Method for manufacturing pressure sensing module and pressure sensing module

Abstract

The application is suitable for the technical field of printed circuit board, and provides a manufacturing method of a pressure sensing module, comprising the following steps: providing a flexible circuit board and a sub-board, a circuit board unit is arranged on the surface of the flexible circuit board, and a solder pad is arranged in the circuit board unit; an auxiliary film is arranged on the surface of the flexible circuit board, the auxiliary film covers at least part of the circuit board unit and exposes the solder pad; a conductive adhesive material is arranged on the solder pad or at a position corresponding to the solder pad on the sub-board; the sub-board is attached to the circuit board unit, the auxiliary film is arranged between the sub-board and the circuit board unit, and the conductive adhesive material is used to bond the sub-board and the solder pad; and the auxiliary film is removed to obtain the pressure sensing module, and a gap is formed between the sub-board and the circuit board unit. The application also provides a pressure sensing module. The pressure sensing module and the manufacturing method thereof can solve the problem that the height value of the gap in the pressure sensing module is not easy to control.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of printed wiring board manufacturing, in particular to a manufacturing method of a pressure sensing module and the pressure sensing module. BACKGROUND

[0002] The pressure sensing module applied to a True Wireless Stereo (TWS) earphone has a pressure sensing principle that a slight change in a gap height value between modules occurs due to external pressure, and then a capacitance value changes, a signal is transmitted to a chip, and corresponding operations are performed after operation, so as to realize pressure sensing and interactive control, thereby achieving the purpose of controlling the earphone. The pressure sensing module is composed of a sub-board and a Flexible Printed Circuit (FPC), and the gap height value between the two becomes a core control point of the module product.

[0003] At present, the sub-board is usually welded on the FPC by SMT (Surface Mount Technology) process, and the gap between the two is controlled by the thickness of solder paste at both ends. However, the solder paste must be melted in the SMT reflow soldering process, in which case it is difficult to control the consistency of the height of the soldering points at both ends, and thus it is difficult to control the gap height value in the pressure sensing module, affecting the performance of the product. SUMMARY

[0004] Therefore, the present application provides a manufacturing method of a pressure sensing module and the pressure sensing module, which can solve the problem that the gap height value in the pressure sensing module is not easy to control.

[0005] An embodiment of the first aspect of the present application provides a manufacturing method of a pressure sensing module, comprising: providing a flexible printed circuit board and a sub-board, the board surface of the flexible printed circuit board being provided with a circuit board unit, and the circuit board unit being provided with a solder pad;

[0006] An auxiliary film is attached to the board surface of the flexible printed circuit board, the auxiliary film covering at least part of the circuit board unit and exposing the solder pad;

[0007] A conductive adhesive material is arranged on the solder pad or at a position corresponding to the solder pad of the sub-board;

[0008] The sub-board is attached to the circuit board unit, wherein the auxiliary film is located between the sub-board and the circuit board unit, and the conductive adhesive material adheres the sub-board and the solder pad;

[0009] The auxiliary film is removed to obtain a pressure sensing module, wherein a gap is formed between the sub-board and the circuit board unit.

[0010] In an embodiment, the thickness of the auxiliary film is equal to the preset height of the gap.

[0011] In an embodiment, the flexible circuit board comprises a circuit area and a board edge area outside the circuit area, and a plurality of circuit board units are arranged in the circuit area; the auxiliary film is arranged on the surfaces of the plurality of circuit board units.

[0012] In an embodiment, before the auxiliary film is arranged on the surface of the flexible circuit board, the manufacturing method further comprises: cutting the auxiliary film according to the size of the flexible circuit board to form a plurality of windowed portions in the auxiliary film, the windowed portions being used to expose the pads.

[0013] In an embodiment, one windowed portion of the auxiliary film is arranged in the middle of the auxiliary film and exposes the pads of the plurality of circuit board units.

[0014] In an embodiment, a plurality of auxiliary films are arranged at intervals, each of the auxiliary films corresponds to a row of circuit board units and extends between two rows of pads, and the width of the auxiliary film is less than or equal to the distance between two pads.

[0015] In an embodiment, at least one end of the auxiliary film is a sticking portion, and the auxiliary film is stuck to the board edge area through the sticking portion.

