PCBA with encapsulation protection layer

Abstract

The application discloses a PCBA with a packaging protective layer, comprising: a PCB; electronic components arranged on the PCB; and a UV-cured insulating protective layer fixedly bonded to the PCB and covering at least part of the electronic components. The UV-cured insulating protective layer covers and protects the connection between the at least part of the electronic components and the PCB, and preferably, the UV-cured insulating protective layer also covers the upper surface of the at least part of the electronic components.

Description

Technical Field

[0001] This application relates to the field of semiconductor packaging technology, and in particular to a PCBA with a packaging protection layer, which is especially suitable for electronic devices with high requirements for three-proof performance (moisture-proof, salt spray-proof, and mildew-proof) and structural reliability, such as electric drive circuit boards, power supply circuit boards, electronic control circuit boards and electromagnetic circuit boards in the fields of industrial control, automotive electronics, and new energy equipment. Background Technology

[0002] PCBA (Printed Circuit Board Assembly) is a core component of electronic devices, consisting of a printed circuit board (PCB) and various electronic components soldered onto it. During PCBA use, the operating environment is often complex, potentially facing adverse factors such as humidity, salt spray, mold, dust, and vibration. Among these, the connections between electronic components and the PCB (such as solder joints and pins) are the weakest points in the PCBA. Once exposed to external environmental corrosion or mechanical stress, problems such as poor contact and corrosion failure can easily occur, leading to the malfunction of the entire electronic device.

[0003] To improve the reliability and lifespan of PCBAs, the industry typically employs conformal coating processes. Traditional conformal coating methods mainly include coating, potting, and dip coating. Coating involves applying conformal coatings (such as acrylates, silicone rubber, and polyurethane) to the PCBA surface via spraying or brushing to form a protective film. Potting involves injecting liquid potting material into the housing or specific areas containing the PCBA, which then cures to form a sealed structure. Dip coating involves immersing the PCBA in conformal coating, removing it, and allowing it to cure to form a protective film.

[0004] However, existing tri-proof protection technologies have many shortcomings: Insufficient targeted protection: Traditional coating or dip coating processes mostly provide overall coverage, failing to provide differentiated protection based on the height of electronic components, their importance, and the environmental sensitivity of their location. For taller components, their connections to the PCB (solder joints) are often difficult to cover adequately; while for shorter components, over-coverage may lead to poor heat dissipation or unnecessary increased costs.

[0005] Poor controllability of protective layer precision: The edges of protective layers formed by traditional processes are often irregular in shape, especially in areas with densely packed complex components. This can easily lead to problems such as coatings that are too thick or too thin, missed coatings, or accumulation. Insufficient edge precision may result in reduced adhesion between the protective layer and components or the PCB, and may even cause peeling under vibration.

[0006] Limited process adaptability: For PCBAs that assemble multiple surface-mount electronic components, traditional processes struggle to meet the protection requirements of components with different mounting methods. Surface-mount components are small and densely distributed, requiring precise coverage of solder joints by the protective layer; surface-mount components are relatively tall, and their root solder joints require special protection, but the top usually does not need to be completely covered, otherwise it may affect heat dissipation or subsequent testing.

[0007] The contradiction between thickness and structural stability: When a thicker protective layer is required to improve protective performance, uneven shrinkage is prone to occur during the curing process of traditional coatings, which can lead to cracking of the protective layer or peeling off from the PCB and components; however, if the thickness is reduced, the requirements for high protection levels cannot be met.

[0008] Material and process matching issues: Some conformal coatings require high-temperature curing, which may damage heat-sensitive components on PCBAs; while room-temperature curing materials have problems such as long curing time and low production efficiency.

