Circuit board, screen assembly, and electronic device

Abstract

The application discloses a circuit board, a screen assembly and an electronic device. The circuit board comprises a circuit substrate, the circuit substrate is provided with a first electrode plate and a second electrode plate, a gap is formed between the first electrode plate and the second electrode plate, and a potential difference is formed between the first electrode plate and the second electrode plate; and a capacitive sensing part is arranged on the circuit substrate and connected between the first electrode plate and the second electrode plate. When solder migrates to the capacitive sensing part, the capacitance of the capacitive sensing part changes, and the capacitance of the capacitive sensing part is used for identifying the working state of the circuit substrate.

Description

Technical Field

[0001] This application belongs to the technical field of electronic devices, specifically relating to a circuit board, a screen assembly, and an electronic device. Background Technology

[0002] Electronic devices include screen assemblies, which in turn include circuit boards. Circuit boards are connected via a soldering process. However, this connection method has drawbacks. Specifically, insufficient soldering time or temperature can lead to incomplete flux reaction at the board's connection points. Incompletely reacted flux contains activators, organic acids, and other substances that exhibit conductivity. As the electronic device operates over time, copper and tin migration can occur between traces at different potentials on the circuit board, ultimately causing short circuits.

[0003] In related technologies, electronic devices do not have the function of detecting whether copper or tin migration occurs on the circuit board during use. They are only disassembled for repair when a short circuit occurs between the traces on the circuit board, causing abnormal screen display. This will greatly increase the repair cost of electronic devices and shorten their service life. Summary of the Invention

[0004] This application aims to provide a circuit board, screen assembly, and electronic device, which solves one of the problems in the related technology: the electronic device does not have the function of detecting whether copper or tin migration occurs during the use of the circuit board, resulting in high maintenance costs and short service life of the electronic device.

[0005] To solve the above-mentioned technical problems, this application is implemented as follows:

[0006] In a first aspect, embodiments of this application propose a circuit board, comprising: a circuit board having a first electrode plate and a second electrode plate, a gap between the first electrode plate and the second electrode plate, and a potential difference between the first electrode plate and the second electrode plate; and a capacitance sensing unit disposed on the circuit board and connected between the first electrode plate and the second electrode plate; wherein, when solder migrates to the capacitance sensing unit, the capacitance value of the capacitance sensing unit changes, and the capacitance value of the capacitance sensing unit is used to indicate the working state of the circuit board.

[0007] Secondly, embodiments of this application provide a screen assembly, including: a screen body; and the circuit board mentioned in the first aspect, the circuit board being located on one side of the screen body.

[0008] Thirdly, embodiments of this application provide an electronic device, including: a housing; and the screen assembly as described in the second aspect, wherein the screen assembly is disposed on the housing.

[0009] In embodiments of this application, the circuit board includes a circuit board and a capacitive sensing unit.

[0010] The circuit board has a first electrode and a second electrode, with a gap between them and a potential difference between them. External components are connected to the first and second electrodes by soldering.

[0011] The capacitive sensing element is disposed on the circuit board and connected between the first and second plates. The capacitive sensing element is electrically connected to the first plate and also electrically connected to the second plate. That is, capacitive sensing elements are added in different potential ranges of the circuit board.

[0012] The circuit board is used in electronic devices. It is electrically connected to the controller of the electronic device, and the controller is also electrically connected to the alarm of the electronic device. As the electronic device operates for an extended period, if solder (e.g., undried flux or other conductive solvents) from the first and / or second plates migrates to the capacitance sensing unit, the impedance change will cause a change in the capacitance value of the capacitance sensing unit. When the capacitance value of the capacitance sensing unit is greater than or equal to a preset value, the controller activates the alarm of the electronic device to indicate that the current operating state of the circuit board is abnormal. When the capacitance value of the capacitance sensing unit is less than the preset value, it indicates that the current operating state of the circuit board is normal. In other words, the capacitance value of the capacitance sensing unit is used to identify the operating state of the circuit board.

[0013] Therefore, by rationally designing the circuit board structure and using the capacitance value of the capacitor sensing unit to indicate the working status of the circuit board, electronic devices can acquire the function of detecting the working status of the circuit board. This allows for timely and effective detection of abnormal circuit board conditions, providing structural support for timely and effective circuit board repair. It also prevents short circuits between circuit board traces caused by excessive copper and tin migration areas, effectively reducing the repair and maintenance costs of electronic devices, extending their service life, and improving their performance and market competitiveness.

