Vibration sensor and electronic apparatus
By setting a capacitor on the vibration assembly of the bone soundprint sensor and setting a breathable channel in the package structure, combined with the design of setting the ASIC chip in the first substrate, the problem of performance degradation when the height is reduced is solved, and higher sensitivity and lower height are achieved.
Patent Information
- Application Number
- CN202421779733.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-25
- Publication Date
- 2025-05-27
- Estimated Expiration
- 2034-07-25
AI Technical Summary
Existing bone soundprint sensors cannot maintain product performance while reducing the height, which affects the product's sensitivity and signal-to-noise ratio.
Air damping is reduced by providing capacitors on the vibration assembly instead of the MEMS chip in the traditional bone sound sensor and setting breathable channels inside the package structure. In addition, the ASIC chip is arranged in the first substrate, further reducing the height of the product.
It realizes that the product's sensitivity performance is maintained or improved while reducing the product's height, and avoids adverse product losses due to MEMS foreign matter or rupture.
Smart Images
Figure CN222916151U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of sensors, and more specifically, to a vibration sensor and an electronic device. Background Art
[0002] A bone voiceprint sensor is a sensor that uses the vibration of a diaphragm to drive air flow and detects the flow signal accordingly. Traditional bone voiceprint sensors usually include a vibration component 2 and a microphone component. The microphone component includes a MEMS chip 3 and an ASIC chip 4. The vibration component 2 is used to sense external vibration information and squeeze / stretch the air between the diaphragm and the MEMS chip 3. The microphone component converts the air pressure change generated by the vibration of the vibration component 2 into an electrical signal to represent the vibration information.
[0003] Figure 1 Shows the specific structure of the existing bone voiceprint sensor. The vibration component 2 is mounted on the first substrate 5. The MEMS chip 3 and the ASIC chip 4 are arranged above the vibration component 2, and the metal shell 1 is fixed to the first substrate 5 through solder paste.
[0004] In Figure 1 In the structure of the bone voiceprint sensor shown, due to the stacked structure inside the structure, limited by this stacked structure, the height of the sensor cannot be made lower. The current designed height is 1.3 mm. While the height of the current ordinary silicon microphone is generally about 1 mm, making the VPU the main device affecting the structure stacking in the whole machine assembly. However, if the bone voiceprint sensor is reduced to a height of 1 mm on the basis of the current structure, it will inevitably lead to a series of problems such as the reduction of the back cavity of the product, thus affecting the performance of the product such as sensitivity / signal-to-noise ratio SNR. Summary of the Utility Model
[0005] In view of the above problems, the purpose of the present utility model is to provide a vibration sensor and an electronic device to solve the problem that the existing bone voiceprint sensor cannot maintain the product performance while reducing the height.
[0006] A vibration sensor provided by the present utility model includes a packaging structure composed of a first substrate and a metal shell. Among them, a vibration component is arranged on the first substrate inside the packaging structure. Among them,
[0007] A second substrate is arranged above the vibration component. A capacitor is arranged between the vibration component and the second substrate. And a first air permeable channel for reducing the air damping between the vibration component and the first substrate is arranged at the position where the vibration component is fixed to the first substrate.
[0008] In addition, a preferred structure is that the vibration assembly includes a vibration ring disposed on the first substrate, an elastic diaphragm disposed on the vibration ring, and a mass block disposed on a surface of the elastic diaphragm facing the first substrate, wherein the mass block drives the elastic diaphragm to vibrate up and down.
[0009] In addition, a preferred structure is that the vibration ring is fixed to the first substrate by an adhesive except for both ends thereof, and a first air permeation channel is formed between both ends of the vibration ring and the first substrate.
[0010] In addition, a preferred structure is that the capacitor includes a first electrode plate and a second electrode plate disposed corresponding to the first electrode plate, wherein,
[0011] The first electrode plate is disposed on a surface of the elastic diaphragm facing away from the first substrate, and the second electrode plate is disposed on a surface of the second substrate facing the first electrode plate.
[0012] In addition, a preferred structure is that a second air permeation channel is formed through the first electrode plate, the elastic diaphragm, and the mass block, and a third air permeation channel is formed through the second electrode plate and the second substrate, wherein,
[0013] The second air permeation channel and the third air permeation channel are used to reduce air damping between the first electrode plate and the second electrode plate.
[0014] In addition, a preferred structure is that an ASIC chip is disposed above the second substrate, and the ASIC chip is electrically connected to the first substrate and the second substrate respectively.
[0015] In addition, a preferred structure is that the ASIC chip is electrically connected to the first substrate and the second substrate respectively through gold wires, and a protective shielding layer is disposed to wrap the ASIC chip, wherein,
[0016] The protective shielding layer is a metal protective shielding layer.
