Bone conduction MEMS microphone structure

Abstract

The utility model relates to the technical field of acoustics, in particular to a bone conduction MEMS microphone structure. Comprising a first PCB, a second PCB and a third PCB, the upper end face of the second PCB is provided with an electro-acoustic conversion chip MEMS and an electric signal processing chip ASIC, the electro-acoustic conversion chip MEMS and the electric signal processing chip ASIC are connected through a gold wire, the lower end face of the second PCB is provided with a vibrating diaphragm assembly, and the first PCB, the second PCB and the third PCB are arranged in a stacked mode. Vibration is transmitted to the microphone through the skeleton, the vibrating diaphragm assembly starts to vibrate, so that the pressure in the cavity is changed, the changed pressure is transmitted to the vibrating diaphragm assembly, the vibrating diaphragm assembly vibrates, a vibration signal is converted into an electric signal through the electro-acoustic conversion chip MEMS, and the electric signal is amplified and processed by the electric signal processing chip ASIC and then output. According to the design, a mature packaging process is utilized, so that the production process of the bone conduction MEMS microphone is simpler, and the production efficiency is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of acoustics, and in particular to a bone conduction MEMS microphone structure. Background Art

[0002] Bone conduction microphones transmit sound signals by picking up the speaker's own bone vibrations and are widely used in the field of smart wearables.

[0003] However, the current bone conduction MEMS microphone has a relatively complex structure and is difficult to package. Utility Model Content

[0004] The purpose of the present invention is to provide a bone conduction MEMS microphone structure, aiming to solve the technical problems in the prior art that the bone conduction MEMS microphone structure is relatively complex and the packaging is difficult.

[0005] To achieve the above objectives, the present invention adopts a bone conduction MEMS microphone structure, including a first PCB board, a second PCB board, and a third PCB board. The upper end surface of the second PCB board is provided with an electroacoustic conversion chip MEMS and an electrical signal processing chip ASIC, and the electroacoustic conversion chip MEMS and the electrical signal processing chip ASIC are connected by gold wires. The lower end surface of the second PCB board is provided with a diaphragm assembly. The first PCB board and the second PCB board are bonded to each other and are located above the second PCB board. The second PCB board and the third PCB board are bonded to each other and are located above the third PCB board. The first, second, and third PCB boards are arranged in a stacked manner.

[0006] Wherein, a first air leakage hole is opened in the first PCB board.

[0007] A sound hole is provided in the second PCB board, a step is provided on the lower end surface of the second PCB board, and the diaphragm assembly is located in the step.

[0008] In which, the diaphragm assembly includes a support ring, a diaphragm and a mass block, the support ring is fixedly connected to the mass block and is sleeved on the outside of the mass block, the support ring is bonded to the second PCB board and is located on the lower end surface of the second PCB board, and the support ring, the diaphragm and the mass block are all located in the step, and the diaphragm is also located on the lower end surface of the mass block.

[0009] The bone conduction MEMS microphone structure further includes a PAD, which is bonded to the third PCB board and is located below the third PCB board.

[0010] Wherein, the PAD is a pad.

[0011] The second air release holes of the mass block and the center of the diaphragm are connected.

[0012] The utility model discloses a bone conduction MEMS microphone structure, including first PCB board, second PCB board and third PCB board, the upper end surface of second PCB board is provided with electro -acoustic conversion chip MEMS and electric signal processing chip ASIC, the electro -acoustic conversion chip MEMS with electric signal processing chip ASIC is connected through gold wire, the lower end surface of second PCB board is provided with diaphragm subassembly, first PCB board with second PCB board is bonded, and located the upper of second PCB board, second PCB board with third PCB board is bonded, and located the upper of third PCB board, and first PCB board, second PCB board and third PCB board are stacked and set, and when the wearer sounds, the vibration is passed to the microphone through the skeleton, and the diaphragm subassembly starts vibrating, thereby causing the pressure in the cavity to change, and the changing pressure is transmitted to the diaphragm subassembly, so that the diaphragm subassembly vibrates, and the vibration signal is converted into an electric signal through the electro -acoustic conversion chip MEMS, and then the electric signal is amplified and processed through the electric signal processing chip ASIC and output, the mature packaging process is used in the design, the production process of bone conduction MEMS microphone is simpler, and production efficiency is provided. BRIEF DESCRIPTION OF DRAWINGS