[0014] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0015] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0016] Figure 1 This is a schematic diagram of the circuit board structure according to the first embodiment of this application;

[0017] Figure 2This is a partial structural schematic diagram of the circuit board according to the first embodiment of this application;

[0018] Figure 3 This is a partial structural diagram of the circuit board according to the second embodiment of this application.

[0019] Figure 4 This is an exploded view of a partial structure of an electronic device according to an embodiment of this application.

[0020] Figure label:

[0021] Figures 1 to 4 The correspondence between the reference numerals and component names in the attached drawings is as follows:

[0022] 10 Circuit board, 100 Circuit board substrate, 110 First electrode plate, 112 First end face, 114 Second end face, 120 Second electrode plate, 122 Third end face, 124 Fourth end face, 140 Conductive layer, 142 First groove, 144 Second groove, 150 First adhesive layer, 160 Second adhesive layer, 172 First polyimide layer, 174 Second polyimide layer, 180 Copper plating layer, 190 Third adhesive layer, 200 Capacitive sensing part, 210 Fifth end face, 220 Sixth end face, 300 Conductive structure, 310 Wire group, 310a First wire group, 310b Second wire group, 312 Wire, 40 Electronic device, 400 Controller, 500 Alarm, 600 Housing. Detailed Implementation

[0023] The embodiments of this application will now be described in detail. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0024] The terms "first" and "second" in the specification and claims of this application may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise stated, "multiple" means two or more. Furthermore, "and / or" in the specification and claims indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0025] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0026] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0027] The following is in conjunction with the appendix Figures 1 to 4 This application describes the circuit board 10, screen assembly, and electronic device 40 provided in embodiments of this application.

[0028] like Figure 1 and Figure 2 As shown, a circuit board 10 according to some embodiments of this application includes: a circuit board 100, the circuit board 100 having a first electrode plate 110 and a second electrode plate 120, a gap between the first electrode plate 110 and the second electrode plate 120, and a potential difference between the first electrode plate 110 and the second electrode plate 120; a capacitance sensing unit 200, disposed on the circuit board 100, the capacitance sensing unit 200 being connected between the first electrode plate 110 and the second electrode plate 120; wherein, when solder migrates to the capacitance sensing unit 200, the capacitance value of the capacitance sensing unit 200 changes, and the capacitance value of the capacitance sensing unit 200 is used to indicate the working state of the circuit board 100.

[0029] In the embodiments of this application, the circuit board 10 includes a circuit board 100 and a capacitive sensing part 200.

[0030] The circuit board 100 has a first electrode 110 and a second electrode 120, with a gap between the first electrode 110 and the second electrode 120, and a potential difference between the first electrode 110 and the second electrode 120. External components are connected to the first electrode 110 and the second electrode 120 by soldering.

[0031] The capacitive sensing unit 200 is disposed on the circuit board 100 and connected between the first electrode 110 and the second electrode 120. The capacitive sensing unit 200 is electrically connected to the first electrode 110 and also electrically connected to the second electrode 120. That is, the capacitive sensing unit 200 is added in different potential ranges of the circuit board 100.

[0032] Circuit board 10 is used in electronic device 40. Circuit board 10 is electrically connected to controller 400 of electronic device 40, and controller 400 is also electrically connected to alarm 500 of electronic device 40. As the operating time of electronic device 40 increases, if solder (e.g., conductive solvent such as undried flux) at the first electrode 110 and / or the second electrode 120 migrates to the capacitance sensing unit 200, the capacitance value of capacitance sensing unit 200 will change due to impedance change. When the capacitance value of capacitance sensing unit 200 is greater than or equal to a preset value, controller 400 controls alarm 500 of electronic device 40 to sound an alarm to indicate that the current operating state of circuit board 100 is abnormal. When the capacitance value of capacitance sensing unit 200 is less than the preset value, it indicates that the current operating state of circuit board 100 is normal. That is, the capacitance value of capacitance sensing unit 200 is used to identify the operating state of circuit board 10.

