Paster jumper wire and preparation method thereof, and circuit board assembly

Abstract

The invention discloses a patch jumper wire, a preparation process thereof and a circuit board assembly. The patch jumper wire comprises an arch-bridge-shaped conductive main body and pins horizontally extending from the two ends of the arch-bridge-shaped conductive main body. The surface of the arch-bridge-shaped conductive main body is coated with an epoxy molding compound layer, the bottom of the epoxy molding compound layer is of a plane structure, the surface of the bottom is provided with a microscopic groove structure, and the surfaces of the pins are provided with electroplated layers; the patch jumper wire is reasonable in structural design, has good welding performance and red glue bonding strength, can be compatible with a solder paste mounting process and a red glue mounting process, and is suitable for high-reliability electronic assembly occasions.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of patch jumpers, in particular to a patch jumper, a preparation method thereof and a circuit board assembly. BACKGROUND

[0002] Traditional patch jumpers in electronic assembly are often designed in a single structure, which cannot be compatible with both tin paste welding and red glue mounting processes, resulting in manufacturers needing to develop and store two types of products for different application scenarios, significantly increasing the complexity of supply chain management and production costs. In addition, the existing jumper structure is prone to tin beads and poor welding during reflow soldering, and the adhesion strength between the insulating coating material and the red glue is insufficient, which can easily fall off during subsequent use. Although the existing epoxy molding compound system is widely used in packaging fields, the conventional formula has weak polarity, uneven filler dispersion and poor compatibility with red glue, resulting in low push value after mounting, which is difficult to meet the high reliability requirements. Therefore, there is an urgent need for a new type of patch jumper with optimized structure, material adaptation and strong process compatibility to meet the dual requirements of tin paste welding and red glue mounting, and to improve the overall electrical performance and mechanical stability. SUMMARY

[0003] To solve the above problems, one of the purposes of the present application is to provide a patch jumper, which comprises an arch bridge-shaped conductive main body and pins horizontally extending from both ends of the arch bridge-shaped conductive main body; the surface of the arch bridge-shaped conductive main body is coated with an epoxy molding compound layer, the bottom of the epoxy molding compound layer is a flat structure and the bottom surface is provided with a micro-groove structure, and the surface of the pin is provided with an electroplated layer. The patch jumper provided by the present application has a good weldability electroplated layer pin, which can be well infiltrated with tin paste to form a reliable metallurgical welding point; the horizontally extending pin ensures that the pin is fully attached to the PCB board, and the tin paste can fully fill the gap between the pin and the pad during welding to form a stable electrical connection and mechanical fixation; the arch bridge-shaped conductive main body provides space for the exhaust and flow of tin paste during reflow soldering, reducing the risk of tin bead generation; the flat structure of the bottom of the epoxy molding compound layer can maximize the contact with the PCB board to provide a stable and uniform adhesion substrate for the red glue, and the micro-groove structure can increase the contact area with the red glue to form a mechanical interlock with the red glue, thereby improving the adhesion strength with the red glue and achieving a push force of more than 7N.

[0004] Another purpose of the present application is to provide a preparation method of the patch jumper, comprising the following steps: Preparation of epoxy molding compound particles; Punching: the metal strip is integrally formed into a connected structure by a punching process, the connected structure comprising an arch bridge-shaped conductive main body with a middle part upwardly protruding, and pins horizontally extending from both ends of the arch bridge-shaped conductive main body; Mold injection: the integrated structure is placed in a mold and epoxy molding particles are injected to mold the arch bridge-shaped conductive body, so that the epoxy molding particles melt and uniformly coat the surface of the arch bridge-shaped conductive body to form an epoxy molding layer with a flat structure at the bottom; wherein the inner cavity surface of the mold is provided with a micro convex structure, so that during the mold injection process, the surface of the epoxy molding layer synchronously forms a corresponding micro groove structure; by machining precise micro convexes on the mold, the molten epoxy molding material will fill the gap around the convex during the molding process, thereby directly copying the corresponding groove structure, which can avoid subsequent secondary processing steps such as laser engraving and chemical etching, greatly improving production efficiency and structural consistency.

[0005] Electroplating: electroplating the pins to form an electroplating layer on the surface of the pins; Cutting: the integrated structure treated by the foregoing processes is cut or laser cut along the preset cutting line to separate into individual patch jumpers.

