A bone-voiceprint sensor

Abstract

The application provides a bone voiceprint sensor, which comprises a first circuit board, a cavity formed in the lower surface of the first circuit board, a sound hole and an exhaust passage formed in the upper surface of the first circuit board, a vibration system arranged in the cavity, a support part, an elastic membrane arranged on the support part, and a mass arranged on the elastic membrane, wherein the elastic membrane divides the cavity into a first lower chamber and a second upper chamber, a second circuit board arranged below the first circuit board and sealing the cavity, a MEMS microphone assembly arranged on the upper surface of the first circuit board and communicating with the cavity through the sound hole, and a shell connected with the first circuit board and enclosing a containing cavity containing the MEMS microphone assembly, wherein the containing cavity communicates with the first chamber through the exhaust passage. The bone voiceprint sensor can improve the compact structure, improve the packaging integration, improve the sensitivity of the microphone, simplify the process, improve the reliability, and reduce the cost.

Description

Technical Field

[0001] This application belongs to the field of semiconductor technology and relates to a bone conduction sensor. Background Technology

[0002] A bone conduction sensor (VPU sensor) is a sensor that detects sound waves transmitted by vibrations in the human skeleton and converts the resulting vibration signals into electrical signals. It typically consists of a vibration system and a MEMS (Micro-Electro-Mechanical System) microphone assembly. The vibration system senses external vibrations, and the MEMS microphone assembly converts the resulting airflow changes into electrical signals to represent the vibration information. Both the vibration system and the MEMS microphone assembly are the core components of the bone conduction sensor.

[0003] Compared to traditional MEMS microphones, bone conduction sensors are unaffected by airborne noise, significantly improving speech recognition rates in noisy environments. Furthermore, because bone conduction sensors have no sound inlet, they are dustproof and waterproof, allowing them to be used in harsher environments. Utility Model Content

[0004] The main technical problem addressed by this application is to provide a bone conduction sensor with higher integration.

[0005] This application proposes a bone voiceprint sensor, comprising:

[0006] A first circuit board has a lower surface and an upper surface opposite to each other. A cavity is formed on the lower surface, and a sound hole and an exhaust channel are formed on the upper surface. The sound hole connects to the top of the cavity, and the exhaust channel connects to one side of the cavity.

[0007] A vibration system, disposed within the cavity, includes: a support portion, an elastic membrane disposed on the support portion, and a mass block disposed on the elastic membrane, wherein the elastic membrane and the support portion divide the cavity into a first chamber near the lower surface and a second chamber near the upper surface;

[0008] The second circuit board is disposed below the first circuit board and encloses the cavity;

[0009] A MEMS microphone assembly is disposed on the upper surface of the first circuit board and communicates with the cavity through the sound hole;

[0010] The housing is connected to the first circuit board and forms a cavity for accommodating the MEMS microphone assembly. The cavity is connected to the first chamber through the exhaust channel.

[0011] In some alternative embodiments, the width of the mass block in the cross-sectional direction is smaller than the width of the bottom of the cavity, and the width of the bottom of the cavity is smaller than the width of the cavity opening.

[0012] In some alternative embodiments, the mass block is disposed on the upper or lower surface of the elastic membrane.

[0013] In some alternative implementations, the width of the first circuit board and the width of the second circuit board are the same in the cross-sectional view.

[0014] In some alternative embodiments, a step is formed at the bottom edge of the cavity, and the support is disposed on the step.

[0015] In some alternative implementations, the MEMS microphone assembly includes a microphone MEMS chip and a microphone ASIC chip, wherein the microphone MEMS chip is disposed at the sound hole.

[0016] In some alternative implementations, the microphone MEMS chip and the microphone ASIC chip, and the microphone ASIC chip and the first circuit board, are electrically connected by bonding wires.

[0017] In some alternative implementations, the microphone MEMS chip and the microphone ASIC chip are respectively fixed to the first circuit board by adhesive.

[0018] In some alternative implementations, the housing is connected to the upper surface of the first circuit board via solder paste.

[0019] In some alternative implementations, the first circuit board and the second circuit board are connected by solder paste.