[0033] Therefore, by rationally designing the structure of the circuit board 10 and using the capacitance value of the capacitance sensing unit 200 to indicate the working state of the circuit board 100, the electronic device 40 has the function of detecting the working state of the circuit board 10. This allows for timely and effective detection of whether the circuit board 10 is in an abnormal state, providing structural support for timely and effective repair of the circuit board 10. It also prevents short circuits between traces on the circuit board 100 caused by excessive copper or tin migration areas, effectively reducing the repair and maintenance costs of the electronic device 40, extending its service life, and improving its performance and market competitiveness.

[0034] Optionally, one of the first electrode plate 110 and the second electrode plate 120 is a positive electrode plate, and the other of the first electrode plate 110 and the second electrode plate 120 is a negative electrode plate.

[0035] Optionally, one of the first electrode plate 110 and the second electrode plate 120 is a positive electrode plate, and the other of the first electrode plate 110 and the second electrode plate 120 is ground.

[0036] Optionally, one of the first electrode plate 110 and the second electrode plate 120 is a negative electrode plate, and the other of the first electrode plate 110 and the second electrode plate 120 is ground.

[0037] In some embodiments, when the capacitance value of the capacitive sensing unit is greater than or equal to a preset value, the operating state of the circuit board is identified as an abnormal operating state; when the capacitance value of the capacitive sensing unit is less than the preset value, the operating state of the circuit board is identified as a normal operating state.

[0038] In this embodiment, the specific operating state of the circuit board is identified based on the relationship between the capacitance value of the capacitance sensing unit and a preset value.

[0039] It is understandable that C = ε × S / (4 × π × k × d), where C is the capacitance, ε is the dielectric constant, S is the area of ​​the capacitor plates facing each other, d is the distance between the capacitor plates, and k is the electrostatic constant. When the solder migrates to the capacitor induction section 200, it will cause a change in the dielectric constant of the first plate 110 (e.g., the positive plate) and the second plate 120 (e.g., the negative plate).

[0040] The preset values ​​can be determined based on ε, S, k, and d.

[0041] For example, the dielectric constant of air is 1, and the dielectric constant of water is 80. Solder residue (such as solvent) will increase the dielectric constant; the more solder residue, the greater the dielectric constant. Combining this with the formula C = ε × S / (4 × π × k × d), we can conclude that more solvent residue will result in a larger capacitance value. That is, the operating state of the circuit board 100 can be indicated by the capacitance value of the capacitance sensing unit 200. The more solvent residue, the larger the capacitance value of the capacitance sensing unit 200. When the capacitance value of the capacitance sensing unit 200 is greater than or equal to a preset value, the operating state of the circuit board 100 is indicated as an abnormal operating state; when the capacitance value of the capacitance sensing unit 200 is less than the preset value, the operating state of the circuit board 100 is indicated as a normal operating state. When the operating state of the circuit board 100 is indicated as an abnormal operating state, a corresponding reminder or alarm will be issued to attract the user's attention, allowing the user to promptly understand the operating status of the circuit board 10.

[0042] Based on this principle, a correspondence table between capacitance and impedance values ​​is created using statistical software, and corresponding warning prompts are set. Further refinement can be achieved by defining a first limit and a second limit, both determined by ε, S, k, and d. The first limit corresponds to C1, the second limit to C2, and the preset value to C0. For example, an impedance value greater than 500MΩ is normal (corresponding to capacitance value C0), an impedance value less than 500MΩ may pose a risk (corresponding to capacitance value C1), and an impedance value less than 100MΩ is considered high-risk (corresponding to capacitance value C2). From the above capacitance formula, C0 < C1 < C2 can be calculated. When the capacitance value is less than C0, the current operating state of the circuit board 100 is normal. When the capacitance value is greater than or equal to C0 and less than C1, a warning is issued. When the capacitance value is greater than or equal to C1 and less than C2, an alarm is displayed.

[0043] In some embodiments, such as Figure 1 As shown, the circuit board 10 also includes a conductive structure 300, which connects the circuit board 100 and the capacitive sensing unit 200, and is used to transmit signals from the capacitive sensing unit 200.

[0044] In this embodiment, the structure of the circuit board 10 is further defined.

[0045] The circuit board 10 also includes a conductive structure 300.

[0046] The conductive structure 300 is connected to the circuit board 100 and also to the capacitive sensing unit 200. That is, the capacitive sensing unit 200 is electrically connected to the circuit board 100 through the conductive structure 300.

