a bidirectional driving loudspeaker module, the first MEMS speaker and the second MEMS speaker on both sides of the circuit board can be driven by different driving signals, the vibration direction of the first diaphragm structure and the vibration direction of the second diaphragm structure are opposite at the same time, the sound waves generated by the first MEMS speaker and the second MEMS speaker are superimposed at the sound outlet, and the sound pressure level performance of the loudspeaker can be improved; secondly, the vibration direction of the first diaphragm structure and the vibration direction of the second diaphragm structure are the same at another time, the sound waves generated by the first MEMS speaker and the second MEMS speaker are cancelled at the sound outlet, and more flexible control is carried out. BRIEF DESCRIPTION OF DRAWINGS
[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed in the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained from these drawings without creative labor.
[0017] Figure 1 is a structural diagram of a loudspeaker module provided by the embodiment of the present application;
[0018] Figure 2 is Figure 1 is an exploded view of the loudspeaker module shown in
[0019] Figure 3 is Figure 1 is a sectional view of the loudspeaker module shown in
[0020] Figure 4 is Figure 1 is a structural diagram of a first MEMS loudspeaker in the loudspeaker module shown in
[0021] Figure 5 is Figure 1 is a sectional view of the first MEMS loudspeaker in the loudspeaker module shown in
[0022] Figure 6 is Figure 1 is a partial sectional view of a first diaphragm structure in the first MEMS loudspeaker shown in
[0023] Figure 7 is Figure 1 is a structural diagram of a second MEMS loudspeaker in the loudspeaker module shown in
[0024] Figure 8 is Figure 1 is a sectional view of the second MEMS loudspeaker in the loudspeaker module shown in DETAILED DESCRIPTION
[0025] In order to make the purpose, technical solutions and advantages of the embodiments of the present application more clear, the following will describe each embodiment of the present application in detail with reference to the drawings. However, those skilled in the art can understand that in the embodiments of the present application, many technical details are proposed in order to make the readers better understand the present application. However, even without these technical details and various changes and modifications based on the following embodiments, the technical solutions claimed by the present application can also be implemented.
[0026] In the embodiments of the present application, the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "transverse", "longitudinal" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. These terms are mainly used to better describe the present application and its embodiments, and are not intended to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation.
[0027] In addition, in addition to indicating the orientation or positional relationship, the above-mentioned terms may also be used to indicate other meanings, for example, the term "upper" may also be used to indicate a certain dependent relationship or connection relationship in some cases. For those skilled in the art, the specific meaning of these terms in the present application can be understood according to the specific circumstances.
[0028] In addition, the terms "mounting", "setting", "providing", "opening", "connecting", "connecting" should be broadly understood. For example, it can be fixedly connected, detachably connected, or integrally constructed; it can be mechanically connected, or electrically connected; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the internal communication between two devices, elements or components. For those skilled in the art, the specific meaning of the above-mentioned terms in the present application can be understood according to the specific circumstances.
[0029] In addition, the terms "first", "second" and the like are mainly used to distinguish different devices, elements or components (the specific types and structures may be the same or different), and are not intended to indicate or imply the relative importance and quantity of the indicated devices, elements or components. Unless otherwise stated, the meaning of "multiple" is two or more.
[0030] The embodiments of the present application will be described in detail below with reference to the accompanying drawings. However, those skilled in the art can understand that in the embodiments of the present application, many technical details are proposed in order to enable the reader to better understand the present application. However, even without these technical details and various changes and modifications based on the following embodiments, the technical solutions claimed in the present application can be realized.