[0006] The present application punches out the integrated structure of the arch bridge-shaped conductive body and the horizontal pin in one step, without subsequent assembly. The arch bridge-shaped conductive body and the pin are made of the same metal substrate, without a welding interface, which can avoid the problem of increased resistance caused by welding and eliminate the mounting error caused by the skew of the pin welding. The method of mold injection followed by electroplating can ensure that the electroplating layer is in the purest and best state, providing the best welding surface for SMT mounting. If electroplating is performed first and then mold injection, the high-temperature and high-pressure mold injection process will damage the delicate electroplating layer on the surface of the pin, causing oxidation, contamination or uneven thickness of the electroplating layer, which will seriously affect subsequent welding.

[0007] Preferably, the process parameters of mold injection are as follows: mold temperature 140-160℃, injection pressure 10-15MPa, and curing time 60-120s. The mold temperature matches the curing reaction temperature range of the epoxy molding material, ensuring that the resin is fully crosslinked. The appropriate injection pressure can extrude the bubbles of the epoxy molding particles when they melt, avoiding voids in the molding layer. The appropriate curing time can ensure that the crosslinking reaction is complete, so that the hardness of the epoxy molding layer meets the requirements.

[0008] Preferably, the preparation of the epoxy molding material includes the following steps: Raw material pretreatment: dry the silicon powder at 115-125℃ for 3.5-4.5h, and preheat the carboxyl-terminated butylnitrile liquid rubber at 55-65℃ for 15-25min to reduce the viscosity for better dispersion; Mixing: 18-20 parts of bisphenol A type epoxy resin, 13-15 parts of o-cresol formaldehyde epoxy resin, 8-10 parts of linear phenolic resin, 1.5-2.5 parts of 2-methyl imidazole and 1.5-2.5 parts of antioxidant are mixed and stirred according to the mass fraction, and heated to 85-95℃, then 7-9 parts of carboxyl-terminated butyl nitrile liquid rubber, 5-7 parts of silane coupling agent, 34-46 parts of silicon powder are continuously stirred for 0.5-1h to obtain mixture a; Melt extrusion and cooling: mixture a is sent into a double screw extruder for melt mixing, then extruded and cooled to obtain a strip; Crushing: the cooled strip is crushed into epoxy molding compound particles.

[0009] The traditional epoxy molding compound is often poor in compatibility with red glue due to insufficient polarity of the resin in the formula and uneven dispersion of the filler, low thrust value after mounting, and easy fracture at the interface between the molding compound and the red glue. The compatibility of the epoxy molding compound with the red glue is greatly improved by improving the formula and the preparation process conditions of the epoxy molding compound. The bisphenol A type epoxy resin contains a large amount of hydroxyl groups, has strong polarity, and has good chemical compatibility with the red glue. The o-cresol formaldehyde epoxy resin contains multiple functional groups, forms a high-density cross-linked structure after curing, and improves the rigidity of the molding compound layer. The carboxyl groups at both ends of the carboxyl-terminated butyl nitrile liquid rubber can react with the epoxy groups of the epoxy resin, dispersing the elastic rubber particles in the cross-linked network of the molding compound. When subjected to a thrust force, the rubber particles can absorb energy and disperse stress, avoiding interface separation.

[0010] Preferably, the silane coupling agent is at least one of KH-550 and KH-560. The silane coupling agent can improve the compatibility of the silicon powder with the epoxy resin, form a bridging structure, and eliminate the interface gap.

[0011] Preferably, the antioxidant is any one of antioxidant 1024, antioxidant 1010 or antioxidant 1076. In a high temperature environment, the resin molecules in the epoxy molding compound are easily oxidized to generate active free radicals to initiate a chain reaction, leading to molecular chain rupture. The antioxidant can combine with active free radicals to terminate the chain reaction, ensuring that the molecular structure of the epoxy molding compound layer is stable during high temperature processing and long-term use, and the compatibility and mechanical strength of the epoxy molding compound layer with the red glue do not decrease.

[0012] Preferably, the temperature of each zone of the double screw extruder is: the temperature of the first zone is 100-110℃, the temperature of the second zone is 120-130℃, the temperature of the third zone is 135-145℃, the temperature of the die is 125-135℃, and the production rate is 200-250Kg / h. The use of gradient heating in the double screw extruder can prevent the decomposition and coking of each component in the formula due to thermal shock, ensure that the resin and the filler are gradually melted and uniformly mixed, and finally ensure that the quality of the epoxy molding compound particles is consistent, and the performance after molding is stable.