[0017] In addition, a preferred structure is that the ASIC chip is electrically connected to the first substrate through a gold wire and is electrically connected to the second substrate through chip flip-chip.
[0018] In addition, a preferred structure is that an ASIC chip is buried inside the first substrate, and the ASIC chip is electrically connected to the capacitor and an external circuit through an RDL method.
[0019] In addition, a preferred structure is that the metal housing is fixed to the first substrate by an adhesive, wherein,
[0020] The adhesive is silver paste or solder paste.
[0021] In addition, a preferred structure is that the metal housing includes a top and side walls connected to the top, and the side walls are fixed to the first substrate, where
[0022] Sound holes communicating with the outside are provided on the top.
[0023] In addition, a preferred structure is that external pads are provided on the first substrate outside the encapsulation structure, and the first substrate is electrically connected to external devices through the external pads.
[0024] The present utility model also provides an electronic device, including the above-mentioned vibration sensor.
[0025] As can be seen from the above technical solutions, for the vibration sensor and the electronic device provided by the present utility model, by providing a capacitor on the vibration assembly to replace the MEMS chip in the traditional bone sound sensor, the height of the product is reduced, and the product quality loss caused by problems such as MEMS foreign objects and breakage is avoided; the air-permeable channels provided inside the encapsulation structure can improve the sensitivity performance of the product; in addition, by arranging the ASIC chip inside the first substrate, the height of the product is further reduced. Description of the Drawings
[0026] By referring to the following description in conjunction with the drawings, and with a more comprehensive understanding of the present utility model, other objects and results of the present utility model will become clearer and easier to understand. In the drawings:
[0027] Figure 1 Schematic diagram of an existing bone voiceprint sensor;
[0028] Figure 2 Schematic diagram of the vibration sensor according to Embodiment 1 of the present utility model;
[0029] Figure 3 Schematic diagram of the vibration sensor according to Embodiment 2 of the present utility model.
[0030] The reference numerals therein include: 1, metal housing; 2, vibration assembly; 3, MEMS chip; 4, ASIC chip; 5, first substrate; 6, second substrate; 7, first electrode plate; 8, second electrode plate; 9, first air-permeable channel; 10, second air-permeable channel; 11, third air-permeable channel; 12, sound hole; 21, elastic diaphragm; 22, mass block; 23, vibration ring.
[0031] In all the drawings, the same reference numerals indicate similar or corresponding features or functions. Detailed Embodiments
[0032] In the following description, for purposes of illustration, in order to provide a thorough understanding of one or more embodiments, numerous specific details are set forth. However, it is apparent that these embodiments may be practiced without these specific details. In other instances, well-known structures and devices are shown in block diagram form in order to facilitate describing one or more embodiments.
[0033] In the description of the present utility model, it should be understood that the orientation or positional relationships indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present utility model.
[0034] Aiming at the problem of the existing bone voiceprint sensor proposed above of reducing the height while maintaining the performance, the present utility model provides a vibration sensor and an electronic device.
[0035] The following will describe in detail the specific embodiments of the present utility model with reference to the drawings.
[0036] In order to illustrate the structure of the vibration sensor provided by the present utility model, Figures 2 to 3 The structure of the vibration sensor is exemplarily marked from different angles. Specifically, Figure 2 The structure of the vibration sensor according to Embodiment 1 of the present utility model is shown; Figure 3 The structure of the vibration sensor according to Embodiment 2 of the present utility model is shown.
[0037] As Figure 2 and Figure 3 collectively show, the vibration sensor provided by the present utility model includes a packaging structure composed of a first substrate 5 and a metal housing 1. Among them, a vibration component 2 is provided on the first substrate 5 inside the packaging structure. Among them, a second substrate 6 is provided above the vibration component 2, a capacitor is provided between the vibration component 2 and the second substrate 6, and a first air-permeable channel 9 for reducing the air damping between the vibration component 2 and the first substrate 5 is provided at the position where the vibration component 2 is fixed to the first substrate 5.
[0038] In an embodiment of the present utility model, the vibration assembly 2 includes a vibration ring 23 disposed on the first substrate 5, an elastic diaphragm 21 disposed on the vibration ring 23, and a mass block 22 disposed on a surface of the elastic diaphragm 21 facing the first substrate 5. Among them, the mass block 22 drives the elastic diaphragm 21 to vibrate up and down. That is to say, the mass block 22 is disposed on the surface of the elastic diaphragm 21 facing the first substrate 5, which can provide the sensitivity of the product.