[0009] As electronic devices evolve towards miniaturization, high integration, and high reliability, higher demands are placed on PCBA (Printed Circuit Board Assembly) protection technology. There is an urgent need for a PCBA packaging protection structure that can achieve precise and differentiated protection, possesses strong process controllability, and adapt to different types of components and operating environments. Summary of the Invention

[0010] To address the shortcomings of existing PCBA conformal protection technologies, such as insufficient targeting, poor precision controllability, and limited process adaptability, this invention provides a PCBA with a protective encapsulation layer. The aim is to achieve precise and differentiated protection for the PCBA through the structural design and process optimization of the UV-cured insulating protective layer, thereby improving the reliability of electronic component connections, enhancing the conformal protection performance of the PCBA, and improving the process controllability and structural stability of the protective layer.

[0011] To achieve the above objectives, the present invention adopts the following technical solution: A PCBA with a protective encapsulation layer includes a PCB, electronic components disposed on the PCB, and a UV-curable insulating protective layer fixedly bonded to the PCB, wherein the UV-curable insulating protective layer at least partially covers the electronic components.

[0012] Furthermore, the UV-cured insulating protective layer covers and protects at least part of the connection between the electronic components and the PCB; preferably, the UV-cured insulating protective layer also covers at least part of the upper surface of the electronic components. The connection between the electronic components and the PCB (such as solder joints and leads) is the core weak point of the PCBA. Covering and protecting it can effectively isolate it from corrosive media such as moisture and salt spray, while reducing the impact of mechanical stress such as vibration on the connection; covering the upper surface of the electronic components can further improve the overall protection effect, especially suitable for harsh environments.

[0013] Furthermore, the UV-cured insulating protective layer is formed by layer-by-layer spraying and photocuring, and the UV-cured insulating protective layer also covers at least a portion of the PCB area. The layer-by-layer spraying and photocuring process, by controlling the thickness and range of each spray, and rapidly curing under UV light, allows for precise control of the protective layer's thickness and shape; covering part of the PCB surface enhances the bonding area between the protective layer and the PCB, improving overall structural stability, while also protecting exposed areas of the PCB.

[0014] Furthermore, the UV-cured insulating protective layer completely covers at least a portion of the electronic components; preferably, at least a portion of the electronic components are surface-mount electronic components, and the UV-cured insulating protective layer covers at least a portion of these surface-mount electronic components. For small-sized and low-height electronic components (especially surface-mount electronic components), complete coverage provides all-around protection, preventing the intrusion of external dust and moisture; complete coverage of densely packed surface-mount electronic components also reduces interference between adjacent components, improving the stability of the PCBA.

[0015] Furthermore, the UV-cured insulating protective layer encapsulates and protects the connection points between electronic components taller than 5mm and the PCB. Electronic components taller than 5mm (such as surface mount capacitors and inductors) typically have a higher center of gravity, experience greater stress at their connection points under vibration, and are prone to moisture accumulation at their solder joints. Targeted encapsulation and protection can significantly improve the connection reliability of such components.

[0016] Furthermore, the UV-curable insulating protective layer on the PCB has multiple independently spaced encapsulation areas. Based on the distribution, functional zoning, and protection requirements of electronic components on the PCBA, dividing the UV-curable insulating protective layer into multiple independent encapsulation areas enables differentiated protection—thicker or more comprehensive encapsulation is used for highly sensitive areas (such as high-voltage, high-current, and high-heat-generating areas), while simplified encapsulation is used for low-sensitivity areas, reducing material consumption and process costs while ensuring protective effectiveness.

[0017] Furthermore, the UV-cured insulating protective layer completely encapsulates electronic components with a height of less than 2mm, or the UV-cured insulating protective layer completely encapsulates electronic components with a height of less than 1mm. Electronic components with a height of less than 2mm (or 1mm) (such as surface mount resistors, capacitors, chips, etc.) are small in size and low in height. Complete encapsulation will not significantly affect the overall thickness and heat dissipation performance of the PCBA, and can achieve efficient protection, which is especially suitable for miniaturized equipment with high space requirements.