[0047] The conduction structure 300 is used to electrically connect with external devices (such as the controller 400 of the electronic device 40) to realize the transmission of signals from the capacitance sensing unit 200. It provides structural support for the controller 400 of the electronic device 40 to control the alarm 500 to work according to the capacitance value of the capacitance sensing unit 200, and provides structural support for the electronic device 40 to have the function of detecting the working status of the circuit board 10.

[0048] In some embodiments, such as Figure 1 and Figure 2 As shown, the conductive structure 300 is located between the first electrode plate 110 and the second electrode plate 120; the conductive structure 300 includes a wire group 310, which includes two wires 312 along the direction from the first electrode plate 110 to the second electrode plate 120, with a gap between the two wires 312, the wires 312 connecting the circuit board 100 and the capacitive sensing part 200, and one end of the wires 312 exposing the capacitive sensing part 200.

[0049] In this embodiment, the composition of the conducting structure 300 is further defined.

[0050] The conductive structure 300 includes a conductor group 310, which includes two conductors 312. There is a gap between the two conductors 312 along the direction from the first electrode plate 110 to the second electrode plate 120.

[0051] Each wire 312 connects the circuit board 100 and the capacitive sensing unit 200, and one end of the wire 312 exposes the capacitive sensing unit 200. When solder (e.g., conductive solvent such as undried flux) migrates to the two wires 312 of the wire assembly 310, the solder will short-circuit the two wires 312 of the wire assembly 310. In this way, on the one hand, the short circuit of the two wires 312 can generate heat, which can dry the conductive solvent on the surface of the capacitive sensing part 200, thus achieving the purpose of drying the conductive solvent. On the other hand, for the dendrites formed at the capacitive sensing part 200 due to incomplete drying, since the wire group 310 is located between the first electrode plate 110 and the second electrode plate 120, the distance between the two wires 312 of the wire group 310 is smaller than the distance between the first electrode plate 110 and the second electrode plate 120. Therefore, the solder (such as undried flux and other conductive solvents) will preferentially react at the wire group 310. In this way, the purpose of preventing dendrite growth on the first electrode plate 110 and the second electrode plate 120 is achieved, further reducing the probability of short circuit in the circuit board 100.

[0052] It is understandable that if there is no capacitive sensing part between the first plate and the second plate, the part of the circuit board located between the first plate and the second plate will form dendrites due to the presence of conductive solvent and the potential difference between the first plate and the second plate. When the dendrites connect the first plate and the second plate, it will cause the circuit board to short circuit, and the electronic device will have a problem with the display exploding.

[0053] In other words, this application has reasonably set up a cooperative structure of conductive structure 300, circuit board 100 and capacitive sensing part 200, which can not only dry the conductive solvent, but also prevent dendrite growth in the first electrode plate 110 and the second electrode plate 120.

[0054] Specifically, one end of the wire 312 exposes the capacitive sensing part 200. That is, one end of the wire 312 is not blocked by the capacitive sensing part 200, and one end of the wire 312 is used for electrical connection with external devices. Optionally, the capacitive sensing part 200 is provided with an opening, and one end of the wire 312 exposes the capacitive sensing part 200 through the opening.

[0055] In some embodiments, such as Figure 1 As shown, the circuit board 10 includes multiple sets of wire groups 310, which include a first set of wire groups 310a and a second set of wire groups 310b. The first set of wire groups 310a is closer to the first electrode plate 110 than the second electrode plate 120, and the second set of wire groups 310b is closer to the second electrode plate 120 than the first electrode plate 110.

[0056] In this embodiment, the composition of the conducting structure 300 is further defined.

[0057] The circuit board 10 includes multiple sets of wire groups 310. The multiple sets of wire groups 310 are divided such that the multiple sets of wire groups 310 include a first set of wire groups 310a and a second set of wire groups 310b.

[0058] The first conductor group 310a and the second conductor group 310b are positioned differently. Specifically, the first conductor group 310a is closer to the first electrode plate 110 than the second electrode plate 120; that is, the distance from the first conductor group 310a to the first electrode plate 110 is less than the distance from the first conductor group 310a to the second electrode plate 120. Similarly, the second conductor group 310b is closer to the second electrode plate 120 than the first electrode plate 110; that is, the distance from the second conductor group 310b to the second electrode plate 120 is less than the distance from the second conductor group 310b to the first electrode plate 110. In other words, the first conductor group 310a is located at the first electrode plate 110, and the second conductor group 310b is located at the second electrode plate 120.