[0016] In an embodiment, the removing of the auxiliary film comprises:

[0017] cutting the sticking portion of the auxiliary film on the flexible circuit board, and then pulling out the auxiliary film from one side of the flexible circuit board; or,

[0018] peeling the sticking portion from the board edge area, and then pulling out the auxiliary film from one side of the flexible circuit board.

[0019] In an embodiment, the conductive adhesive material is conductive glue, and the attaching of the sub-boards to the circuit board units comprises: using an automatic reinforcement machine to attach the sub-boards to the circuit board units, and then using a vacuum pressing machine to press the sub-boards and the circuit board units; or,

[0020] the conductive adhesive material is tin paste, and the attaching of the sub-boards to the flexible circuit board comprises: using an automatic chip mounter to attach the sub-boards to the circuit board units, and then performing reflow soldering.

[0021] Embodiments of the second aspect of the present application propose a pressure sensing module manufactured by the manufacturing method of the pressure sensing module as described in the first aspect.

[0022] The manufacturing method of the pressure sensing module sets the auxiliary film on the flexible circuit board before the sub-plate is attached, so that the auxiliary film is located in the gap between the flexible circuit board and the sub-plate in the attachment step, and the stability of the gap height value is ensured; the auxiliary film can support the sub-plate, and can support and disperse the pressure during attachment, thereby reducing the deformation and warping of the sub-plate during attachment, and ensuring that the height values of each part of the same gap are equal and constant. Therefore, the setting of the auxiliary film improves the stability and uniformity of the gap, and the manufacturing method can obtain a pressure sensing module with good gap consistency, and avoid the difference in gap height values of the same type of module product. Therefore, the manufacturing method provided by the application can solve the problem that the gap height value of the pressure sensing module is not easy to control.

[0023] In addition, the auxiliary film has good processability, and can be attached to the whole board at one time, without the need to attach each circuit board unit one by one, and the production efficiency is high; the auxiliary film is flexible like the flexible circuit board, and will not cause damage to the sub-plate when the auxiliary film is attached and removed, and can be directly separated when removed, which is simple to operate and has high manufacturing efficiency.

[0024] The pressure sensing module provided by the application has good gap consistency and good capacitance consistency, and has good performance. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative labor.

[0026] Figure 1 is a flow chart of the manufacturing method of the pressure sensing module provided by an embodiment of the application;

[0027] Figure 2 is a structural schematic diagram of the flexible circuit board in the pressure sensing module provided by an embodiment of the application;

[0028] Figure 3 is a structural schematic diagram of the auxiliary film provided by an embodiment of the application;

[0029] Figure 4 is a structural schematic diagram of the flexible circuit board and the auxiliary film provided by an embodiment of the application;

[0030] Figure 5 is a structural schematic diagram of the pressure sensing module in the manufacturing process provided by an embodiment of the application;

[0031] Figure 6 is a structural schematic diagram of the flexible circuit board and the auxiliary film provided by another embodiment of the application.

[0032] The meanings of the labels in the figures are as follows:

[0033] 100, pressure sensing module; 10, flexible circuit board; 11, solder pad; 12, reinforcing sheet; 101, circuit area; 111, circuit board unit; 102, board edge area; 20, sub-board; 30, conductive adhesive material; 40, auxiliary film; 41, windowed portion; 42, adhesive portion. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and should not be used to limit the present application.

[0035] It should be noted that when a component is referred to as "fixed to" or "disposed on" another component, it can be directly or indirectly on the other component. When a component is referred to as "connected to" another component, it can be directly or indirectly connected to the other component. The terms "first", "second" are only used for the purpose of convenient description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features. The meaning of "a plurality of" is two or more, unless otherwise specifically limited.

[0036] It should also be noted that the same reference signs in the embodiments of the present application represent the same component or the same part, and for the same parts in the embodiments of the present application, only one part or component may be labeled with a reference sign in the drawings, and it should be understood that the reference sign is also applicable to other identical parts or components.

[0037] In order to illustrate the technical solutions of the present application, the following will be described with reference to specific drawings and embodiments.