[0018] Furthermore, the UV-cured insulating protective layer has an upper surface and a circumferential side edge surface surrounding the upper surface; the circumferential side edge surface is a controllable regular surface. By optimizing the spraying path and UV curing parameters, the circumferential side edge surface is made into a regular shape (such as a flat, continuous surface), avoiding stress concentration or protection gaps caused by irregular edges in traditional processes, and improving the structural stability and protective reliability of the protective layer.

[0019] Furthermore, when the thickness is 300 micrometers or more, the circumferential side edge surface is perpendicular to the PCB surface; preferably, the longitudinal section of the circumferential side edge surface is a diagonal line or a vertical line. When the protective layer thickness reaches 300 micrometers or more, the circumferential side edge perpendicular to the PCB surface can reduce stress accumulation in the edge area and reduce the risk of cracking; the design of a diagonal or vertical line longitudinal section can be precisely controlled by process parameters. The diagonal design is suitable for areas requiring gradient transitions, while the vertical line design is suitable for areas requiring clear boundaries.

[0020] Furthermore, the height of the circumferential edge surface is less than 5mm. Controlling the height of the circumferential edge surface can avoid increasing the overall size of the PCBA due to excessively high protective layers, while reducing the risk of interference with surrounding structures, making it suitable for scenarios with strict limitations on installation space.

[0021] Furthermore, the PCBA includes one or more of the following: electric drive circuit board, power supply circuit board, electronic control circuit board, and electromagnetic circuit board. Preferably, the voltage, current, or heat generation of the electronic components covered by the UV-cured insulating protective layer and the adjacent PCB area has a greater voltage difference, current difference, or heat generation difference than other areas of the PCB. Electric drive, power supply, electronic control, and electromagnetic circuit boards often have high-voltage, high-current, or high-heat generation areas. Electronic components and connections in these areas are more susceptible to failure due to environmental influences. Targeted coverage with the UV-cured insulating protective layer can significantly improve their reliability and ensure the stable operation of the circuit board.

[0022] Compared with the prior art, the present invention has the following beneficial effects: Precise protection: By designing the coverage area (partial or complete coverage) of the UV-cured insulating protective layer, the encapsulation area (independently spaced), and key protected objects (such as the connection points or the entirety of high / low height components), differentiated protection for PCBA is achieved. This addresses the protection needs of different types and heights of electronic components, especially strengthening the protection at the connection points between electronic components and the PCB, significantly reducing the failure risk of this weak link.

[0023] High process controllability: The UV-cured insulating protective layer adopts a layer-by-layer spraying and photocuring process, which can precisely control the thickness, shape, and regularity of the circumferential edge surface (such as verticality and longitudinal cross-sectional shape) of the protective layer, avoiding problems such as uneven coating and irregular edges in traditional coating processes. UV curing is fast and does not require high temperature, which can reduce damage to heat-sensitive components and improve production efficiency and product consistency.

[0024] High structural stability: The circumferential edge surface is a controllable and regular surface, and when the thickness is more than 300 micrometers, it is perpendicular to the PCB surface, which reduces stress concentration in the edge area and reduces the risk of cracking or peeling of the protective layer; the protective layer is fixedly bonded to the PCB and at least covers part of the PCB area, which enhances the bonding force between the two and improves the overall stability of the PCBA structure.

[0025] Wide range of applications: Applicable to various types of PCBAs such as electric drive circuit boards, power supply circuit boards, electronic control circuit boards, and electromagnetic circuit boards. Especially suitable for PCBAs in areas with high voltage difference, large current difference, or large heat generation difference. The design parameters of the protective layer can be flexibly adjusted according to the characteristics of different circuit boards to meet diverse protection needs.