[0059] The first lead wire assembly 310a is used to dry the conductive solvent that migrates to the capacitive sensing part 200 via the first electrode plate 110. The first lead wire assembly 310a is also used to prevent dendrite growth in the first electrode plate 110 and the second electrode plate 120.

[0060] The second lead wire assembly 310b is used to dry the conductive solvent that migrates to the capacitive sensing part 200 via the second electrode plate 120. The second lead wire assembly 310b is also used to prevent dendrite growth in the first electrode plate 110 and the second electrode plate 120.

[0061] The first wire group 310a and the second wire group 310b work together to simultaneously dry the conductive solvent that migrates to the capacitive sensing part 200 via the first electrode plate 110 and the second electrode plate 120, thereby effectively improving the effect of preventing dendrite growth in the first electrode plate 110 and the second electrode plate 120.

[0062] Optionally, the number of the first conductor group 310a is at least one group.

[0063] Optionally, the number of the second conductor group 310b is at least one group.

[0064] In some embodiments, the first electrode plate 110, the second electrode plate 120, and the capacitive sensing part 200 are located on the same side of the circuit board 100.

[0065] In this embodiment, the positions of the first electrode plate 110, the second electrode plate 120, and the capacitive sensing unit 200 are further defined.

[0066] The first electrode plate 110, the second electrode plate 120, and the capacitive sensing part 200 are located on the same side of the circuit board 100.

[0067] This arrangement ensures the effective cooperation between the first electrode plate 110, the second electrode plate 120, and the capacitive sensing unit 200, while reducing the difficulty of processing the capacitive sensing unit 200, which is beneficial to reducing the size of the capacitive sensing unit 200 and improving the processing efficiency of the capacitive sensing unit 200.

[0068] In some embodiments, such as Figure 3 As shown, along the thickness direction of the circuit board 100, the heights of the first electrode plate 110 and the second electrode plate 120 are both less than or equal to the height of the capacitive sensing part 200.

[0069] In this embodiment, the cooperative structure of the first electrode plate 110, the second electrode plate 120, and the capacitive sensing unit 200 is further defined.

[0070] Along the thickness direction of the circuit board 100, the height of the first electrode plate 110 is less than or equal to the height of the capacitive sensing part 200.

[0071] Along the thickness direction of the circuit board 100, the height of the second electrode plate 120 is less than or equal to the height of the capacitive sensing part 200.

[0072] When the height of the first electrode plate 110 is less than the height of the capacitive sensing part 200 along the thickness direction of the circuit board 100, there is a height difference between the first electrode plate 110 and the capacitive sensing part 200. The position height of the first electrode plate 110 is lower than the position height of the capacitive sensing part 200. The first electrode plate 110 and the capacitive sensing part 200 will form an L-shaped structure, which can accommodate the solder used to connect external devices and prevent the solder from migrating to the capacitive sensing part 200. This can reduce the probability of solder migrating to the capacitive sensing part 200 via the first electrode plate 110.

[0073] When the height of the second electrode plate 120 is less than the height of the capacitive sensing part 200 along the thickness direction of the circuit board 100, there is a height difference between the second electrode plate 120 and the capacitive sensing part 200. The position height of the second electrode plate 120 is lower than the position height of the capacitive sensing part 200. The second electrode plate 120 and the capacitive sensing part 200 will form an L-shaped structure, which can accommodate the solder used to connect external devices and prevent the solder from migrating to the capacitive sensing part 200. This can reduce the probability of solder migrating to the capacitive sensing part 200 via the second electrode plate 120.

[0074] Specifically, such as Figure 3As shown, along the thickness direction of the circuit board 100, the first electrode 110 has a first end face 112 and a second end face 114, and the capacitive sensing unit 200 has a fifth end face 210 and a sixth end face 220. Both the first end face 112 and the fifth end face 210 are connected to the circuit board 100. The second end face 114 is closer to the side of the circuit board 100 away from the capacitive sensing unit 200 than the sixth end face 220. That is, along the thickness direction of the circuit board 100, the position height of the sixth end face 220 is higher than the position height of the second end face 114, and there is a height difference between the second end face 114 and the sixth end face 220. This allows the first electrode 110 to accommodate solder for connecting external devices, preventing solder from migrating to the capacitive sensing unit 200 and reducing the probability of solder migrating to the capacitive sensing unit 200 via the first electrode 110.