[0031] Combined with reference Figures 1-8The utility model discloses an embodiment provides a kind of loudspeaker module, loudspeaker module includes: shell 10, shell 10 is enclosed cavity, shell 10 has the sound hole 102 of passing through the thickness of shell 10;Circuit board 110 located in cavity, circuit board 110 has opposite first face 111 and second face 112, first face 111 has first electrode connecting point 113, second face 112 has second electrode connecting point (not marked out);First MEMS (Micro-ElectroMechanical System, micro electro mechanical system) loudspeaker 150 located in cavity, first MEMS loudspeaker 150 is installed in first face 111 in flip-chip mode, first MEMS loudspeaker 150 includes first diaphragm structure 151, and first diaphragm structure 151 is electrically connected with first electrode connecting point 113, and first diaphragm structure 151 is controlled and generates vibration by circuit board 110;Second MEMS loudspeaker 160 located in cavity, second MEMS loudspeaker 160 is installed in second face 112 in flip-chip mode, and second MEMS loudspeaker 160 includes second diaphragm structure 161, and second diaphragm structure 161 is electrically connected with second electrode connecting point, and second diaphragm structure 161 is controlled and generates vibration by circuit board 110.
[0032] The shell 10 of the loudspeaker module is used to provide physical protection while minimizing the attenuation of the desired sound.
[0033] In combination with reference Figures 1-3 , shell 10 includes mutually engaging first shell 121 and second shell 122, and first shell 121 and second shell 122 form first sub-chamber 101 and second sub-chamber 103, and first sub-chamber 101 and second sub-chamber 103 together form the chamber.
[0034] The shell 10 has sound leakage holes (not shown) for balancing the pressure of the first sub-chamber 101 and the second sub-chamber 103 with the outside. The number and shape of the sound leakage holes are not limited by the utility model, and those skilled in the art can set the shape and number of the sound leakage holes according to actual needs.
[0035] The shell 10 has two opposite through holes, one of which serves as the sound hole 102, and the other as the connection end of the circuit board.
[0036] In one embodiment, the circuit board 110 can pass through the through hole on the shell as shown in Figure 1 , and the circuit board 110 has circuit connection points (such as first circuit connection points and second circuit connection points) on the surface of the circuit board 110, which are used to connect with circuit elements outside and transmit first signals and second signals. Among them, the first signal is used to control the vibration of the first diaphragm structure 151, and the second signal is used to control the vibration of the second diaphragm structure 161.
[0037] It should be noted that although Figure 1 The through hole in which the circuit board 110 is located is opposite to the sound hole 102 in the shell 10 shown, alternatively, the through hole in which the circuit board 110 is located can be on different sides of the shell 10 or other substrates that meet the design requirements.
[0038] Referring to Figure 2 The circuit board 110 provided by the embodiment has a through hole 115 in the middle, or the circuit board 110 is arranged in a ring shape, such as a square ring shape or a circular ring shape. The through hole 115 penetrates the thickness of the circuit board 110 and is opposite and penetrates the first cavity 154 of the first MEMS loudspeaker 150 and the second cavity 164 of the second MEMS loudspeaker 160, respectively. The through hole 115 can serve as a vibration space for the first diaphragm structure 151 and the second diaphragm structure 161.
[0039] The shape of the through hole 115 is polygonal or circular. Among them, the polygon can be square, triangular, hexagonal, octagonal or any shape.
[0040] The flip-chip mode refers to directly interconnecting the first MEMS loudspeaker 150 downward to the circuit board 110 through the bumps (third electrode connection points) on the first MEMS loudspeaker 150; and directly interconnecting the second MEMS loudspeaker 160 downward to the circuit board 110 through the bumps (fourth electrode connection points) on the second MEMS loudspeaker 160. By the flip-chip mode, the planar area size of the first MEMS loudspeaker 150 and the second MEMS loudspeaker 160 can be saved, thereby occupying less space and being smaller in size, saving space and realizing miniaturization.
[0041] Referring to Figure 4 The first MEMS loudspeaker 150 further includes a first substrate 153 surrounding the first cavity 154, a first diaphragm structure 151 stacked above the first substrate 153 and covering the first cavity 154, and a first flexible structure layer 157 covering the first diaphragm structure 151; the first diaphragm structure 151 is a piezoelectric composite diaphragm.