[0038] The embodiments of the first aspect of the present application propose a manufacturing method of a pressure sensing module. Please refer to Figure 1 The manufacturing method of the pressure sensing module comprises:

[0039] Step S110: providing a flexible circuit board and a sub-board.

[0040] Please refer to Figures 2 to 5 , Figure 5 (a) of Figure 2A cross-sectional view of the flexible circuit board 10 along the line A-A is shown. The board surface of the flexible circuit board 10 is provided with a circuit board unit 111, and the circuit board unit 111 is provided with pads 11 for fixing and electrically connecting the sub-board 20. It can be understood that the number of pads 11 can be two, but is not limited thereto. The flexible circuit board 10 has been processed by one or more process flows of the processes of cutting, drilling, black hole, VCP plating, pattern transfer, AOI detection, lamination / pressing of a cover film, solder mask, punching, surface treatment, character, testing, punching, reinforcement lamination, and the like. Optionally, the side of the flexible circuit board 10 away from the pads 11 is provided with a reinforcing sheet 12, which can be a steel sheet or a plate of epoxy resin material (FR4 type).

[0041] The sub-board can be a steel sheet or a printed circuit board (PCB). If the sub-board 20 is a steel sheet, a steel sheet of a designed size can be directly provided; if the sub-board is a PCB, the PCB is made in advance according to a preset circuit pattern, and the PCB is provided with pads (not shown in the figure) corresponding to the pads 11. It can be understood that the PCB is also provided with a circuit for conducting or transmitting signals, but is not limited thereto.

[0042] Step S120: An auxiliary film 40 is attached to the board surface of the flexible circuit board 10, and the auxiliary film 40 covers at least part of the circuit board unit 111 and exposes the pads 11.

[0043] Please refer to Figures 3 to 5 , Figure 5 (b) is Figure 4 A cross-sectional view along the line B-B. The auxiliary film 40 covers at least part of the circuit board unit 111 and exposes the pads 11, and the auxiliary film 40 is used to be clamped between the sub-board 20 and the flexible circuit board 10 in the subsequent mounting step. The auxiliary film 40 is located between at least two pads 11, i.e., corresponding to the gap position to be formed.

[0044] The auxiliary film 40 can be a high-temperature-resistant film, such as a Polymide (PI) film, but is not limited thereto.

[0045] Optionally, the flexible circuit board 10 after the auxiliary film 40 is attached is subjected to plasma treatment, and the flexible circuit board 10 is cleaned, especially the pads on the flexible circuit board 10.

[0046] Step S130: A conductive adhesive material 30 is provided on the pads 11 or at the positions of the pads 11 on the sub-board 20.

[0047] The conductive adhesive material 30 can be solder paste or conductive adhesive. For example, if the sub-board 20 is a steel sheet, the conductive adhesive material 30 can be solder paste applied to the pads 11 or conductive adhesive applied to the corresponding pads 11 on the steel sheet; or if the sub-board 20 is a PCB, the conductive adhesive material 30 can be applied to the pads 11 of the circuit board unit 111 or the pads of the PCB, and the conductive adhesive material 30 can be solder paste or conductive adhesive.

[0048] It is understood that conductive adhesive material 30 is not limited to solder paste and conductive glue, but can also be other conductive and adhesive materials.

[0049] It is understandable that the order of steps S120 and S130 can be reversed.

[0050] Step S140: Mount the daughterboard 20 onto the circuit board unit 111.

[0051] Specifically, the sub-board 20 is mounted on the circuit board unit 111. Conductive adhesive material 30 is used to bond the sub-board 20 to the pads 11. The conductive adhesive material 30 is used to fix the sub-board 20 and to achieve conductivity. During mounting, an auxiliary film 40 is located between the sub-board 20 and the circuit board unit 111. The auxiliary film 40 fills the gap between the sub-board 20 and the flexible circuit board 10 between the two pads 11, serving to support the sub-board 20 and distribute pressure, preventing the sub-board 20 from tilting, warping, or deforming.

[0052] Step S150: Remove the auxiliary membrane 40 to obtain the pressure sensing module 100.

[0053] For details, please refer to Figure 5 In (b) and (c), after mounting the sub-board 20, the auxiliary film 40 is removed from the flexible circuit board 10, creating a gap between the sub-board 20 and the circuit board unit 111. Figure 5 (As shown in part G), pressure sensing module 100 is obtained.