[0075] Specifically, such as Figure 3 As shown, along the thickness direction of the circuit board 100, the second electrode 120 has a third end face 122 and a fourth end face 124, and the capacitive sensing unit 200 has a fifth end face 210 and a sixth end face 220. Both the third end face 122 and the fifth end face 210 are connected to the circuit board 100. The fourth end face 124 is closer to the side of the circuit board 100 away from the capacitive sensing unit 200 than the sixth end face 220. That is, along the thickness direction of the circuit board 100, the position height of the sixth end face 220 is higher than the position height of the fourth end face 124, and there is a height difference between the fourth end face 124 and the sixth end face 220. This allows the second electrode 120 to accommodate solder for connecting external devices, preventing solder from migrating to the capacitive sensing unit 200 and reducing the probability of solder migrating to the capacitive sensing unit 200 via the second electrode 120.

[0076] This setting helps improve the yield rate of circuit board 10 and reduces the probability of circuit board 10 failure.

[0077] In some embodiments, such as Figure 2 As shown, the circuit board 100 includes: a conductive layer 140, with a first groove 142 and a second groove 144 on the same side of the conductive layer 140; a first electrode plate 110 disposed in the first groove 142; a second electrode plate 120 disposed in the second groove 144; a portion of the capacitive sensing part 200 covering the opening of the first groove 142; and another portion of the capacitive sensing part 200 covering the opening of the second groove 144; a first adhesive layer 150 disposed in the first groove 142, which is used to connect the conductive layer 140, the first electrode plate 110, and the capacitive sensing part 200; and a second adhesive layer 160 disposed in the second groove 144, which is used to connect the conductive layer 140, the second electrode plate 120, and the capacitive sensing part 200.

[0078] In this embodiment, the structure of the circuit board 100 is refined.

[0079] The circuit board 100 includes a conductive layer 140, a first adhesive layer 150, and a second adhesive layer 160.

[0080] A first groove 142 and a second groove 144 are provided on the same side of the conductive layer 140.

[0081] The first electrode plate 110 is disposed in the first groove 142, and the second electrode plate 120 is disposed in the second groove 144.

[0082] A portion of the capacitive sensing unit 200 covers the opening of the first groove 142, and another portion of the capacitive sensing unit 200 covers the opening of the second groove 144.

[0083] The first adhesive layer 150 located in the first groove 142 connects the conductive layer 140, the first electrode plate 110 and the capacitive sensing part 200.

[0084] The second adhesive layer 160 located in the second groove 144 connects the conductive layer 140, the second electrode plate 120 and the capacitive sensing part 200.

[0085] Optionally, such as Figure 2 As shown, the circuit board 100 also includes a first polyimide layer 172, a copper plating layer 180, a third adhesive layer 190, and a second polyimide layer 174.

[0086] A screen assembly according to some embodiments of this application includes: a screen body; and a circuit board 10 as described in any of the above embodiments, the circuit board 10 being located on one side of the screen body.

[0087] The screen assembly provided in this application includes the circuit board 10 of any of the above embodiments, and therefore has all the beneficial effects of the circuit board 10, which will not be described in detail here.

[0088] like Figure 4 As shown, an electronic device 40 according to some embodiments of the present application includes: a housing 600; and a screen assembly as described in the above embodiments, the screen assembly being disposed in the housing 600.

[0089] The electronic device 40 provided in this application includes the screen component of any of the above embodiments, and therefore has all the beneficial effects of the screen component, which will not be described in detail here.

[0090] Optionally, the electronic device 40 may be a mobile terminal such as a mobile phone, a wearable device, a tablet computer, a laptop computer, a mobile computer, an augmented reality device (also known as an AR (Augmented Reality) device), a virtual reality device (also known as a VR (Virtual Reality) device), and a handheld game console, etc.

[0091] In some embodiments, such as Figure 4 As shown, the electronic device 40 also includes: a controller 400; an alarm 500, both the alarm 500 and the circuit board 10 are electrically connected to the controller 400, and the controller 400 is used to control the alarm 500 to work according to the capacitance value of the capacitance sensing unit 200.

[0092] In this embodiment, the structure of the electronic device 40 is further defined.

[0093] The electronic device 40 also includes a controller 400 and an alarm 500. The controller 400 is electrically connected to the circuit board 10, and the controller 400 is also electrically connected to the alarm 500.

