Low-cost PCB with anti-ESD performance
By adding a layer of white oil or green oil near the sensitive devices of the PCB board, the problems of increased PCB board volume and cost in the existing technology are solved, and the high-efficiency anti-ESD performance is improved at low cost.
Patent Information
- Application Number
- CN202422479575.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-12
- Publication Date
- 2025-09-19
- Estimated Expiration
- 2034-10-12
AI Technical Summary
When designing the anti-static performance of existing PCB boards, it is often necessary to add light guides or place signal traces on the inner layer, which increases the board size and cost, making it difficult to improve the anti-electrostatic discharge (ESD) performance without increasing costs.
An additional layer of white oil or green oil is added near the circuits of the sensitive device MIC chip and the light sensing chip to increase the equivalent air gap between the components, improve the electrical breakdown threshold, and prevent the electric field strength from reaching the breakdown threshold.
Without significantly increasing costs, the PCB board's ESD resistance is significantly improved. By increasing the equivalent air gap to isolate sensitive signals, the electric field strength is prevented from reaching the electrical breakdown threshold.
Smart Images
Figure CN223364307U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of electrostatics of PCBs, in particular to a low-cost PCB board with anti-ESD performance. Background Art
[0002] A printed circuit board (PCB) is a support for electronic components and serves as the electrical connection mechanism. Because it is manufactured using electronic printing technology, it is called a "printed" circuit board. The consistency of similar boards in electronic devices eliminates manual wiring errors and enables automated insertion or placement of electronic components, automated soldering, and automated testing, ensuring the quality of electronic equipment, improving productivity, reducing costs, and facilitating maintenance.
[0003] Static electricity is everywhere, and it has the following adverse effects on electronic components: 1. Electrostatic discharge or current generates heat, which can potentially damage components. 2. Electrostatic discharge generates an electromagnetic field with a large amplitude and a very wide spectrum, which can interfere with or even damage electronic components. 3. Electrostatic discharge damages components, causing them to be damaged and unable to work properly. It can be seen that the harm caused by static electricity is immeasurable.
[0004] With the widespread application of digital MICs and light-sensing ICs in electronic products, holes must be opened at the beginning of product ID design to meet the MIC pickup and light-sensing functions. However, these openings will inevitably introduce air gap issues (the distance required for charge to break through the air), which often poses challenges to the product's ESD protection performance.
[0005] Traditional designs often add light guides above the light-sensing IC or place the MIC's signal traces on the inner layer, but this also means a larger PCB board size and additional structural parts are required. Utility Model Content
[0006] When implementing anti-static design on existing PCB products, light guides are often added above the photosensitive IC or the MIC signal traces are placed on the inner layer, resulting in a larger PCB board size and requiring more structural parts, which drives up costs.
[0007] To address the above issues, a low-cost PCB with ESD resistance is proposed. By adding an additional layer of white oil and / or green oil near the circuits of the PCB's sensitive devices, the MIC chip and the light-sensing chip, sensitive signals can be isolated to increase the equivalent air gap between any components that may cause discharge. This prevents the electric field strength from reaching the electrical breakdown threshold without significantly increasing product costs, thereby improving the PCB's ESD resistance.
[0008] In a first aspect, a low-cost PCB board with ESD resistance performance comprises:
[0009] Sensitive devices;
[0010] First side;
[0011] Second side;
[0012] The sensitive device is welded on the first surface, and an opening is provided on the second surface of the PCB board corresponding to the sensitive device;
[0013] The sensitive device obtains a signal through the opening;
[0014] The PCB board also includes a solder resist layer;
[0015] A green oil layer is provided on the sensitive device area of the solder resist layer on the first surface.
[0016] In conjunction with the low-cost PCB board with ESD resistance described in the first aspect of the present invention, in a first possible implementation manner, the sensitive device includes a mic chip and a photosensitive chip.
[0017] In combination with the first possible implementation manner of the first aspect of the present utility model, in a second possible implementation manner, the dielectric constant of the green oil layer is 4 to 4.8, and the breakdown field strength thereof is 100 KV / mm.
[0018] In a second aspect, a low-cost PCB board with ESD resistance performance includes:
[0019] Sensitive devices;
[0020] First side;
[0021] Second side;
[0022] The sensitive device is welded on the first surface, and an opening is provided on the second surface of the PCB board corresponding to the sensitive device;
[0023] The sensitive device obtains a signal through the opening;
[0024] The PCB board also includes a silk screen layer;
[0025] A white oil layer is provided on the sensitive device region of the silk-screen layer on the first surface.