[0039] Among them, except for the two end portions, the vibration ring 23 is fixed to the first substrate 5 through an adhesive, and a first air permeation channel 9 is formed between the two end portions of the vibration ring 23 and the first substrate 5. The purpose of setting the first air permeation channel 9 is to reduce the air damping between the mass block 22 and the first substrate 5 during vibration and improve the product sensitivity.
[0040] In an embodiment of the present utility model, the capacitor includes a first electrode plate 7 and a second electrode plate 8 disposed corresponding to the first electrode plate 7. Among them, the first electrode plate 7 is disposed on a surface of the elastic diaphragm 21 facing away from the first substrate 5, and the second electrode plate 8 is disposed on a surface of the second substrate 6 facing the first electrode plate 7.
[0041] Among them, a second air permeation channel 10 is formed through the first electrode plate 7, the elastic diaphragm 21, and the mass block 22, and a third air permeation channel 11 is formed through the second electrode plate 8 and the second substrate 6. Among them, the second air permeation channel 10 and the third air permeation channel 11 are used to reduce the air damping between the first electrode plate 7 and the second electrode plate 8.
[0042] The first electrode plate 7, the second electrode plate 8, and the gap between the two electrode plates form a capacitor. Among them, the second electrode plate 8 is a fixed electrode plate, and the first electrode plate 7 at the other end is a movable electrode plate. And air permeation channels are respectively disposed on the fixed electrode plate and the movable electrode plate, namely: the second air permeation channel 10 of the first electrode plate 7 and the third air permeation channel 11 of the second electrode plate 8. The purpose of setting the two air permeation channels is: when receiving a vibration excitation such that the mass block 22, the elastic diaphragm 21, and the first electrode plate vibrate up and down, to reduce the air damping between the two electrode plates (the first electrode plate 7 and the second electrode plate 8), thereby further improving the sensitivity of the product.
[0043] In an embodiment of the present utility model, the vibration sensor further includes an ASIC chip. The functions of the ASIC chip are mainly twofold. First, it provides an initial DC voltage to the capacitor. Vbias (initial voltage) is connected to the movable electrode plate (the first electrode plate 7) to provide the initial sensitivity of the product. Second, it reads the output voltage value of the capacitor. Vin (input voltage) is connected to the fixed electrode plate (the second electrode plate 8) and is output after being processed.
[0044] In an embodiment of the present utility model, the main working principle of the vibration sensor is as follows: When the product is subjected to vibration excitation, the mass block 22 drives the elastic diaphragm 21 to move up and down, thereby changing the distance between the two electrode plates (the first electrode plate 7 and the second electrode plate 8), and thus changing the capacitance C value of the capacitor. Since the initial voltage Vbias provided by the ASIC chip 4 is a fixed value, that is, the charging charge Q remains unchanged, the voltage between the first electrode plate 7 and the second electrode plate 8 changes by △U. This voltage signal is read by the ASIC chip 4 and then output.
[0045] In an embodiment of the present utility model, when the ASIC chip 4 is set at different positions, it has different effects on the height of the product. For details, please refer to Figure 2 and Figure 3 .
[0046] In Figure 2 shown in Embodiment 1, the ASIC chip 4 is arranged above the second substrate 6 inside the packaging structure; in Figure 3 shown in Embodiment 2, the ASIC chip 4 is arranged inside the first substrate 5. The following will respectively introduce in detail the specific structures of the positions where the ASIC chip is arranged.
[0047] As Figure 2 shown in Embodiment 1, an ASIC chip 4 is arranged above the second substrate 6, and the ASIC chip 4 is electrically connected to the first substrate 5 and the second substrate 6 respectively. Among them, the ASIC chip 4 is electrically connected to the first substrate 5 and the second substrate 6 through gold wires respectively, and a protective shielding layer is wrapped on the ASIC chip 4, where the protective shielding layer is a metal protective shielding layer. Or, the ASIC chip 4 is electrically connected to the first substrate 5 through a gold wire and is electrically connected to the second substrate 6 through chip flip-chip. In specific applications, a suitable electrical connection method can be selected according to the actual situation, and it is not limited to a certain fixed electrical connection method.
[0048] Figure 2 The height of the vibration sensor formed by the position where the ASIC chip 4 is arranged in
[0049] In order to Figure 2 Based on the embodiment 1 shown in the figure, the height of the product is further reduced. Figure 3 As shown, an ASIC chip 4 is embedded in the first substrate 5, and the ASIC chip 4 is electrically connected to the capacitor and the external circuit through RDL. RDL is a rewiring technology process, which is a key process for integrated circuit manufacturing. RDL rewiring technology refers to the process of forming a layer of metal lines on the chip surface during chip manufacturing to connect different functional modules on the chip. Figure 3 In the embodiment shown, since there is no influence of the arc height of the bonding wires of the ASIC chip 4, the overall height of the product can be reduced by more than 50%.