[0013] It is another object of the present application to provide a circuit board assembly comprising a printed circuit board and a jumper mounted thereon, wherein the jumper is the patch jumper described above.

[0014] Preferably, the patch jumper is mounted by a solder paste process, wherein the solder paste is disposed between the pin and the pad of the printed circuit board.

[0015] Preferably, the patch jumper is mounted by a red glue process, wherein the red glue is disposed between the epoxy molding compound layer and the printed circuit board.

[0016] The patch jumper provided by the present application has multiple beneficial effects: first, the conductive main body in an arch bridge shape and the horizontal pin are integrally stamped, which can not only avoid the increase in resistance and mounting deviation caused by the traditional welding interface, but also ensure that the pin and the PCB pad are fully attached to improve the welding quality, and the arch bridge structure can also provide an exhaust passage for solder paste reflow to reduce the generation of solder beads; second, the bottom of the epoxy molding compound layer is provided with a micro groove, which can maximize the contact area and significantly improve the adhesion strength with the red glue through mechanical interlocking, so that the thrust is increased to more than 7N; third, the horizontal pin and the epoxy molding compound layer can ensure that the patch jumper is compatible with both solder paste and red glue mounting processes; the jumper has high reliability, strong adhesion and process versatility, effectively reduces inventory and manufacturing costs, and is suitable for various electronic assembly scenarios. BRIEF DESCRIPTION OF DRAWINGS

[0017] The drawings described herein are used to provide further understanding of the present application, and form a part of the present application. The schematic embodiments of the present application and their descriptions are used to explain the present application, and do not constitute an improper limitation on the present application. In the drawings: Figure 1 is a sectional view of the patch jumper of the present application; Figure 2 is a photograph of the patch jumper of the present application; Figure 1 is a photograph of the patch jumper of the present application; 1. an arch bridge-shaped conductive main body; 2. a pin; 3. an epoxy molding compound layer. DETAILED DESCRIPTION

[0018] The present application will be further described in detail below with reference to specific embodiments, so that those skilled in the art can more clearly understand the present application.

[0019] The following examples are used to illustrate the present application, but are not used to limit the scope of the present application. Based on the specific embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0020] In the embodiments of the present application, all raw material components are commercially available products well known to those skilled in the art, unless otherwise specified; in the embodiments of the present application, the technical means used are conventional means well known to those skilled in the art, unless otherwise specified.

[0021] Raw material sources: Bisphenol A type epoxy resin, model CYDW-100, purchased from Shanghai Hongzhuang Chemical Technology Co., Ltd.; O-cresol formaldehyde epoxy resin, model CYDCN-200, purchased from Shandong Yixin New Material Co., Ltd.; Linear phenolic resin, model YHY-8210, purchased from Lvhuan (Jinan) Chemical Technology Co., Ltd.; 2-methylimidazole, purchased from Shandong Guohua Chemical Co., Ltd.; Antioxidants 1024, 1010, 1076, all purchased from Dezhou Huazhen New Material Co., Ltd.; Carboxyl-terminated butylnitrile liquid rubber (CTBN), purchased from Zibo Qilong Chemical Co., Ltd.; Silane coupling agent KH-550, KH-560, both purchased from Shandong Yuanjin New Material Co., Ltd.; Silicon powder, purchased from Shanghai Xiangtian Nanometer Material Co., Ltd.; Red glue is an epoxy red glue, model Loctite Red Glue 3611 and Japan 5011N, purchased from Shenzhen Debang Technology Co., Ltd. and Dongguan Tengchuan Adhesive Products Co., Ltd., respectively; The remaining raw materials are conventional commercially available.

[0022] Example 1 The present embodiment provides a patch jumper, which comprises an arch bridge-shaped conductive body 1 and a pin 2 horizontally extending from both ends of the arch bridge-shaped conductive body 1; the surface of the arch bridge-shaped conductive body 1 is coated with an epoxy molding compound layer 3, the bottom of the epoxy molding compound layer 3 is a plane structure and the bottom surface is provided with a micro groove structure, and the surface of the pin 2 is provided with a plating layer. The preparation method of the above-mentioned patch jumper comprises the following steps: Preparation of epoxy molding compound particles; Punching: the metal strip is integrally formed into a connected structure by a punching process, the connected structure comprising a conductive body with a middle part upwardly protruding in an arch bridge shape, and a pin horizontally extending from both ends of the arch bridge-shaped conductive body; Mold injection: the integrated structure is placed in a mold injection mold, and epoxy molding particles are injected to mold injection of the arch bridge-shaped conductive main body, so that the epoxy molding particles are uniformly coated on the surface of the arch bridge-shaped conductive main body after melting to form an epoxy molding layer with a flat structure at the bottom; wherein the inner cavity surface of the mold is provided with a micro convex structure, so that a micro groove structure corresponding to the surface of the epoxy molding layer is formed synchronously during the mold injection process; wherein the mold injection process parameters are set as a mold temperature of 140℃, an injection pressure of 10MPa, and a curing time of 60s; Electroplating: electroplating the pins to form an electroplated layer on the surface of the pins; Cutting: the integrated structure treated by the foregoing processes is cut or laser cut along the preset cutting line to separate into individual patch jumpers.