[0094] If solder (e.g., undried flux or other conductive solvent) at the first electrode plate 110 and / or the second electrode plate 120 moves to the capacitance sensing unit 200, the capacitance value of the capacitance sensing unit 200 will change due to the impedance change. When the capacitance value of the capacitance sensing unit 200 is greater than or equal to a preset value, the controller 400 controls the alarm 500 of the electronic device 40 to issue an alarm to indicate that the current operating state of the circuit board 100 is abnormal.

[0095] Optionally, the circuit board 100 includes a flexible circuit board or a printed circuit board.

[0096] The following example uses circuit board 100 as a flexible circuit board.

[0097] This application adds a capacitance sensing unit 200 to different potential ranges of a flexible circuit board. The capacitance sensing unit 200 is connected to the controller 400 of an electronic device 40 via a conductive structure 300. When solder (e.g., undried flux or other conductive solvent) appears on the capacitance sensing unit 200, the capacitance value of the capacitance sensing unit 200 changes due to impedance changes. Therefore, by setting the capacitance sensing unit 200, the working state of the flexible circuit board can be determined. Simultaneously, at least one set of wire groups 310 is provided in the capacitance sensing unit 200. Each set of wire groups 310 includes two wires 312, each wire 312 connecting the flexible circuit board and the capacitance sensing unit 200, with one end of the wire 312 exposed above the capacitance sensing unit 200. The distance between the two wires 312 in the set of wires 310 is less than the distance between the first electrode 110 and the second electrode 120. When the capacitance value of the capacitance sensing unit 200 is greater than or equal to a preset value, the controller 400 controls the alarm 500 to issue an alarm for early warning. Simultaneously, when the conductive solvent of the solder migrates to the two wires 312 of the wire assembly 310, the conductive solvent will short-circuit the two wires 312. The effect of the short-circuit of the two wires 312 includes the following two aspects: First, the short-circuit of the two wires 312 can generate heat, which can dry the conductive solvent on the surface of the capacitive sensing part 200, achieving the purpose of drying the conductive solvent. Second, for dendrites formed at the capacitive sensing part 200 due to incomplete drying, since the wire assembly 310 is located between the first electrode 110 and the second electrode 120, and the distance between the two wires 312 of the wire assembly 310 is smaller than the distance between the first electrode 110 and the second electrode 120, the solder (such as undried flux and other conductive solvents) will preferentially react at the wire assembly 310. In this way, the purpose of preventing dendrite growth at the first electrode 110 and the second electrode 120 is achieved, further reducing the probability of short circuit in the circuit board 100.

[0098] like Figure 1 As shown, the circuit board 10 includes a circuit board 100, a capacitor sensing part 200 and a conduction structure 300. The circuit board 100 is provided with a first electrode plate 110 and a second electrode plate 120.

[0099] like Figure 2 As shown, the circuit board 10 includes a conductive layer 140, a first electrode plate 110, a conductive structure 300, a first adhesive layer 150, a second adhesive layer 160, a capacitive sensing part 200, a second electrode plate 120, a first polyimide layer 172, a copper plating layer 180, a third adhesive layer 190, and a second polyimide layer 174.

[0100] If there is a conductive solvent between the first electrode plate 110 and the second electrode plate 120, when the circuit board 10 is energized, the capacitance value of the capacitance sensing unit 200 changes due to the presence of the conductive solvent, and the change in capacitance value is transmitted to the controller 400 through the conduction structure 300.

[0101] C = ε × S / (4 × π × k × d), where C is the capacitance, ε is the dielectric constant, S is the area of ​​the capacitor plates facing each other, d is the distance between the capacitor plates, and k is the electrostatic constant. When the solder migrates to the capacitor induction section 200, it causes a change in the dielectric constant of the first plate 110 (e.g., the positive plate) and the second plate 120 (e.g., the negative plate).

[0102] For example, the dielectric constant of air is 1, and the dielectric constant of water is 80. Solder residue (such as solvent) will increase the dielectric constant; the more solder residue, the greater the dielectric constant. Combining this with the formula C=ε×S / (4×π×k×d), we can conclude that the more solvent residue, the greater the capacitance value. That is, the operating state of the circuit board 100 can be determined by the capacitance value of the capacitance sensing unit 200.