[0026] Enhanced three-proof performance: The continuous and dense protective film formed by the UV-cured insulating protective layer can effectively block corrosive media such as moisture, salt spray, mold and dust, significantly improving the moisture-proof, salt spray-proof and mold-proof performance of PCBA, extending the service life of electronic equipment and reducing maintenance costs. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a typical circuit board (PCBA) structure diagram; Figure 2 This is a PCBA structure diagram with a packaging protection layer provided in one embodiment of this application; Figure 3 This is a PCBA structure diagram with a packaging protection layer provided in another embodiment of this application; Figure 4 This is a PCBA structure diagram with a packaging protection layer provided in another embodiment of this application.

[0029] Explanation of reference numerals in the attached figures: 1. PCB; 10. PCB mounting surface; 2. Electronic components; 2a. First electronic component; 2b. Second electronic component; 2c. Third electronic component; 2d. Fourth electronic component; 3. UV-cured insulating protective layer; 31. Circumferential side edge surface; 32. Top surface; 3a. First UV-cured insulating protective layer (semi-enclosed type); 3b. Second UV-cured insulating protective layer; 3c. Third UV-cured insulating protective layer; 3d. Fourth UV-cured insulating protective layer; 3f. Fifth UV-cured insulating protective layer. Detailed Implementation

[0030] To enable those skilled in the art to better understand the technical solutions of this invention, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this invention.

[0031] It should be noted that when an element is referred to as being "set on" another element, it can be directly on the other element or may be interposed with another element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or may be interposed with another element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementations.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items. Example

[0033] Combination Figure 2As shown, this embodiment provides a PCBA with a protective encapsulation layer, including a PCB1, electronic components 2, and a UV-curable insulating protective layer 3. The PCB1 can be a conventional FR-4 material printed circuit board, with a PCB mounting surface 10 for supporting the electronic components 2 and the UV-curable insulating protective layer 3.

[0034] The electronic components include a first electronic component 2a, a second electronic component 2b, a third electronic component 2c, and a fourth electronic component 2d, all of which are fixed to the PCB mounting surface 10 of PCB1 by soldering. Specifically, the first electronic component 2a is a surface-mount chip with a height greater than 5mm (approximately 4mm), and its connection to PCB1 is a critical solder joint; the second electronic component 2b is a surface-mount inductor with a height less than 2mm (approximately 1.5mm); the third electronic component 2c is a surface-mount resistor with a height less than 1mm (approximately 0.8mm); and the third electronic component 2d is a surface-mount semiconductor device with a height of at least 4mm (approximately 4.8mm).

[0035] The UV-cured insulating protective layer 3 is made of UV-cured acrylic insulating material and is formed by a layer-by-layer spraying and light curing process. It includes a first UV-cured insulating protective layer 3a (semi-enclosed type), a second UV-cured insulating protective layer 3b, and a third UV-cured insulating protective layer 3c, which are mutually spaced and independent encapsulation areas.

[0036] The first UV-cured insulating protective layer 3a is a semi-enclosed type, primarily covering the connection point (solder joint) between the first electronic component 2d (surface mount semiconductor device) and PCB1, extending upwards to cover a 5mm height above this connection point, but not completely covering the top of the first electronic component 2d to avoid affecting its heat dissipation performance. This design reinforces the weak connection points of tall components while also considering heat dissipation requirements. Alternatively, it can be... Figure 4 As shown, the fifth UV-cured insulating protective layer 3f mainly covers the pins of the first electronic component 2a (surface chip) and PCB1, and the fifth UV-cured insulating protective layer 3f is lower than the top of the first electronic component 2d. At this time, the top of the first electronic component 2d is exposed, and the pin connection is protected, forming a three-proof protection.

[0037] The second UV-cured insulating protective layer 3b completely covers the second electronic component 2b (surface mount inductor). Its coverage extends from the PCB mounting surface 10 to the upper surface of the surface mount inductor and extends outward to a 0.5mm perimeter of the surface mount inductor on the PCB, forming all-around protection for the surface mount inductor. The protective layer is 400 micrometers thick, and its circumferential side edge surface 31 is perpendicular to the PCB 1 surface, with a vertical cross-section, ensuring the accuracy, regularity, and structural stability of the package edge position.