[0026] In conjunction with the low-cost PCB board with ESD resistance described in the second aspect of the present invention, in a first possible implementation manner, the sensitive device includes a mic chip and a photosensitive chip.
[0027] In combination with the first possible implementation manner of the second aspect of the present utility model, in a second possible implementation manner, the dielectric constant of the white oil layer is 4 to 4.8, and the breakdown field strength thereof is 100 KV / mm.
[0028] In a third aspect, a low-cost PCB board with ESD resistance performance includes:
[0029] Sensitive devices;
[0030] First side;
[0031] Second side;
[0032] The sensitive device is welded on the first surface, and an opening is provided on the second surface of the PCB board corresponding to the sensitive device;
[0033] The sensitive device obtains a signal through the opening;
[0034] The PCB board also includes a solder resist layer and a silk screen layer;
[0035] A green oil layer is attached to the sensitive device area of the solder resist layer on the first surface, and a white oil layer is attached to the sensitive device area of the silk screen layer on the first surface.
[0036] In conjunction with the low-cost PCB board with ESD resistance described in the third aspect of the present invention, in a first possible implementation manner, the sensitive device includes a mic chip and a photosensitive chip.
[0037] In combination with the first possible implementation manner of the third aspect of the present utility model, in a second possible implementation manner, the thickness of the white oil layer or the green oil layer is 8-15 microns.
[0038] In combination with the second possible implementation manner of the third aspect of the present utility model, in a third possible implementation manner, the dielectric constant of the white oil layer or the green oil layer is 4 to 4.8, and the breakdown field strength thereof is 100 KV / mm.
[0039] The low-cost PCB board with ESD resistance described in the present invention is implemented by adding an additional layer of white oil and / or green oil near the circuits of the sensitive devices MIC chip and light sensor chip of the PCB board to isolate sensitive signals and increase the equivalent air gap between any components that may cause discharge. This prevents the electric field strength from reaching the electrical breakdown threshold without significantly increasing product costs, thereby improving the ESD resistance of the PCB board. BRIEF DESCRIPTION OF THE DRAWINGS
[0040] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.
[0041] Figure 1 This is a schematic diagram of the main structural layout of a low-cost PCB board with ESD resistance in the present invention;
[0042] Figure 2 This is a schematic diagram of the rear view structure layout of a low-cost PCB board with ESD resistance in the present invention;
[0043] Figure 3 Schematic diagram of the cross-sectional structure of Example 1 of a low-cost PCB board with ESD resistance in the present utility model;
[0044] Figure 4 Schematic diagram of the cross-sectional structure of Example 2 of a low-cost PCB board with ESD resistance in the present utility model;
[0045] Figure 5 This is a schematic cross-sectional structure diagram of Example 3 of a low-cost PCB board with ESD resistance in the present invention. DETAILED DESCRIPTION
[0046] The following is a clear and complete description of the technical solutions of the present invention in conjunction with the accompanying drawings. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, other embodiments obtained by ordinary technicians in this field without creative work are all within the scope of protection of the present invention.
[0047] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention pertains. The terms used herein in the specification of this invention are intended only to describe specific embodiments and are not intended to limit the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.
[0048] It should be noted that when an element is referred to as being “fixed on” or “disposed on” another element, it may be directly on the other element or indirectly on the other element. When an element is referred to as being “connected to” another element, it may be directly connected to the other element or indirectly connected to the other element.
[0049] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and 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, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.
[0050] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. Throughout the description of this application, "plurality" means two or more, unless otherwise specifically defined.
[0051] In the anti-static design of existing PCB board 100 products, a light guide is often added above the photosensitive IC or the signal trace of the MIC is placed on the inner layer, which results in a larger volume of the PCB board 100 and requires more structural parts, thereby increasing the cost.
[0052] To address the above problems, a low-cost PCB board 100 with ESD resistance is proposed.