[0103] Based on this principle, a correspondence table between capacitance and impedance values ​​is created using statistical software, and corresponding warning prompts are set. For example, an impedance value greater than 500MΩ is normal (corresponding to a capacitance value of C0), an impedance value less than 500MΩ may pose a risk (corresponding to a capacitance value of C1), and an impedance value less than 100MΩ is considered high-risk (corresponding to a capacitance value of C2). From the above capacitance formula, C0 < C1 < C2 can be calculated. When the capacitance value is less than C0, the current operating state of the circuit board 100 is normal. When the capacitance value is greater than or equal to C0 and less than C1, a warning is issued. When the capacitance value is greater than or equal to C1 and less than C2, an alarm is displayed.

[0104] Meanwhile, by setting the conductive structure 300, the conductive solvent will short-circuit the two wires 312 of the wire assembly 310. The heat generated by the short circuit will dry the residual conductive solvent. The distance between the two wires 312 of the wire assembly 310 is smaller than the distance between the first electrode 110 and the second electrode 120 (e.g., the distance between the first electrode 110 and the second electrode 120 is 10 mm, and the distance between the two wires 312 is 0.2 mm). In this way, as long as there is a small area of ​​residual conductive solvent, it will cause the two wires 312 to short-circuit. Dendrites will preferentially grow between the wire assemblies 310 and continuously react and consume, thereby achieving the purpose of preventing dendrite growth in the first electrode 110 and the second electrode 120.

[0105] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0106] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. A circuit board, characterized in that, include: A circuit board having a first electrode plate and a second electrode plate, a gap between the first electrode plate and the second electrode plate, and a potential difference between the first electrode plate and the second electrode plate; A capacitive sensing unit is disposed on the circuit board, and the capacitive sensing unit is connected between the first electrode plate and the second electrode plate; When solder migrates to the capacitance sensing unit, the capacitance value of the capacitance sensing unit changes, and the capacitance value of the capacitance sensing unit is used to indicate the working state of the circuit board. A conductive structure is provided, which connects the circuit board and the capacitive sensing unit. The conductive structure is used to electrically connect with external devices to transmit signals from the capacitive sensing unit.

2. The circuit board according to claim 1, characterized in that, When the capacitance value of the capacitor sensing unit is greater than or equal to a preset value, the circuit board is identified as having an abnormal operating state. When the capacitance value of the capacitor sensing unit is less than the preset value, the circuit board is identified as being in normal working condition.

3. The circuit board according to claim 1 or 2, characterized in that, The conductive structure is located between the first electrode plate and the second electrode plate; The conductive structure includes a wire assembly, which includes two wires running along the direction from the first electrode plate to the second electrode plate. There is a gap between the two wires. The wires connect the circuit board and the capacitive sensing part, and one end of the wire exposes the capacitive sensing part.

4. The circuit board according to claim 3, characterized in that, The circuit board includes multiple sets of wire groups, including a first wire group and a second wire group. The first wire group is closer to the first electrode plate than the second electrode plate, and the second wire group is closer to the second electrode plate than the first electrode plate.

5. The circuit board according to claim 1 or 2, characterized in that, Along the thickness direction of the circuit substrate, the heights of the first electrode plate and the second electrode plate are both less than or equal to the height of the capacitive sensing part.

6. The circuit board according to claim 1 or 2, characterized in that, The circuit board includes: A conductive layer is provided with a first groove and a second groove on the same side of the conductive layer. A first electrode plate is provided in the first groove, and a second electrode plate is provided in the second groove. A portion of the capacitive sensing part is provided in the opening of the first groove, and another portion of the capacitive sensing part is provided in the opening of the second groove. A first adhesive layer is disposed in the first groove, and the first adhesive layer is used to connect the conductive layer, the first electrode plate and the capacitive sensing part; A second adhesive layer is disposed in the second groove, and the second adhesive layer is used to connect the conductive layer, the second electrode plate and the capacitive sensing part.

7. A screen assembly, characterized in that, include: Screen itself; and The circuit board as described in any one of claims 1 to 6, wherein the circuit board is located on one side of the screen body.

8. An electronic device, characterized in that, include: case; and The screen assembly as claimed in claim 7, wherein the screen assembly is disposed on the housing.

9. The electronic device according to claim 8, characterized in that, Also includes: Controller; An alarm device, both the alarm device and the circuit board are electrically connected to the controller, which controls the operation of the alarm device based on the capacitance value of the capacitive sensing unit.

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