[0054] The pressure sensing module 100 includes a sub-board 20 and a circuit board unit 111. The sub-board 20 is fixed to the circuit board unit 111 by a conductive adhesive material 30. Because the conductive adhesive material 30 has a certain thickness, after assembly, there is a gap of a preset height (H) between the sub-board 20 and the flexible circuit board 10, allowing the pressure sensing module 100 to obtain a certain capacitance value. During use, the sub-board 20 can deform towards the flexible circuit board 10 under force, causing a change in the height of the gap between the sub-board 20 and the flexible circuit board 10, thereby changing the capacitance value of the pressure sensing module 100. The flexible circuit board 10 determines the pressure detection result based on the change in capacitance value.

[0055] The manufacturing method of the pressure sensing module provided in this application involves setting an auxiliary film 40 on the flexible circuit board 10 before mounting the sub-board 20. This ensures that the auxiliary film 40 is positioned in the gap between the flexible circuit board 10 and the sub-board 20 during the mounting process, guaranteeing a stable gap height. The auxiliary film 40 supports the sub-board 20, providing support and dispersing pressure during mounting, reducing deformation and warping of the sub-board 20, and ensuring equal and constant height values ​​at the same gap position. Therefore, the auxiliary film 40 improves the stability and uniformity of the gap, resulting in a pressure sensing module 100 with good gap consistency and avoiding differences in gap height values ​​among modules of the same model. Thus, the manufacturing method provided in this application solves the problem of difficulty in controlling the gap height value in the pressure sensing module 100.

[0056] This solution uses an auxiliary film 40 to fill the gaps. Compared with existing technologies, the auxiliary film 40 has better processability, allowing for complete board mounting in one go, eliminating the need to individually cover each circuit board unit 111, thus increasing production efficiency. Furthermore, the auxiliary film 40, like the flexible circuit board 10, is flexible. Applying and removing the auxiliary film 40 will not damage the sub-board 20; removal is simple as it can be pulled out directly.

[0057] The thickness of the auxiliary film 40 is adapted to the gap after the pressure sensing module 100 is assembled. Optionally, the thickness of the auxiliary film 40 is equal to the preset height value (H) of the gap, that is, the thickness of the auxiliary film 40 is set according to the height value of the gap required by the design. By setting the auxiliary film 40 of the preset thickness between the flexible circuit board 10 and the sub-board 20 before pressing, the gap position is not easily deformed. It can be understood that the thickness of the auxiliary film 40 can also be slightly less than the preset height of the gap, as long as it can support the sub-board 20.

[0058] like Figure 2 , Figure 4 As shown, the flexible circuit board 10 includes a circuit area 101 and a board edge area 102 surrounding the outside of the circuit area 101, and the circuit area 101 includes a plurality of circuit board units 111; the auxiliary film 40 is simultaneously disposed on the surface of the plurality of circuit board units 111.

[0059] By adopting the above technical solution, an auxiliary film 40 can be set on the surface of multiple circuit board units 111, eliminating the need to attach an auxiliary film 40 separately to each circuit board unit 111, thus improving manufacturing efficiency.

[0060] In the embodiment, the flexible circuit board 10 is in a tiled structure, and one flexible circuit board 10 includes a plurality of circuit board units 111. The tiling is mainly to improve the production and processing efficiency, and one tiling can produce a plurality of circuit board units 111 at the same time, and the rapid mounting and pressing can form a plurality of pressure sensing modules 100 products. It can be understood that each circuit board unit 111 is mounted with the corresponding sub-board 20 to form a pressure sensing module 100. After step S150, the flexible circuit board 10 can be cut to form a single pressure sensing module product; or the tiling structure can be directly shipped to the client, and the client can process according to the subsequent assembly requirements. The shape and arrangement number of the circuit board unit 111 in the figure are only illustrative. In other embodiments, the flexible circuit board 10 is not limited to the tiling structure, and can include only one circuit board unit 111.