[0038] The third UV-cured insulating protective layer 3c completely covers the third electronic component 2c (chip resistor), covering the entire chip resistor and the surrounding 0.3mm PCB area. The protective layer is 300 micrometers thick, and the longitudinal section of the circumferential side edge surface 31 is a diagonal line (slope 1:2), which reduces edge stress through gradient transition.

[0039] Each UV-curable insulating protective layer (3a, 3b, 3c, 3d, 3f) is formed by layer-by-layer spraying: the thickness of each spray layer is controlled between 10-50 micrometers, and UV lamp irradiation is applied immediately after spraying. The spraying-curing process is repeated until the designed thickness is achieved. This process ensures that the protective layer is bubble-free, highly dense, and has excellent adhesion strength to PCB1 and electronic components 2. For example, each UV-curable insulating protective layer can be formed by layer-by-layer spraying and curing using the PCBA board packaging equipment disclosed in CN116321788B applied for by Suzhou Connie Electronics Technology Co., Ltd.

[0040] In this embodiment, the area covered by the UV-cured insulating protective layer is the power output area of ​​the power circuit board. The operating current (10-20A), voltage difference (50-200V), and heat generation (surface temperature up to 60°C) of the electronic components in this area are significantly higher than those in other areas of the PCB. Through targeted encapsulation protection, the three-proof performance of this area (tested to show no corrosion after 48 hours of salt spray testing and insulation resistance ≥100MΩ after 96 hours of damp heat testing) is more than 3 times better than that of the unprotected area. Example

[0041] Combination Figure 3 As shown, this embodiment provides another PCBA with a protective encapsulation layer, which is suitable for electronic control circuit boards. Its structure includes PCB1, electronic components 2 and UV-cured insulating protective layer 3.

[0042] PCB1 uses a high Tg value (170℃) PCB substrate to adapt to high operating temperature environments. Electronic components 2 include multiple surface mount chips (1.2mm high), surface mount inductors (2.5mm high), and surface mount diodes (7mm high), all soldered to the PCB mounting surface 10 of PCB1. The UV-curable insulating protective layer 3 uses UV-curable silicone rubber insulating material (temperature resistance -40℃ to 150℃), formed by layer-by-layer spraying and photocuring. The UV-curable insulating protective layer 3 includes a fourth UV-curable insulating protective layer 3d, which is a continuous integral structure, but with differentiated designs in component areas of different heights.

[0043] For surface mount chips and surface mount inductors with a height of less than 2mm, the fourth UV-cured insulating protective layer 3d completely covers them. The upper surface 32 is flush with the top of the component, and the thickness of the protective layer gradually transitions from the PCB surface to the top of the component (200-500 micrometers). The longitudinal section of the circumferential side edge surface 31 is a vertical line, perpendicular to the PCB surface, with a height of 2.5mm (less than 5mm).

[0044] For surface-mount diodes with a height greater than 5 mm, the fourth UV-cured insulating protective layer 3d only covers the connection point (solder joint) with PCB1 and a 2 mm height range at the base, forming a semi-enclosed protection to prevent heat dissipation obstruction caused by an excessively high protective layer. The protective layer thickness in this area is 600 micrometers, and the longitudinal section of the circumferential edge surface 31 is vertical, enhancing the adhesion between the edge and the PCB. In other embodiments, the longitudinal section of the circumferential edge surface 31 is oblique; for example, the longitudinal section of the entire UV-cured insulating protective layer 3 is trapezoidal.

[0045] The fourth UV-cured insulating protective layer 3d also covers the area on PCB1 where no components are installed (approximately 30% of the total PCB area). These areas are densely populated with circuit traces, and the protective layer enhances their insulation performance and corrosion resistance.