[0053] Example 1
[0054] First, as Figure 1 , Figure 1 Schematic diagram of the main view of the structure layout of a low-cost PCB board 100 with ESD resistance in the present invention; A low-cost PCB board 100 with ESD resistance includes a sensitive device 110, a first surface, and a second surface; The sensitive device 110 is soldered on the first surface, and an opening 120 is provided on the second surface of the PCB board 100 corresponding to the sensitive device 110; Figure 2 , Figure 2 The following is a schematic diagram of the rear view of a low-cost PCB board 100 with ESD resistance in the present invention; the sensitive device 110 obtains a signal through an opening 120; the PCB board 100 also includes a solder mask layer 102; a green oil layer 104 is attached to the sensitive device 110 area of the solder mask layer 102 on the first side. By adding an additional layer of white oil or green oil near the circuit of the sensitive device 110 MIC chip and the light sensor chip on the PCB board 100, the sensitive signal can be isolated to increase the equivalent air gap between any components that may cause discharge. Without significantly increasing product cost, the electric field strength is prevented from reaching the electrical breakdown threshold, thereby improving the ESD resistance of the PCB board 100. Figure 3 , Figure 3 Schematic diagram of the cross-sectional structure of Example 1 of a low-cost PCB board 100 with ESD resistance in the present invention.
[0055] Figure 3 、 Figure 4 and Figure 5 101 is the main layer of the PCB.
[0056] In this embodiment, the sensitive device 110 includes a MIC chip and a photosensitive chip. The dielectric constant of the green oil layer 104 is 4-4.8, and the breakdown field strength is 100KV / mm.
[0057] When the electric field strength applied to the dielectric increases to a certain level, the dielectric suddenly changes from an insulating state to a conductive state. This transition phenomenon is called dielectric breakdown.
[0058] In this embodiment, different dielectric parameters of different materials have different corresponding breakdown strengths. On the PCB, a green oil layer 104 is attached to the solder mask layer 102 at the NC pin or ground area of the sensitive device 110 to increase the equivalent air gap for electrical breakdown.
[0059] Air gap: The distance required for electric charge to break through air. In the product, it specifically refers to the equivalent distance from the MIC pickup hole or the light-sensing IC light-transmitting hole in the housing to the MIC chip and light-sensing chip on the PCB board 100.
[0060] The discharge medium from the MIC pickup hole and the photosensitive hole of the light-sensing chip to the silk-screen layer 103 of the PCB is air. The relative dielectric constant of air is 1, and the electric breakdown field strength is 3 kV / mm. It is determined by the product ID and usually does not change.
[0061] In this embodiment, a green ink layer 104 (ink) is applied to the solder mask layer 102 corresponding to the MIC chip or photosensitive chip. Its relative dielectric constant is 4-4.8, and its breakdown field strength is approximately 100 kV / mm. Typically, a layer of ink with a thickness of 10 μm can effectively increase the voltage withstand strength by 100 kV / mm * 10 μm = 1 kV, thereby improving ESD resistance.
[0062] Example 2
[0063] In the second aspect, a low-cost PCB board 100 with ESD resistance is provided. Figure 4 , Figure 4This is a schematic cross-sectional structure diagram of Example 2 of a low-cost PCB board 100 with ESD resistance in the present invention, including a sensitive device 110, a first surface, and a second surface; the sensitive device 110 is soldered on the first surface, and an opening 120 is provided on the second surface of the PCB board 100 corresponding to the sensitive device 110; the sensitive device 110 obtains a signal through the opening 120; the PCB board 100 also includes a silk screen layer 103; a white oil layer 105 is attached to the sensitive device 110 area of the silk screen layer 103 on the first surface.
[0064] In this embodiment, the sensitive device 110 includes a MIC chip and a photosensitive chip. The dielectric constant of the white oil layer 105 is 4-4.8, and the breakdown field strength is 100KV / mm.
[0065] In this embodiment, different materials have different dielectric parameters and corresponding breakdown strengths, and a layer of white oil is added to the silk screen layer 103 of the NC pin or ground area of the sensitive device 110 on the PCB to increase the equivalent air gap for electrical breakdown.
[0066] The discharge medium from the MIC pickup hole and the photosensitive hole of the light-sensing chip to the silk-screen layer 103 of the PCB is air. The relative dielectric constant of air is 1, and the electric breakdown field strength is 3 kV / mm. It is determined by the product ID and usually does not change.
[0067] In this embodiment, a white ink layer 105 (ink) is applied to the silkscreen layer 103 corresponding to the MIC chip or photosensitive chip. Its relative dielectric constant is 4-4.8, and its breakdown field strength is approximately 100 kV / mm. Typically, a layer of ink with a thickness of 10 μm can effectively increase the voltage withstand strength by 100 kV / mm * 10 μm = 1 kV, thereby improving ESD resistance.