[0061] In an embodiment, before the auxiliary film 40 is attached to the surface of the flexible circuit board 10, the manufacturing method further includes: cutting the auxiliary film 40 according to the size of the flexible circuit board 10 to form a plurality of windowing portions in the auxiliary film 40, and the windowing portions are used to expose the pads 11. In this way, the manufacturing method cuts the auxiliary film 40 in advance, so that the auxiliary film 40 is adapted to the size of the flexible circuit board 10, and the windowing portions 41 are made on the auxiliary film 40, which facilitates the subsequent attachment of the auxiliary film 40.

[0062] Optionally, the size of the auxiliary film 40 can cover all the circuit board units 111 on the flexible circuit board 10, that is, the auxiliary film 40 can be attached to the flexible circuit board 10 as a whole. It can be understood that the size of the auxiliary film 40 can also be set to cover part of the circuit board units 111, for example, one auxiliary film 40 covers one row of circuit board units 111. The windowing portion 41 is used to expose the pad 11 to avoid the pad 11. In addition, in the circuit area 101, the connection area between the circuit board units 111 is an auxiliary area. The auxiliary area or the unit of the flexible circuit board 10 is provided with a mark point, that is, an optical recognition point, which is used for alignment when the sub-board 20 is mounted. The windowing portion is also used to expose the mark point.

[0063] In an embodiment, as shown in Figure 3 , Figure 4 One windowing portion 41 of the auxiliary film 40 is arranged in the middle of the auxiliary film 40 and exposes the pads 11 of a plurality of circuit board units 111. For example, the windowing portion 41 is rectangular, and the windowing portion 41 corresponds to two rows of circuit board units 111 and exposes one pad 11 in the corresponding circuit board unit 111.

[0064] By using the above technical solution, the auxiliary film 40 is conveniently cut, and a large number of windowing portions do not need to be arranged, and the manufacturing efficiency is improved.

[0065] In an embodiment, two pads 11 in the circuit board unit 111 are arranged along the first direction (Y direction) at intervals; in the first direction, the size of the auxiliary film 40 is smaller than the size of the circuit area 101, one pad 11 in the circuit board unit 111 is arranged in the windowed portion 41, and the other pad 11 is arranged on the side of the auxiliary film 40 close to the board edge area 102.

[0066] In the first direction, the pad 11 of the circuit board unit 111 can be avoided by the auxiliary film 40, and the windowed portion 41 of the auxiliary film 40 exposes the other pad 11 in the circuit board unit 111. In this way, the number of windowed portions 41 can be reduced by cutting the auxiliary film 40. In the second direction (X direction) perpendicular to the first direction, the size of the auxiliary film 40 is greater than the size of the circuit area 101, so that the end of the auxiliary film 40 can be attached to the board edge area 102.

[0067] In an embodiment, at least one end of the auxiliary film 40 is an attachment portion 42, and the auxiliary film 40 is attached to the board edge area 102 through the attachment portion 42. As shown in Figure 4 Optionally, both ends of the auxiliary film 40 along the length direction are attachment portions, and the size of both ends along the width direction is smaller than the size of the circuit area 101, so that the auxiliary film 40 can be attached to the board edge area 102 through the attachment portion 42, and other regions of the auxiliary film 40 directly cover the flexible circuit board 10 without attachment. In this way, the auxiliary film 40 does not need to be attached to the flexible circuit board 10 as a whole, the attachment area is small, and it is convenient to remove the auxiliary film 40 subsequently.

[0068] This embodiment only provides a cutting and attaching method of the auxiliary film 40. Corresponding to different layout modes, the cutting size and attachment area of the auxiliary film 40 can be flexibly adjusted, as long as the auxiliary film 40 can be supported in the gap between the pressing and soldering and removed smoothly at last, which belongs to the feasible range.

[0069] In an embodiment, the step S150 of removing the auxiliary film 40 includes: cutting the attachment portion 42 of the auxiliary film 40 on the flexible circuit board 10, so that the attachment portion 42 can be separated from the corresponding board edge area 102, and then pulling out the auxiliary film 40 from one side of the flexible circuit board 10.

[0070] In another embodiment, the step S150 of removing the auxiliary film 40 includes: peeling the attachment portion 42 from the board edge area 102, and then pulling out the auxiliary film 40 from one side of the flexible circuit board 10.