[0046] In this embodiment, the PCBA is the signal processing area of ​​the electronic control circuit board. The voltage difference of the electronic components in this area is small (≤30V), but the requirements for signal integrity are high, and the working environment is subject to slight vibration (frequency 10-2000Hz). Testing showed that after a vibration test (10-2000Hz frequency sweep, acceleration 10g), the PCBA with a 3d fourth UV-cured insulating protective layer exhibited no solder joint detachment of any electronic components, and the change rate of electrical performance parameters was ≤1%, significantly better than the unprotected PCBA (parameter change rate ≥5%). Example

[0047] This embodiment provides a PCBA with a protective encapsulation layer suitable for electromagnetic circuit boards. Its structure is similar to that of Embodiment 1, with the main difference being the material of the UV-curable insulating protective layer and the design of the encapsulation area. Specifically, the UV-curable insulating protective layer 3 is made of UV-curable polyurethane material, suitable for insulation protection requirements in electromagnetic environments.

[0048] Based on the functional partitioning of the electromagnetic circuit board, the UV-cured insulating protective layer is divided into five independently spaced encapsulation areas, corresponding to the power module, filtering module, amplification module, control module, and interface module, respectively. Among these, the electronic components (such as electrolytic capacitors, power inductors, and power chips) in the power module and filtering module are relatively tall (3-6mm) and are protected with a semi-enclosed design (only covering the connection points); the components (such as operational amplifiers and MCU chips) in the amplification module and control module are relatively short (0.5-1.5mm) and are fully enclosed; the connectors in the interface module are surrounded by a ring-shaped protective layer to enhance structural stability during insertion and removal.

[0049] The protective layer of the power module area is 500 micrometers thick, with a 3mm height on the circumferential side edge surface and a vertical straight line in the longitudinal section; the protective layer of the amplification module area is 300 micrometers thick, with a diagonal line (slope 1:3) on the longitudinal section of the circumferential side edge surface; each package area is spaced 0.5-1mm apart to avoid mutual interference.

[0050] In the electromagnetic compatibility (EMC) test, the UV-cured insulating protective layer of the PCBA in this embodiment effectively reduces electromagnetic interference between modules (radiated emissions are reduced by 6-10dB), while its insulation performance ensures safe isolation between high-voltage areas (220V AC input) and low-voltage areas (5V DC output), meeting the requirements of the IEC61010 safety standard.

[0051] In summary, this invention achieves precise and differentiated encapsulation protection for PCBAs by designing the structural features, coverage area, and process parameters of the UV-curable insulating protective layer. This effectively solves the problems of insufficient targeting and poor precision controllability in existing three-proof protection technologies. The PCBA with this encapsulation protective layer has advantages such as structural stability, excellent protective performance, strong process controllability, and wide applicability. It can significantly improve the reliability and service life of electronic devices, and has high practical value and market prospects.

[0052] Any numerical values ​​cited herein include all values ​​ranging from a lower limit to an upper limit, increasing by one unit, with at least two units between any lower and any higher value. For example, if the quantity of a component or the value of a process variable (e.g., temperature, pressure, time, etc.) is described as being from 1 to 90, preferably from 20 to 80, more preferably from 30 to 70, the purpose is to illustrate that values ​​such as 15 to 85, 22 to 68, 43 to 51, 30 to 32 are also explicitly listed in this specification. For values ​​less than 1, a unit is appropriately considered to be 0.0001, 0.001, 0.01, 0.1, etc. These are merely examples intended for explicit expression, and it can be assumed that all possible combinations of values ​​listed between the minimum and maximum values ​​are explicitly described in this specification in a similar manner.

[0053] Unless otherwise stated, all ranges include the endpoints and all numbers between them. The terms "approximately" or "about" used with ranges apply to both endpoints of the range. Thus, "approximately 20 to 30" is intended to cover "approximately 20 to approximately 30," including at least the specified endpoints.