[0020] As described above, this application proposes a bone voiceprint sensor, which has the following advantages by adopting the above technical solution:

[0021] 1. The bone conduction sensor of this application can improve the compactness of the structure and increase the packaging integration by embedding the vibration system in the cavity of the first circuit board. Furthermore, a step can be set in the cavity to raise the vibration system, thereby increasing the vibration space of the vibration system, which helps to improve the sensitivity and enhance the vibration effect.

[0022] 2. The vibration system is located inside the cavity of the first circuit board, closer to the vibration source, which enables it to capture external vibration signals more efficiently and reduce the loss of vibration energy during transmission, thereby improving the sensitivity of the microphone and making applications such as voice recognition more accurate and clear.

[0023] 3. Setting up an exhaust channel connecting the cavity is beneficial to improving the vibration performance of the vibration system, without having to set exhaust holes on its mass block and elastic membrane.

[0024] 4. The vibration system, the first circuit board, and the second circuit board can be made into a subsystem, which can simplify the process and improve reliability.

[0025] 5. The casing can be a common structure casing, such as a casing made of metals like copper or aluminum, which is less expensive. Attached Figure Description

[0026] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments and the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a cross-sectional structural schematic diagram of a bone voiceprint sensor according to an embodiment of this application;

[0028] Figure 2 This is a cross-sectional structural schematic diagram of a bone voiceprint sensor proposed in another embodiment of this application. Detailed Implementation

[0029] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present application.

[0030] The terms "first," "second," "third," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or apparatuses.

[0031] The following detailed descriptions will be provided through specific embodiments.

[0032] refer to Figure 1One embodiment of this application discloses a bone voiceprint sensor, which includes:

[0033] The first circuit board 1 has a lower surface and an upper surface, the lower surface of which forms a cavity, and the upper surface forms a sound hole 4 and an exhaust channel 8. The sound hole 4 connects to the top of the cavity, and the exhaust channel connects to one side of the cavity.

[0034] The vibration system, disposed within the cavity, includes: a support 3, an elastic membrane 7 disposed on the support 3, and a mass block 5 disposed on the elastic membrane 7, wherein the elastic membrane 7 and the support 3 divide the cavity into a first chamber 61 near the lower surface and a second chamber 62 near the upper surface.

[0035] The second circuit board 2 is located below the first circuit board 1 and encloses the cavity;

[0036] The MEMS microphone assembly is disposed on the upper surface of the first circuit board 1 and is connected to the second chamber 62 through the sound hole 4;

[0037] The housing 12 is disposed on the upper surface of the first circuit board 1, and together with the first circuit board 1, forms a receiving cavity 63 for accommodating the MEMS microphone assembly. The receiving cavity 63 is connected to the first chamber 61 through the exhaust channel 8.

[0038] Here, the first circuit board 1 and the second circuit board 2 can be circuit boards with a circuit layer and a dielectric layer.

[0039] Here, by setting an exhaust channel 8 connecting the cavity, it is beneficial to improve the vibration performance of the vibration system, without having to set exhaust holes on the mass block 5 and elastic membrane 7 of the vibration system.

[0040] In some alternative embodiments, a step 101 is formed at the bottom edge of the cavity, and the support 3 is disposed on the step 101. By providing the step 101, the support 3 can be raised, thereby increasing the vibration space of the vibration system.

[0041] In some alternative implementations, the width of the mass block 5 in the cross-sectional direction is smaller than the width of the bottom of the cavity, and the width of the bottom of the cavity is smaller than the width of the cavity opening.

[0042] In some alternative embodiments, for example, the support 3 may be a metal ring, the elastic membrane 7 may be an elastic plastic film, and the mass block 5 may be a metal block or a non-metal block.

[0043] In some alternative implementations, the mass block 5 may be disposed on the upper or lower surface of the elastic membrane 7.

[0044] In some alternative implementations, the width of the first circuit board 1 and the width of the second circuit board 2 are the same in the cross-sectional view.

[0045] In some alternative implementations, the MEMS microphone assembly includes a microphone MEMS chip 11 and a microphone ASIC (Application Specific Integrated Circuit) chip 9, wherein the microphone MEMS chip 11 is disposed at the sound hole 5 and covers the sound hole 5.