[0042] The bottom surface shape of the first substrate 153 of the first MEMS loudspeaker 150 can be circular, square, hexagonal, octagonal or any equilateral graph.
[0043] The bottom surface of the first substrate 153 of the first MEMS speaker 150 is a hexagonal three-dimensional structure, the first substrate 153 is arranged in a hexagonal ring shape, the first diaphragm structure 151 and the first substrate 153 form a first cavity 154, the first cavity 154 penetrates through the first substrate 153, and the first cavity 154 serves as a vibration space of the first MEMS speaker 150. Optionally, the first substrate 153 can be a single crystal silicon substrate or other substrates that meet the design requirements.
[0044] When the first substrate 153 is arranged in a hexagonal ring shape, the inner side and the outer side of the first substrate 153 are chamfered, especially circular chamfered, which can reduce the sharp structure inside the first MEMS speaker 150, which is beneficial to the assembly of the product, and can also avoid that the sharp structure on the first substrate 153 contacts and damages other internal devices of the first MEMS speaker 150.
[0045] The bottom surface of the first diaphragm structure 151 can be circular, square, hexagonal, octagonal, or any equilateral graph. The bottom surface of the first diaphragm structure 151 is a hexagonal three-dimensional structure corresponding to the shape of the first substrate 153.
[0046] Optionally, the first diaphragm structure 151 includes a plurality of sub-diaphragms 1511, and the adjacent sub-diaphragms 1511 have a slit 155. For example, the first diaphragm structure includes 4 sub-diaphragms, the first diaphragm structure includes 5 sub-diaphragms, or the first diaphragm structure includes 6 sub-diaphragms, etc. Of course, for those skilled in the art, other numbers of sub-diaphragms and other shapes of the first substrate can also be set according to actual needs.
[0047] The first diaphragm structure 151 includes six sub-diaphragms 1511, and the sub-diaphragm 1511 is a polygonal structure extending from the edge of the first substrate 153 to the center point of the first substrate 153. The top of the six polygonal structures is directed to the center point, and the bottom edge of each polygonal structure is located on the first substrate 153.
[0048] Reference Figure 4 And Figure 5 , the utility model takes the first diaphragm structure 151 includes six sub-diaphragms 1511 as an example. Each sub-diaphragm 1511 is a three-dimensional structure composed of an isosceles triangle, the top of the six isosceles triangles is directed to the center point of the first substrate 153 and surrounds a hexahedral structure, the bottom edge of each isosceles triangle is located on the first substrate 153, and the first cavity 154 formed by the first substrate 153 also has a hexahedral shape.
[0049] Optionally, referring to Figure 6 , the first diaphragm structure 151 includes a support layer 185, a bottom electrode layer 184, a piezoelectric layer 183, a top electrode layer 182 and a protective layer 181.
[0050] The material of the support layer 185 can be SOI (Silicon On Insulato).
[0051] The material of the bottom electrode layer 184 can be platinum.
[0052] The material of the piezoelectric layer 183 can be PZT (Lead Zirconate Titanate). The PZT thin film has a high piezoelectric constant, thereby improving the electromechanical conversion efficiency and the speaker driving speed.
[0053] The material of the top electrode layer 182 can be gold and platinum alloy. The material of the protective layer 182 can be silicon nitride.
[0054] Optionally, referring to Figure 5 , the first diaphragm structure 151 and the first substrate 153 further have an insulating layer 159 therebetween. The material of the insulating layer 159 is silicon dioxide, which can reduce the parasitic capacitance between the two compared with the structure without the insulating layer.
[0055] It should be noted that the sizes and shapes of the plurality of sub-diaphragms shown in the embodiment Figures 2 to 8 may be different according to actual needs.