[0054] All articles and references disclosed herein, including patent applications and publications, are incorporated herein by reference for various purposes. The term “substantially constitutes…” used to describe a combination should include the identified elements, components, parts, or steps, as well as other elements, components, parts, or steps that do not substantially affect the essential novelty of the combination. The use of the terms “comprising” or “including” to describe combinations of elements, components, parts, or steps herein also contemplates embodiments substantially constituted by such elements, components, parts, or steps. The use of the term “may” herein is intended to indicate that any described attribute included by “may” is optional.

[0055] Multiple elements, components, parts, or steps can be provided by a single integrated element, component, part, or step. Alternatively, a single integrated element, component, part, or step can be divided into multiple separate elements, components, parts, or steps. The use of "a" or "an" to describe an element, component, part, or step does not imply the exclusion of other elements, components, parts, or steps.

[0056] It should be understood that the above description is for illustrative purposes and not for limitation. Many embodiments and applications beyond the provided examples will be apparent to those skilled in the art upon reading the above description. Therefore, the scope of this teaching should not be determined by reference to the above description, but rather by reference to the appended claims and the full scope of their equivalents. For purposes of completeness, all articles and references, including patent applications and publications, are incorporated herein by reference. The omission of any aspect of the subject matter disclosed herein in the preceding claims is not intended as a waiver of that subject matter, nor should it be construed as an indication that the inventors have not considered that subject matter as part of the disclosed inventive subject matter.

Claims

1. A PCBA with a protective encapsulation layer, characterized in that, include: PCB; Electronic components disposed on the PCB; A UV-curable insulating protective layer is fixedly bonded to the PCB, which at least covers a portion of the electronic components; the UV-curable insulating protective layer covers and protects at least a portion of the connection between the electronic components and the PCB, and also covers at least a portion of the PCB area; the UV-curable insulating protective layer completely covers at least a portion of the electronic components.

2. The PCBA as described in claim 1, characterized in that, The UV-cured insulating protective layer will also cover at least part of the upper surface of the electronic components.

3. The PCBA as described in claim 1, characterized in that, The UV-cured insulating protective layer is formed by spraying and curing layer by layer.

4. The PCBA as described in claim 1, characterized in that, At least a portion of the electronic components are surface mount electronic components, and the UV-cured insulating protective layer covers at least a portion of the surface mount electronic components.

5. The PCBA as described in claim 1, characterized in that, The UV-cured insulating protective layer encapsulates and protects the connection points between electronic components and the PCB that are higher than 5mm.

6. The PCBA as described in claim 1, characterized in that, The UV-cured insulating protective layer on the PCB has multiple independently spaced encapsulation areas.

7. The PCBA as described in claim 1, characterized in that, The UV-cured insulating protective layer completely encapsulates electronic components with a height of less than 2mm. Alternatively, the UV-cured insulating protective layer can completely encapsulate electronic components with a height of less than 1 mm.

8. The PCBA as described in claim 1, characterized in that, The UV-cured insulating protective layer has an upper surface and a circumferential side edge surface surrounding the upper surface; the circumferential side edge surface is a controllable regular surface.

9. The PCBA as described in claim 8, characterized in that, The height of the circumferential side edge surface is less than 5 mm.

10. The PCBA as described in claim 8, characterized in that, The circumferential side edge surface is perpendicular to the PCB surface when the thickness is above 300 micrometers.

11. The PCBA as described in claim 10, characterized in that, The longitudinal section of the circumferential side edge surface is an oblique line or a vertical line.

12. The PCBA as described in claim 1, characterized in that, The PCBA includes one or more of the following: electric drive circuit board, power supply circuit board, electronic control circuit board, and electromagnetic circuit board.

13. The PCBA as described in claim 12, characterized in that, The voltage, current, or heat generation of the electronic components covered by the UV-cured insulating protective layer and the adjacent PCB area has a greater voltage difference, current difference, or heat generation difference than other areas of the PCB.

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