[0046] In some optional embodiments, the microphone MEMS chip 11 and the microphone ASIC chip 9 are electrically connected via bonding wires 10, and the microphone ASIC chip 9 and the first circuit board 1 are also electrically connected via bonding wires 10. The bonding wires 10 can be metal wires such as gold wire, silver wire, copper wire, or aluminum wire, also known as wire bonding.

[0047] In some alternative implementations, the microphone MEMS chip 11 and the microphone ASIC chip 9 are respectively fixed to the first circuit board 1 by adhesive.

[0048] In some alternative embodiments, the housing 11 and the first circuit board 1 are connected by solder, such as solder paste.

[0049] In some alternative implementations, the first circuit board 1 and the second circuit board 2 are connected by solder paste.

[0050] The present application discloses a bone voiceprint sensor, the working principle of which is as follows: the vibration system detects external vibration signals and generates corresponding vibrations, thereby driving the gas flow in the cavity. The flowing gas causes the diaphragm of the microphone MEMS chip 11 to vibrate through the sound hole 4. The microphone MEMS chip 11 converts the variable vibration signal into a variable electrical signal, which is then amplified and output by the microphone ASIC chip 9.

[0051] refer to Figure 2 Another embodiment of this application proposes a bone voiceprint sensor. Figure 2 The bone voiceprint sensor shown is similar to Figure 1 The bone voiceprint sensor shown differs in that:

[0052] exist Figure 2 In the bone voiceprint sensor shown, no steps are set in the cavity on the first circuit board 1.

[0053] The technical solution of this application has been described in detail above through specific embodiments. In the above embodiments, the descriptions of each embodiment have their own emphasis, and for parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0054] It should be understood that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Those skilled in the art can modify the technical solutions described in the above embodiments, or make equivalent substitutions for some of the technical features; however, these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and protection scope of the technical solutions of the embodiments of this application.

Claims

1. A bone conduction sensor, characterized in that, include: A first circuit board has a lower surface and an upper surface opposite to each other. The lower surface forms a cavity, and the upper surface forms a sound hole and an exhaust channel. The sound hole connects to the top of the cavity, and the exhaust channel connects to one side of the cavity. A vibration system, disposed within the cavity, includes: a support portion, an elastic membrane disposed on the support portion, and a mass block disposed on the elastic membrane, wherein the elastic membrane and the support portion divide the cavity into a first chamber near the lower surface and a second chamber near the upper surface; The second circuit board is disposed below the first circuit board and encloses the cavity; A MEMS microphone assembly is disposed on the upper surface of the first circuit board and communicates with the cavity through the sound hole; The housing is connected to the first circuit board and forms a cavity for accommodating the MEMS microphone assembly. The cavity is connected to the first chamber through the exhaust channel.

2. The bone conduction sensor according to claim 1, characterized in that, In the cross-sectional view, the width of the mass block is less than the width of the bottom of the cavity, and the width of the bottom of the cavity is less than the width of the opening of the cavity.

3. The bone conduction sensor according to claim 1, characterized in that, The mass block is disposed on the upper or lower surface of the elastic membrane.

4. The bone conduction sensor according to claim 1, characterized in that, In cross-sectional view, the width of the first circuit board is the same as the width of the second circuit board.

5. The bone conduction sensor according to claim 4, characterized in that, The bottom edge of the cavity is stepped, and the support is disposed on the step.

6. The bone conduction sensor according to claim 1, characterized in that, The MEMS microphone assembly includes a microphone MEMS chip and a microphone ASIC chip, wherein the microphone MEMS chip is disposed at the sound hole.

7. The bone conduction sensor according to claim 6, characterized in that, The microphone MEMS chip and the microphone ASIC chip, and the microphone ASIC chip and the first circuit board are electrically connected by bonding wires.

8. The bone conduction sensor according to claim 6, characterized in that, The microphone MEMS chip and the microphone ASIC chip are respectively fixed to the first circuit board with adhesive.

9. The bone conduction sensor according to claim 1, characterized in that, The housing is connected to the upper surface of the first circuit board via solder paste.

10. The bone conduction sensor according to claim 1, characterized in that, The first circuit board and the second circuit board are connected by solder paste.

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