[0023] Preparation of the epoxy molding particles includes the following steps: Raw material pretreatment: dry the silicon powder at 115℃ for 3.5h, and preheat the carboxyl-terminated butylnitrile liquid rubber at 55℃ for 15min; Mixing: mix and stir 18 parts of bisphenol A type epoxy resin, 13 parts of o-cresol formaldehyde epoxy resin, 8 parts of linear phenolic resin, 1.5 parts of 2-methyl imidazole, and 1.5 parts of antioxidant, and heat to 85℃, then add 7 parts of carboxyl-terminated butylnitrile liquid rubber, 5 parts of silane coupling agent, and 46 parts of silicon powder, and continue to stir for 0.5h to obtain a mixture a; wherein the silane coupling agent is KH-550; the antioxidant is antioxidant 1024; Melt extrusion and cooling: send the mixture a into a double screw extruder for melt mixing, then extrude and cool to obtain a material strip; wherein the temperature of each zone of the double screw extruder is: the temperature of zone one is 100℃, the temperature of zone two is 120℃, the temperature of zone three is 135℃, the temperature of the die head is 125℃, and the production rate is 200Kg / h; Crushing: crush the cooled material strip into epoxy molding particles.

[0024] The embodiment also provides a circuit board assembly, which includes a printed circuit board and a jumper mounted thereon, the jumper being the patch jumper described above, and the patch jumper being mounted by a tin paste process, and the tin paste being arranged between the pins and the pads of the printed circuit board.

[0025] Example 2 The difference between this embodiment and example 1 is that the mold injection process parameters are set as a mold temperature of 150℃, an injection pressure of 12MPa, and a curing time of 90s; During the preparation of the epoxy molding particles, the silicon powder is dried at 120℃ for 4h, and the carboxyl-terminated butylnitrile liquid rubber is preheated at 60℃ for 20min; Mixing 19 parts of bisphenol A type epoxy resin, 14 parts of o-cresol formaldehyde epoxy resin, 9 parts of linear phenolic resin, 2 parts of 2-methyl imidazole and 2 parts of antioxidant by mass fraction, stir and heat to 90℃, then add 8 parts of carboxyl-terminated butyl nitrile liquid rubber, 6 parts of silane coupling agent, 40 parts of silicon powder and continue to stir for 0.75h to obtain mixture a; wherein the silane coupling agent is selected from KH-560; the antioxidant is antioxidant 1010; the temperature of each zone of the double screw extruder is: the temperature of the first zone is 105℃, the temperature of the second zone is 125℃, the temperature of the third zone is 140℃, the temperature of the die head is 130℃, and the production rate is 225Kg / h; The embodiment also provides a circuit board assembly comprising a printed circuit board and a jumper wire attached thereto, the jumper wire being the patch jumper wire described above, the patch jumper wire being attached by a red glue process, the red glue being arranged between the epoxy molding compound layer and the printed circuit board, the diameter of the needle used for dispensing is 0.4mm, the dispensing pressure is 30N, and the dispensing speed is 10mm / s.