[0071] Since the auxiliary film 40 is attached to the board edge area only through the attachment portion, when the auxiliary film 40 is removed, only the attachment portion 42 needs to be cut or separated from the board edge area 102, and then the whole auxiliary film 40 can be pulled out, which is convenient and efficient.

[0072] The conductive adhesive material 30 can be conductive glue, and the step S140 of attaching the sub-plate 20 to the circuit board unit 111 includes: using an automatic reinforcement machine to attach the sub-plate 20 to the circuit board unit 111, and pre-fixing the sub-plate 20 and the flexible circuit board 10, and then using a vacuum pressing machine to press the sub-plate 20 and the circuit board unit 111, so as to ensure the bonding reliability of the flexible circuit board 10 and the sub-plate 20. In the embodiment, the vacuum fast pressing machine is used for pressing, and the sub-plate 20 is pressed with the upper surface facing upward, and a release film and a pressing buffer material are further arranged outside the flexible circuit board 10 and the sub-plate 20. Specifically, the release film is arranged on the side of the sub-plate 20 away from the flexible circuit board 10 and on the side of the flexible circuit board 10 away from the sub-plate 20, and the pressing buffer material such as glass fiber cloth is placed below the flexible circuit board 10 on which the release film is arranged. The first piece after pressing needs to be checked for the peel strength of the conductive glue, the offset condition and the gap height value after pressing, so as to timely adjust the process parameters of the subsequent products. Alternatively, the conductive glue is a thermosetting conductive glue, and the conductive glue is baked using an oven after pressing, so as to completely solidify the conductive glue.

[0073] It should be noted that the size of the conductive glue should be reasonably set according to the flowability of the conductive glue during pressing, so that the conductive glue covers and bonds the pads 11 after pressing, and does not overflow the edges of the flexible circuit board 10 and the sub-plate 20.

[0074] The conductive adhesive material 30 can also be solder paste, and the step S140 of attaching the sub-plate 20 to the flexible circuit board 10 includes: using an automatic chip mounter to attach the sub-plate 20 to the circuit board unit 111, and then performing reflow soldering.

[0075] Specifically, the solder paste is printed on the pads 11 of the flexible circuit board 10 in a steel mesh printing manner. It should be noted that the amount of the solder paste should be controlled, so that the melted solder paste meets the welding requirements, and does not affect the gap height value due to being too much. In actual production, the production first board can be set according to the size of the gap height value, and the amount of the solder paste printed can be adjusted according to the attachment condition of the first board. The automatic chip mounter is used for mounting, and the sub-plate 20 is accurately attached to the preset position and then reflow soldering is performed. The flexible circuit board 10 and the sub-plate 20 after mounting are sent into a reflow soldering furnace, so that the sub-plate 20 and the flexible circuit board 10 are firmly bonded together. During reflow soldering, the solder paste is melted, and a pulling force is generated between the pads 11 and the sub-plate 20 from the melted state of the solder paste to the solidified state, but the auxiliary film 40 fills the gap position and supports the sub-plate 20, so that the solder paste at both ends of the gap position after solidification remains relatively constant.

[0076] Please refer to Figure 1 , Figure 6In another embodiment, in step S120, the auxiliary film 40 is provided in multiple pieces, and the multiple pieces of the auxiliary film 40 are arranged at intervals, each piece of the auxiliary film 40 corresponding to a row of the circuit board units 111 and extending between two rows of the pads 11, and the width of the auxiliary film 40 is less than or equal to the distance between the two pads 11. At this time, it is not necessary to provide the auxiliary film 40 with a window portion exposing the pads 11.

[0077] In the embodiment, only the multiple pieces of the auxiliary film 40 need to be cut and provided with the window portion exposing the mark, and each piece of the auxiliary film 40 can still cover multiple circuit board units 111 at the same time. It can be understood that the shape of the auxiliary film 40 is not limited in the present application.

[0078] The second aspect of the present application provides a pressure sensing module 100, which is manufactured by the manufacturing method of the pressure sensing module 100 of any one of the embodiments of the first aspect.