[0056] The first diaphragm structure 151 and the circuit board 110 have an insulating glue 107 therebetween. The insulating glue 107 has a through hole, which can accommodate a first conductive metal layer 108. The first conductive metal layer 108 is used to connect the first electrode connecting point 113 of the circuit board 110 and a third electrode connecting point (not labeled) on the first diaphragm structure 151.
[0057] The material of the insulating glue 107 can be silicone. The material of the first conductive metal layer 108 can be conductive glue, such as silver glue.
[0058] Optionally, the first flexible structure layer 157 and the support layer 185 are arranged with a spacing therebetween, and the first diaphragm structure of the piezoelectric layer is arranged therebetween. The first flexible structure layer 157 is a complete sheet structure without a gap structure. The first flexible structure layer 157 completely covers the slit 155, so that the overall structure of the first MEMS speaker 150 does not have a fine gap, and the performance in the medium and high frequency will be more prominent.
[0059] The first flexible structure layer 157 includes at least one organic thin film layer. The Young's modulus of the first flexible structure layer 157 is less than the Young's modulus of the piezoelectric diaphragm. The Young's modulus of the first flexible structure layer 157 is 100 MPa to 50 GPa.
[0060] Reference Figure 7 and Figure 8 The second MEMS speaker 160 further comprises a second substrate 163 surrounding a second cavity 164, a second diaphragm structure 161 stacked above the second substrate 163 and covering the second cavity 164, and a second flexible structure layer 167 covering the second diaphragm structure 161. The second diaphragm structure 161 is a piezoelectric composite diaphragm.
[0061] The second diaphragm structure 161 comprises a plurality of second sub-diaphragms 1611, and the adjacent second sub-diaphragms 1611 have a second slit 165 therebetween. Each second sub-diaphragm 1611 is a three-dimensional structure composed of six isosceles triangles, and the six isosceles triangles have their vertices pointing to a center point of the second substrate 163 and surround a hexahedron structure, and each isosceles triangle has its base on the second substrate 163.
[0062] The second diaphragm structure 161 and the second substrate 163 further have a second insulating layer 169 therebetween. The second diaphragm structure 161 and the circuit board 110 have an insulating glue 107 therebetween, and the insulating glue 107 has a through hole for accommodating the second conductive metal layer 118, and the second conductive metal layer 118 is used for connecting a second electrode connecting point of the circuit board 110 and a fourth electrode connecting point 162 on the second diaphragm structure 161.
[0063] It should be noted that the second diaphragm structure 161, the fourth electrode connecting point 162, the second substrate 163 and the second flexible structure layer 167 in the second MEMS speaker 160 can refer to the description of the first diaphragm structure 151, the third electrode connecting point, the first substrate 153 and the first flexible structure layer 157 in the first MEMS speaker 150, which will not be described in detail here.
[0064] In one example, the first MEMS speaker and the second MEMS speaker have different structures. The structure of the first MEMS speaker is the first MEMS speaker 150 as described in the above embodiments, and the structure of the second MEMS speaker is a speaker known to those skilled in the art.
[0065] In another example, the first MEMS speaker and the second MEMS speaker have different structures. The structure of the second MEMS speaker is the second MEMS speaker 160 as described in the above embodiments, and the structure of the first MEMS speaker is a speaker known to those skilled in the art.
[0066] In yet another example, the first MEMS speaker 150 and the second MEMS speaker 160 have the same structure.
[0067] Based on the design of the first MEMS speaker 150 and the second MEMS speaker 160 in the speaker module, the first MEMS speaker 150 and the second MEMS speaker 160 can be simultaneously driven, so that the vibration direction of the first diaphragm structure 151 in the first MEMS speaker 150 is opposite to the vibration direction of the second diaphragm structure 161 in the second MEMS speaker 160, so that the sound waves generated by the first MEMS speaker 150 and the second MEMS speaker 160 are superimposed at the sound hole 102, thereby a higher sound pressure level can be generated, for example, 2dB-6dB sound pressure level.