[0013] In order to more clearly illustrate the technical scheme in the embodiments of the utility model or the prior art, below will be to the drawings needed to be used in the embodiment or prior art description simple introduction, obviously, the drawings in the following description only some embodiments of the utility model, for those skilled in the art, under the premise of not paying creative labor, can also obtain other drawings according to these drawings.

[0014] Figure 1 It is the internal structure schematic diagram of the bone conduction MEMS microphone structure of the utility model.

[0015] 1-first PCB board, 2-second PCB board, 3-third PCB board, 4-electro -acoustic conversion chip MEMS, 5-electric signal processing chip ASIC, 6-gold wire, 7-first air release hole, 8-mass block, 9-diaphragm, 10-second air release hole, 11-PAD, 12-support ring. DETAILED DESCRIPTION

[0016] The following describes in detail embodiments of the present invention, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present invention, and should not be construed as limiting the present invention.

[0017] See also Figure 1 The present invention provides a bone conduction MEMS microphone structure, including a first PCB board 1, a second PCB board 2 and a third PCB board 3. The upper end surface of the second PCB board 2 is provided with an electroacoustic conversion chip MEMS 4 and an electrical signal processing chip ASIC 5. The electroacoustic conversion chip MEMS 4 and the electrical signal processing chip ASIC 5 are connected by a gold wire 6. The lower end surface of the second PCB board 2 is provided with a diaphragm assembly. The first PCB board 1 is bonded to the second PCB board 2 and is located above the second PCB board 2. The second PCB board 2 is bonded to the third PCB board 3 and is located above the third PCB board 3. The first PCB board 1, the second PCB board 2 and the third PCB board 3 are arranged in a stacked shape.

[0018] In this embodiment, when the wearer speaks, the vibration is transmitted to the microphone through the bones, and the diaphragm assembly begins to vibrate, thereby causing the pressure in the cavity to change. The changed pressure is transmitted to the diaphragm assembly, causing the diaphragm assembly to vibrate, and the vibration signal is converted into an electrical signal through the electroacoustic conversion chip MEMS4, and then amplified and processed by the electrical signal processing chip ASIC5 for output. This design utilizes mature packaging technology to make the production process of bone conduction MEMS microphones simpler and improve production efficiency.

[0019] Furthermore, a first air leakage hole 7 is provided in the first PCB board 1 .

[0020] In this embodiment, the first air vent hole 7 can facilitate the balance of the internal and external air pressures of the first PCB board 1, ensuring clear sound quality without noise.

[0021] Furthermore, a sound hole is opened in the second PCB board 2, and a step is provided on the lower end surface of the second PCB board 2, and the diaphragm assembly is located in the step.

[0022] In this embodiment, the sound hole can facilitate sound pickup, and the step helps to maintain airtightness and stability.

[0023] Further, the vibrating diaphragm assembly comprises a support ring 12, a vibrating diaphragm 9 and a mass block 8, the support ring 12 is fixedly connected with the mass block 8 and is sleeved outside the mass block 8, the support ring 12 is bonded with the second PCB board 2 and is located at the lower end surface of the second PCB board 2, and the support ring 12, the vibrating diaphragm 9 and the mass block 8 are all located in the step, and the vibrating diaphragm 9 is also located at the lower end surface of the mass block 8.