[0079] The pressure sensing module 100 includes a flexible circuit board 10 and a sub-board 20 for pressure sensing, the flexible circuit board 10 is provided with pads 11, and the sub-board 20 is fixed to the pads 11 by a conductive adhesive material; a gap with a preset height is formed between the sub-board 20 and the flexible circuit board 10.

[0080] When the sub-board 20 is subjected to an external applied pressure, the height of the gap changes, and then the capacitance value of the pressure sensing module 100 changes, and the flexible circuit board 10 can determine the pressure detection result based on the change of the capacitance value. The pressure sensing module 100 can be used in TWS earphones or other electronic devices that need to detect pressure.

[0081] In the manufacturing process of the pressure sensing module 100 provided by the present application, the auxiliary film 40 is used to support the sub-board 20 and fill the gap, which improves the stability and uniformity of the gap. Therefore, the capacitance consistency of the above-mentioned pressure sensing module 100 is good, and the above-mentioned pressure sensing module 100 is not easy to deform during manufacturing, and the yield is good.

[0082] The pressure sensing module 100 and the manufacturing method thereof provided by the present application can ensure the stability and consistency of the gap between the sub-board 20 and the flexible circuit board 10 in the pressure sensing module 100, and improve the product yield and product quality.

[0083] The above embodiments are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacements for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application.

Claims

1. A method for manufacturing a pressure sensing module, characterized in that, include: A flexible circuit board and a sub-board are provided. The flexible circuit board has a panel structure. The flexible circuit board includes a circuit area and a board edge area surrounding the outside of the circuit area. The circuit area is provided with multiple circuit board units and the circuit board units are provided with solder pads. The auxiliary film is cut according to the size of the flexible circuit board to form a plurality of openings in the auxiliary film, the openings being used to expose the pads; An auxiliary film is attached to the surface of the flexible circuit board. The auxiliary film is flexible and is simultaneously disposed on the surface of multiple circuit board units. The auxiliary film covers at least a portion of the circuit board units and exposes the pads. At least one end of the auxiliary film is an adhesive portion, and the auxiliary film is adhered to the edge area of ​​the board through the adhesive portion. The other areas of the auxiliary film directly cover the flexible circuit board. A conductive adhesive material is applied to the pad or to the corresponding location on the sub-board. The sub-board is mounted on the circuit board unit, wherein the auxiliary film is located between the sub-board and the circuit board unit, and the conductive adhesive material bonds the sub-board and the pads; Remove the auxiliary film and cut the flexible circuit board to obtain a plurality of individual pressure sensing modules. The pressure sensing module includes the circuit board unit and the sub-board, wherein a gap is formed between the sub-board and the circuit board unit. The thickness of the auxiliary membrane is equal to the preset height of the gap.

2. The method for manufacturing the pressure sensing module as described in claim 1, characterized in that, An opening portion of the auxiliary film is located in the middle of the auxiliary film and simultaneously exposes the pads of multiple circuit board units.

3. The method for manufacturing the pressure sensing module as described in claim 1, characterized in that, The auxiliary film consists of multiple auxiliary films spaced apart. Each auxiliary film corresponds to a row of circuit board units and extends between two rows of pads. The width of the auxiliary film is less than or equal to the distance between two pads.

4. The method for manufacturing the pressure sensing module as described in claim 1, characterized in that, The removal of the auxiliary membrane includes: Cut the adhesive portion of the auxiliary film on the flexible circuit board, and then pull the auxiliary film out from one side of the flexible circuit board; or, Peel the adhesive part off the edge of the board, and then pull out the auxiliary film from one side of the flexible circuit board.

5. The method for manufacturing the pressure sensing module as described in any one of claims 1-4, characterized in that, The conductive adhesive material is conductive glue. The process of attaching the sub-board to the circuit board unit includes: using an automatic reinforcing machine to attach the sub-board to the circuit board unit, and then using a vacuum press to press the sub-board and the circuit board unit together; or... The conductive adhesive material is solder paste, and the step of mounting the sub-board onto the flexible circuit board includes: using an automatic pick-and-place machine to mount the sub-board onto the circuit board unit, and then performing reflow soldering.

6. A pressure sensing module, characterized in that, It is manufactured using the method for manufacturing a pressure sensing module as described in any one of claims 1-5.

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