[0068] When the first signal received by the first MEMS speaker 150 and the second signal of the second MEMS speaker 160 are controlled respectively, the corresponding electrical signals can drive the first MEMS speaker 150 and the second MEMS speaker 160 respectively, so that the vibration direction of the first diaphragm structure 151 is opposite to the vibration direction of the second diaphragm structure 161 in some frequency bands, and the sound waves are superimposed; in another frequency band, the vibration direction of the first diaphragm structure 151 is the same as the vibration direction of the second diaphragm structure 161, and the sound waves are cancelled, thereby more flexible control is performed.
[0069] It should be noted that in the above embodiments, only the features of the first MEMS speaker are described, and the features of the second MEMS speaker are not described in detail. The second MEMS speaker is the same as the first MEMS speaker, so the features of the second MEMS speaker can be referred to the features of the first MEMS speaker, which will not be described in detail here.
[0070] It can be understood by those skilled in the art that the above embodiments are specific embodiments for implementing the present application, and in actual application, various changes can be made in form and details without departing from the spirit and scope of the present application.
Claims
1. A speaker module, characterized by The application relates to a speaker comprising: a housing enclosing a cavity, the housing having a sound hole penetrating through the thickness of the housing; a circuit board located in the cavity, the circuit board having opposite first and second surfaces, the first surface having a first electrode connection point, and the second surface having a second electrode connection point; a first MEMS speaker located in the cavity, the first MEMS speaker being mounted on the first surface in a flip-chip manner, the first MEMS speaker comprising a first diaphragm structure, the first diaphragm structure being electrically connected to the first electrode connection point, and the first diaphragm structure being controlled by the circuit board and generating vibration; a second MEMS speaker located in the cavity, the second MEMS speaker being mounted on the second surface in a flip-chip manner, the second MEMS speaker comprising a second diaphragm structure, the second diaphragm structure being electrically connected to the second electrode connection point, and the second diaphragm structure being controlled by the circuit board and generating vibration.
2. The speaker module of claim 1, wherein, The first MEMS speaker further comprises a first substrate enclosing a first cavity, the first diaphragm structure being stacked above the first substrate and covering the first cavity, and a first flexible structure layer covering the first diaphragm structure; and the first diaphragm structure is a piezoelectric composite diaphragm.
3. The speaker module of claim 1 or 2, wherein, The second MEMS speaker further comprises a second substrate enclosing a second cavity, the second diaphragm structure being stacked above the second substrate and covering the second cavity, and a second flexible structure layer covering the second diaphragm structure; and the second diaphragm structure is a piezoelectric composite diaphragm.
4. The speaker module of claim 2, wherein, The first diaphragm structure comprises a plurality of sub-diaphragms, and adjacent sub-diaphragms are separated by a slit; and the first flexible structure layer completely covers the slit.
5. The speaker module of claim 4, wherein, The bottom surface of the first substrate is a hexagonal three-dimensional structure; and the bottom surface of the first diaphragm structure is a hexagonal three-dimensional structure.
6. The speaker module of claim 5, wherein, The first diaphragm structure comprises six sub-diaphragms, the sub-diaphragms being polygonal structures extending from the edges of the first substrate to the center point of the first substrate, the top portions of the six polygonal structures being directed towards the center point, and the bottom edges of each polygonal structure being located on the first substrate.
7. The speaker module of claim 6, wherein, The polygonal structure is a three-dimensional structure composed of isosceles triangles, and the top points of the isosceles triangles are directed towards the center point.
8. The speaker module of claim 2, wherein, The first flexible structure layer is an organic thin film layer.
9. The speaker module of claim 2, wherein, The first diaphragm structure comprises a support layer, a bottom electrode layer, a piezoelectric layer, a top electrode layer and a protective layer which are stacked in sequence; and the support layer is spaced apart from the first flexible structure layer.
10. The speaker module of claim 1, wherein, The circuit board has a through hole in the middle, and the through hole is polygonal or circular.