[0026] Example 3 The difference between the embodiment and example 1 is that the mold injection process parameters are set as a mold temperature of 160℃, an injection pressure of 15MPa, and a curing time of 120s. During the preparation of the epoxy molding compound particles, the silicon powder is dried at 125℃ for 4.5h, and the carboxyl-terminated butyl nitrile liquid rubber is preheated at 65℃ for 25min. Mixing 19 parts of bisphenol A type epoxy resin, 14 parts of o-cresol formaldehyde epoxy resin, 9 parts of linear phenolic resin, 2 parts of 2-methyl imidazole and 2 parts of antioxidant by mass fraction, stir and heat to 90℃, then add 8 parts of carboxyl-terminated butyl nitrile liquid rubber, 6 parts of silane coupling agent, 40 parts of silicon powder and continue to stir for 0.75h to obtain mixture a; wherein the silane coupling agent is selected from KH-560; the antioxidant is antioxidant 1010; the temperature of each zone of the double screw extruder is: the temperature of the first zone is 105℃, the temperature of the second zone is 125℃, the temperature of the third zone is 140℃, the temperature of the die head is 130℃, and the production rate is 225Kg / h; The embodiment also provides a circuit board assembly comprising a printed circuit board and a jumper wire attached thereto, the jumper wire being the patch jumper wire described above, the patch jumper wire being attached by a red glue process, the red glue being arranged between the epoxy molding compound layer and the printed circuit board, the diameter of the needle used for dispensing is 0.4mm, the dispensing pressure is 30N, and the dispensing speed is 10mm / s.

[0027] Comparative Example 1 The difference between the comparative example and example 1 is that the jumper wire is prepared by first electroplating the pins and then mold injection, and the remaining process steps are the same as those of example 1.

[0028] Comparative Example 2 The difference between the present comparative example and Example 2 is that, in the preparation of the epoxy molding compound particles, 19 parts of bisphenol A epoxy resin is increased to 33 parts, and no o-cresol formaldehyde epoxy resin is added, and the remaining process steps are the same as those of Example 2.

[0029] Comparative Example 3 The difference between the present comparative example and Example 3 is that, in the preparation of the epoxy molding compound particles, 20 parts of bisphenol A epoxy resin is increased to 30 parts, and no linear phenolic resin is added, and the remaining process steps are the same as those of Example 3.

[0030] Comparative Example 4 The difference between the present comparative example and Example 3 is that the bottom of the epoxy molding compound layer is a flat structure and the bottom surface is not provided with a micro-groove structure, and the remaining process steps are the same as those of Example 3.

[0031] The performance of the patch jumpers prepared in Examples 1-3 and Comparative Examples 1-4 is detected.

[0032] Test method: The red glue bonding strength (thrust test) is tested according to the IPC-TM-650 2.4.22 standard "Adhesion Strength of SMT Adhesives (Shear Test)", a thrust tester is used to push the patch jumper in a direction parallel to the surface of the PCB, and the maximum force value when the bonding part is damaged is recorded; The soldering strength is tested according to the IPC-TM-650 Method 2.4.23 standard, a thrust tester is used to push the patch jumper in a direction parallel to the surface of the PCB, and the maximum force value when the solder joint fails is recorded; The test results are shown in Table 1.

[0033] Table 1 Performance test table of patch jumper

[0034] From the above experimental data, the soldering strength of the patch jumper in Example 1 reaches 13.1 N using the tin paste process, which reflects the excellent performance of the patch jumper under the tin paste soldering, which may be due to the perfect electroplated layer on the pin surface, the full adhesion of the horizontal pin and the PCB pad, and the exhaust space provided by the arch bridge structure for the tin paste reflow; Examples 2 and 3 are both attached using the red glue process, and the red glue bonding strength (thrust value) of the patch jumper reaches more than 7 N, which may be due to the micro-groove structure at the bottom of the epoxy molding compound layer effectively increasing the contact area with the red glue and improving the bonding strength through mechanical interlocking, and the optimized epoxy molding compound formula ensures good compatibility with the red glue.

[0035] Continuing to analyze the data in Table 1, it can be seen that when the patch jumper of Comparative Example 1 is prepared, the step of mold injection is exchanged with the step of electroplating, which results in the welding strength being reduced to 6.3 N. This may be because the electroplating is performed first and then the mold injection is performed, and the high-temperature and high-pressure mold injection process destroys the electroplated layer on the surface of the pin, which causes the electroplated layer to be oxidized, contaminated or uneven in thickness, thereby affecting the reliability and strength of the solder paste welding. The epoxy molding compound particles prepared in Comparative Example 2 are not added with o-cresol formaldehyde epoxy resin, and the epoxy molding compound particles prepared in Comparative Example 3 are not added with linear phenolic resin, which both result in the red glue bonding strength being reduced. This may be because the above components will cause the crosslinking density of the epoxy molding compound layer to be reduced, and the chemical compatibility with the red glue is poor, thereby causing the bonding strength to be reduced. The red glue bonding strength is reduced to 2.5 N when the microgroove structure is not set in Comparative Example 4. This may be because the microgroove structure is lacking, which reduces the contact area with the red glue, and mechanical interlocking cannot be formed, thereby significantly reducing the bonding strength.