[0068] Example 3
[0069] Thirdly, as Figure 5 , Figure 5 The cross-sectional structure of Example 3 of a low-cost PCB 100 with ESD resistance according to the present invention is schematically shown. The low-cost PCB 100 with ESD resistance comprises a sensitive device 110, a first surface, and a second surface. The sensitive device 110 is soldered to the first surface, and an opening 120 is provided on the second surface of the PCB 100 corresponding to the sensitive device 110. The sensitive device 110 obtains signals through the opening 120. The PCB 100 also comprises a solder mask layer 102 and a silk screen layer 103. A green oil layer 104 is provided on the first surface of the solder mask layer 102 in the area of the sensitive device 110, and a white oil layer 105 is provided on the first surface of the silk screen layer 103 in the area of the sensitive device 110.
[0070] In this embodiment, the sensitive device 110 includes a MIC chip and a photosensitive chip. The dielectric constant of the white oil layer 105 and the green oil layer 104 is 4-4.8, and the breakdown field strength is 100KV / mm.
[0071] The discharge medium from the MIC pickup hole and the photosensitive hole of the light-sensing chip to the silk-screen layer 103 of the PCB is air. The relative dielectric constant of air is 1, and the electric breakdown field strength is 3 kV / mm. It is determined by the product ID and usually does not change.
[0072] In this embodiment, a green ink layer 104 (ink) is applied to the solder mask layer 102 corresponding to the MIC chip or photosensitive chip, and a white ink layer 105 (ink) is applied to the silkscreen layer 103. Each ink layer has a relative dielectric constant of 4 to 4.8, and a breakdown field strength of approximately 100 kV / mm. Typically, a layer of ink is 10 μm thick, which can effectively increase the voltage withstand strength by 100 kV / mm * 10 μm = 1 kV, thereby improving ESD resistance.
[0073] A low-cost PCB board 100 with ESD resistance is implemented according to the present invention. By adding an additional layer of white oil and / or green oil near the circuits of the sensitive device 110 MIC chip and the light-sensing chip of the PCB board 100, sensitive signals can be isolated to increase the equivalent air gap between any components that may cause discharge. This prevents the electric field strength from reaching the electrical breakdown threshold without significantly increasing the product cost, thereby improving the ESD resistance of the PCB board 100.
[0074] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.
Claims
1. A low-cost PCB board with ESD resistance, characterized by comprising: Sensitive devices; First side; Second side; The sensitive device is welded on the first surface, and an opening is provided on the second surface of the PCB board corresponding to the sensitive device; The sensitive device obtains a signal through the opening; The PCB board also includes a solder resist layer; A green oil layer is provided on the sensitive device area of the solder resist layer on the first surface.
2. The low-cost PCB board with ESD resistance according to claim 1, characterized in that: The sensitive devices include a MIC chip and a photosensitive chip.
3. The low-cost PCB board with ESD resistance according to claim 2, characterized in that: The dielectric constant of the green oil layer is 4-4.8, and the breakdown field strength thereof is 100KV / mm.
4. A low-cost PCB board with ESD resistance, characterized in that: include: Sensitive devices; First side; Second side; The sensitive device is welded on the first surface, and an opening is provided on the second surface of the PCB board corresponding to the sensitive device; The sensitive device obtains a signal through the opening; The PCB board also includes a silk screen layer; A white oil layer is provided on the sensitive device region of the silk-screen layer on the first surface.
5. The low-cost PCB board with ESD resistance according to claim 4, characterized in that: The sensitive devices include a MIC chip and a photosensitive chip.
6. The low-cost PCB board with ESD resistance according to claim 5, characterized in that: The dielectric constant of the white oil layer is 4-4.8, and the breakdown field strength thereof is 100KV / mm.
7. A low-cost PCB board with ESD resistance, characterized in that: include: Sensitive devices; First side; Second side; The sensitive device is welded on the first surface, and an opening is provided on the second surface of the PCB board corresponding to the sensitive device; The sensitive device obtains a signal through the opening; The PCB board also includes a solder resist layer and a silk screen layer; A green oil layer is attached to the sensitive device area of the solder resist layer on the first surface, and a white oil layer is attached to the sensitive device area of the silk screen layer on the first surface.
8. The low-cost PCB board with ESD resistance according to claim 7, characterized in that: The sensitive devices include a MIC chip and a photosensitive chip.
9. The low-cost PCB board with ESD resistance according to claim 8, characterized in that: The thickness of the white oil layer or the green oil layer is 8-15 microns.
10. The low-cost PCB board with ESD resistance according to claim 9, characterized in that: The dielectric constant of the white oil layer or the green oil layer is 4-4.8, and the breakdown field strength thereof is 100KV / mm.