[0050] In addition, in an embodiment of the utility model, the metal shell 1 is fixed to the first substrate 5 by an adhesive, wherein the adhesive is silver paste or solder paste or silicone or epoxy glue. In a specific application, the specific adhesive is selected according to the actual situation and is not limited to a certain one. The metal shell 1 includes a top and a side wall connected to the top, and the side wall is fixed to the first substrate 5, wherein a sound hole 12 connected to the outside is provided on the top. An external solder pad is provided on the first substrate 5 outside the packaging structure, and the first substrate 5 is electrically connected to an external device through the external solder pad.
[0051] The utility model also provides an electronic device, which includes the above-mentioned vibration sensor. The specific structure of the vibration sensor refers to the above-mentioned embodiment. Since the electronic device adopts all the technical solutions of all the above-mentioned embodiments, it at least has all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be described one by one here.
[0052] It can be seen from the above embodiments that the vibration sensor and electronic device provided by the utility model reduce the height of the product and avoid product defects caused by MEMS foreign matter, cracks and other problems by arranging a capacitor on the vibration component to replace the MEMS chip in the traditional bone sound sensor; the air permeable channel arranged inside the packaging structure can improve the sensitivity performance of the product; in addition, the ASIC chip is arranged in the first substrate, which further reduces the height of the product.
[0053] The vibration sensor and the electronic device according to the present invention are described as examples with reference to the accompanying drawings. However, it should be understood by those skilled in the art that various improvements can be made to the vibration sensor and the electronic device according to the present invention without departing from the content of the present invention. Therefore, the protection scope of the present invention should be determined by the content of the attached claims.
Claims
1. A vibration sensor, comprising a packaging structure consisting of a first substrate and a metal shell, wherein: A vibration component is arranged on the first substrate inside the packaging structure, characterized in that: A second substrate is arranged above the vibration component, a capacitor is arranged between the vibration component and the second substrate, and a first air permeable channel for reducing air damping between the vibration component and the first substrate is arranged at a position where the vibration component and the first substrate are fixed.
2. The vibration sensor according to claim 1, characterized in that The vibration assembly includes a vibration ring arranged on the first substrate, an elastic diaphragm arranged on the vibration ring, and a mass block arranged on a side of the elastic diaphragm facing the first substrate, wherein the mass block drives the elastic diaphragm to vibrate up and down.
3. The vibration sensor according to claim 2, characterized in that The vibration ring is fixed to the first substrate by an adhesive except for the two ends, and the first air permeable channel is formed between the two ends of the vibration ring and the first substrate.
4. The vibration sensor according to claim 2, characterized in that The capacitor includes a first electrode plate and a second electrode plate arranged corresponding to the first electrode plate, wherein: The first electrode plate is arranged on a side of the elastic membrane away from the first substrate, and the second electrode plate is arranged on a side of the second substrate facing the first electrode plate.
5. The vibration sensor according to claim 4, characterized in that A second air permeable channel is provided through the first electrode plate, the elastic membrane, and the mass block, and a third air permeable channel is provided through the second electrode plate and the second substrate, wherein: The second air permeable channel and the third air permeable channel are used to reduce air damping between the first electrode plate and the second electrode plate.
6. The vibration sensor according to claim 1, characterized in that An ASIC chip is disposed above the second substrate, and the ASIC chip is electrically connected to the first substrate and the second substrate respectively.
7. The vibration sensor according to claim 6, characterized in that The ASIC chip is electrically connected to the first substrate and the second substrate respectively through gold wires, and a protective shielding layer is wrapped around the ASIC chip, wherein: The protective shielding layer is a metal protective shielding layer.
8. The vibration sensor according to claim 6, characterized in that The ASIC chip is electrically connected to the first substrate via gold wires and to the second substrate via chip flipping.
9. The vibration sensor according to claim 1, characterized in that: An ASIC chip is embedded in the first substrate, and the ASIC chip is electrically connected to the capacitor and an external circuit through an RDL method.
10. The vibration sensor according to claim 1, wherein: The metal housing is fixed to the first substrate by an adhesive, wherein: The adhesive is silver paste or solder paste.
11. The vibration sensor according to claim 10, characterized in that The metal housing includes a top and a side wall connected to the top, and the side wall is fixed to the first substrate, wherein: A sound hole communicating with the outside is arranged on the top.
12. The vibration sensor according to claim 1, wherein: An external pad is provided on the first substrate outside the packaging structure, and the first substrate is electrically connected to an external device through the external pad.
13. An electronic device, characterized in that: The invention comprises a vibration sensor as claimed in any one of claims 1 to 12.