[0036] In summary, the patch jumper provided by the present application is compatible with two kinds of mounting processes of solder paste and red glue, has the advantages of high welding strength, strong red glue adhesion, stable structure, strong process adaptability and the like, can be widely applied to circuit board assemblies in the fields of communication equipment, automotive electronics, consumer electronics and the like, and effectively improves the reliability and production efficiency of electronic assembly.

[0037] The above is only an embodiment of the present application and is not used to limit the present application. The present application can have various changes and variations for those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the scope of the claims of the present application.

Claims

1. A patch jumper, characterized in that, The jumper comprises an arch bridge-shaped conductive main body and pins horizontally extended from both ends of the arch bridge-shaped conductive main body; the surface of the arch bridge-shaped conductive main body is coated with an epoxy molding compound layer, the bottom of the epoxy molding compound layer is a plane structure and the bottom surface is provided with a micro-groove structure, and the surface of the pin is provided with a plating layer.

2. A method of making a patch jumper, characterized by, The method comprises the following steps: Preparation of epoxy molding compound particles; Punching: the metal strip is integrally formed into a connected structure by a punching process, the connected structure comprising an arch bridge-shaped conductive main body with a middle part upwardly protruding, and pins horizontally extended from both ends of the arch bridge-shaped conductive main body; Mold injection: the connected structure is placed in a mold injection mold, and the epoxy molding compound particles are injected, the arch bridge-shaped conductive main body is subjected to mold injection, the epoxy molding compound particles are uniformly coated on the surface of the arch bridge-shaped conductive main body to form an epoxy molding compound layer with a plane structure at the bottom; wherein the inner cavity surface of the mold is provided with a micro-convex structure, so that a micro-groove structure corresponding to the surface of the epoxy molding compound layer is formed synchronously during mold injection; Plating: the pins are plated to form a plating layer on the surface of the pins; Cutting: the connected structure treated by the foregoing processes is cut or laser cut along the preset cutting line to separate into individual patch jumpers.

3. The preparation method according to claim 2, characterized in that, The process parameters of the mold injection are as follows: mold temperature 140-160℃, injection pressure 10-15MPa, and curing time 60-120s.

4. The production method according to claim 2, characterized by, The preparation of the epoxy molding compound particles comprises the following steps: Raw material pretreatment: dry the silicon powder at 115-125℃ for 3.5-4.5h, and preheat the carboxyl-terminated butylnitrile liquid rubber at 55-65℃ for 15-25min; Mixing: mix and stir 18-20 parts of bisphenol A type epoxy resin, 13-15 parts of o-cresol formaldehyde epoxy resin, 8-10 parts of linear phenolic resin, 1.5-2.5 parts of 2-methyl imidazole, and 1.5-2.5 parts of antioxidant, and heat to 85-95℃, then add 7-9 parts of carboxyl-terminated butylnitrile liquid rubber, 5-7 parts of silane coupling agent, and 34-46 parts of silicon powder, and continue to stir for 0.5-1h to obtain a mixture a; Melt extrusion and cooling: send the mixture a into a double screw extruder for melt mixing, then extrude and cool to obtain a material strip; Crushing: crush the cooled material strip into epoxy molding compound particles.

5. The preparation method according to claim 4, characterized in that, The silane coupling agent is at least one of KH-550 and KH-560.

6. The preparation method according to claim 4, characterized in that, The antioxidant is any one of antioxidant 1024, antioxidant 1010 or antioxidant 1076.

7. The preparation method according to claim 4, characterized in that, The temperature of each zone of the double screw extruder is as follows: the temperature of the first zone is 100-110℃, the temperature of the second zone is 120-130℃, the temperature of the third zone is 135-145℃, the temperature of the die head is 125-135℃, and the production rate is 200-250Kg / h.

8. A circuit board assembly comprising a printed circuit board and a jumper attached thereto, characterized in that, The jumper is the patch jumper of claim 1.

9. The circuit board assembly of claim 8, wherein, The patch jumper is attached by a tin paste process; wherein the tin paste is arranged between the pin and the pad of the printed circuit board.

10. The circuit board assembly of claim 8, wherein, The patch jumper is attached by a red glue process; wherein the red glue is arranged between the epoxy molding compound layer and the printed circuit board.

Images