[0024] In the embodiment, the vibrating diaphragm 9 captures sound fluctuations and converts them into mechanical movements, when the sound wave reaches the vibrating diaphragm 9, it will move with the change of sound pressure, the movement is usually very small, but it is enough to cause the sensor connected with the vibrating diaphragm 9 to generate a changing electrical signal, a closed chamber can be formed between the mass block 8 and the vibrating diaphragm 9, which provides necessary support for the vibrating diaphragm 9 and limits the movement range of the vibrating diaphragm 9, so as to control the dynamic response of the microphone.

[0025] Further, the bone conduction MEMS microphone structure further comprises a PAD 11, the PAD 11 is bonded with the third PCB board 3 and is located below the third PCB board 3.

[0026] In the embodiment, the PAD 11 can facilitate reducing the strength of the input signal to protect the subsequent equipment from being damaged by the excessively high signal level, and also provides support and protection for the internal structure such as the chip and the lead wire.

[0027] Further, the PAD 11 is a solder pad.

[0028] Further, the mass block 8 and the vibrating diaphragm 9 are both provided with a second air vent 10 at the center, and the two second air vents 10 are communicated.

[0029] In the embodiment, the second air vent 10 can facilitate balancing the internal and external air pressures of the mass block 8 and the vibrating diaphragm 9, and ensures clear and noise-free sound quality.

[0030] In the embodiment, the vibrating diaphragm assembly is bonded in the step of the second PCB board 2, the electro-acoustic conversion chip MEMS 4 and the electrical signal processing chip ASIC 5 are bonded on the upper end surface of the second PCB board 2 and are electrically connected through the gold wire 6, and finally the first PCB board 1, the second PCB board 2 and the third PCB board 3 are combined in a stacking manner, so as to form a bone conduction microphone device, the design is simple, the packaging difficulty is small, and the production efficiency is improved and the production cost is reduced.

[0031] The above disclosure is only a preferred embodiment of the present invention, and certainly cannot be used to limit the scope of rights of the present invention. Ordinary technicians in this field can understand that all or part of the processes of the above embodiment and equivalent changes made in accordance with the claims of the present invention are still within the scope of the utility model.

Claims

1. A bone conduction MEMS microphone structure, characterized in that: The device comprises a first PCB board, a second PCB board, and a third PCB board. The upper end surface of the second PCB board is provided with an electroacoustic conversion chip MEMS and an electrical signal processing chip ASIC, and the electroacoustic conversion chip MEMS and the electrical signal processing chip ASIC are connected by gold wires. The lower end surface of the second PCB board is provided with a diaphragm assembly. The first PCB board is bonded to the second PCB board and is located above the second PCB board. The second PCB board is bonded to the third PCB board and is located above the third PCB board. The first, second, and third PCB boards are stacked.

2. The bone conduction MEMS microphone structure according to claim 1, wherein: A first air leakage hole is formed in the first PCB board.

3. The bone conduction MEMS microphone structure according to claim 2, wherein: A sound hole is provided in the second PCB board, a step is provided on the lower end surface of the second PCB board, and the diaphragm assembly is located in the step.

4. The bone conduction MEMS microphone structure according to claim 3, wherein: The diaphragm assembly includes a support ring, a diaphragm and a mass block. The support ring is fixedly connected to the mass block and is sleeved on the outside of the mass block. The support ring is bonded to the second PCB board and is located on the lower end surface of the second PCB board. The support ring, the diaphragm and the mass block are all located in the step, and the diaphragm is also located on the lower end surface of the mass block.

5. The bone conduction MEMS microphone structure according to claim 4, wherein: The bone conduction MEMS microphone structure further includes a PAD, which is bonded to the third PCB board and is located below the third PCB board.

6. The bone conduction MEMS microphone structure according to claim 5, wherein: The PAD is a solder pad.

7. The bone conduction MEMS microphone structure according to claim 6, wherein: A second air leakage hole is formed at the center of each of the mass block and the diaphragm, and the two second air leakage holes are connected.

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