Printed circuit board integrated with magnetic inductor and manufacturing method thereof

Abstract

The invention discloses a printed circuit board integrated with a magnetic inductor and a manufacturing method thereof, the printed circuit board comprises a substrate, a magnetic core and an inductance winding, the substrate is provided with a cavity, the magnetic core is embedded in the cavity and is provided with a plurality of through holes, the inductance winding comprises copper columns, the number of the copper columns corresponds to that of the through holes, and the copper columns are embedded in the cavity. Each copper column penetrates through one through hole, the two ends of each copper column are provided with a first circuit layer and a second circuit layer respectively, the first circuit layer of each copper column is connected with the first circuit layer of one adjacent copper column through inductance copper, and the second circuit layer of each copper column is connected with the second circuit layer of the other adjacent copper column through inductance copper. According to the printed circuit board integrated with the magnetic inductor and the manufacturing method of the printed circuit board, the magnetic core and the printed circuit board are manufactured at the same time and assembled in a combined mode, the surface area of the printed circuit board is saved, and the printed circuit board is more integrated; and the method of pre-embedding the copper columns is adopted, so that the overall direct-current resistance value of the device is effectively reduced, and the inductance efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of electronic manufacturing, and in particular to a printed circuit board with integrated magnetic inductor and a manufacturing method thereof. Background Art

[0002] With the rapid development of electronic devices such as mobile devices and wearable devices towards miniaturization, high performance and multi-functional module integration, the integration and performance requirements of printed circuit boards (PCBs) are increasing.

[0003] Inductors play a vital role in circuits, including energy storage, filtering, impedance matching, signal coupling, and electromagnetic interference suppression. They are widely used in power management, communications, signal processing, and other fields, and are indispensable components in electronic devices. However, traditional discrete inductors are large in size, which seriously hinders the further miniaturization and high integration of PCBs.

[0004] Therefore, integrated inductor technology came into being and has developed rapidly. Integrated inductor technology shows many advantages by directly building inductor components on PCB: shortening the signal transmission path reduces signal loss during transmission and reduces the impact of parasitic parameters on circuit performance; reducing welding points and external lead connections, which can significantly improve product reliability and durability, and reduce the risk of failure caused by poor welding or loose external connections; reducing the number of discrete inductor components and welding points, thereby reducing the generation of electronic waste and helping to achieve green and sustainable development. In summary, integrated inductor technology has important application value and broad development prospects.

[0005] At present, PCB integrated inductor technology mainly embeds a ring-shaped magnetic core in the substrate, and then sets vias and windings around the magnetic core to construct an inductor with a winding-wrapped magnetic core structure. However, the copper thickness of the via hole wall in this structure is limited, resulting in low efficiency of the inductor in the power module. In addition, the winding manufacturing process of this structure is complex, and the process control accuracy is high. In addition, the inductance value accuracy of the manufactured inductor device is poor, and it cannot be applied to actual products at present. Summary of the invention

[0006] The main purpose of the present invention is to provide a printed circuit board with integrated magnetic inductor and a manufacturing method thereof, so as to solve the problem of poor effect of using integrated inductor technology on printed circuit boards in the prior art.

[0007] To achieve the above object, at least one embodiment of the present invention provides the following technical solution: a printed circuit board with an integrated magnetic inductor, the printed circuit board comprising: Substrate, magnetic core and inductor winding, among which, The substrate is provided with a cavity, the magnetic core is embedded in the cavity and is provided with a plurality of through holes, the inductor winding includes copper pillars corresponding to the number of through holes, each copper pillar passes through a through hole and two ends thereof are respectively provided with a first circuit layer and a second circuit layer, the first circuit layer of each copper pillar is connected to the first circuit layer of an adjacent copper pillar through inductor copper, and the second circuit layer of each copper pillar is connected to the second circuit layer of another adjacent copper pillar through inductor copper.

[0008] For example, in the printed circuit board provided in at least one embodiment of the present application, a plurality of through holes are arranged on the magnetic core in a plurality of parallel rows, and the number of through holes in each row is at least two.

[0009] For example, in the printed circuit board provided in at least one embodiment of the present application, the magnetic core is configured as a semi-cured composite resin magnetic film after heat-pressing and curing, and the semi-cured composite resin magnetic film includes resin and magnetic particles, and the magnetic particles are dispersed in the resin.

[0010] For example, in the printed circuit board provided in at least one embodiment of the present application, the mass fraction of the magnetic particles of the magnetic core is in a range of 20% to 80%.

[0011] For example, in the printed circuit board provided in at least one embodiment of the present application, the average particle size of the magnetic particles of the magnetic core is in the range of 0.1 μm to 20 μm.

[0012] For example, in the printed circuit board provided in at least one embodiment of the present application, the magnetic particles of the magnetic core are at least one of ferrite particles, magnetic metal particles, and magnetic alloy particles.

[0013] For example, in the printed circuit board provided in at least one embodiment of the present application, an insulating layer is formed on the surface of the magnetic particles of the magnetic core.

[0014] On the other hand, at least one embodiment of the present application further provides a method for manufacturing a printed circuit board with an integrated magnetic inductor, the method comprising: Take the base plate and mill out the cavity; Drilling a through hole in the semi-cured composite resin magnetic film, and cutting according to the cavity contour to obtain a semi-cured magnetic core; Placing the copper pillar in the through hole of the semi-cured magnetic core, assembling the semi-cured magnetic core in the cavity, and performing heat pressing after stacking to obtain a circuit board substrate; According to the circuit board substrate, an inductor winding is formed on the circuit board substrate to obtain the printed circuit board.

[0015] For example, in the method for manufacturing a printed circuit board provided in at least one embodiment of the present application, the step of forming an inductor winding on the circuit board substrate according to the circuit board substrate to obtain the printed circuit board includes: Removing residual glue from the surface of each copper column and the circuit board substrate, so that all copper columns are exposed on the upper and lower surfaces and maintain a consistent height; The printed circuit board is obtained by etching the inductor copper and connecting the adjacent copper pillars on the upper surface and the lower surface of the circuit board substrate to form an inductor winding on the circuit board substrate.

[0016] For example, in the method for manufacturing a printed circuit board provided in at least one embodiment of the present application, after forming an inductor winding on the circuit board substrate according to the circuit board substrate to obtain the printed circuit board, the method further includes: An inductance online monitoring device is used to connect with the inductance winding of the printed circuit board and to modify the inductance value online.

[0017] Compared with the prior art, any embodiment of the present invention has at least the following beneficial effects: The present invention provides a multilayer printed circuit board with integrated inductance, comprising: a substrate, a magnetic core and an inductor winding, wherein the substrate is provided with a cavity, the magnetic core is embedded in the cavity and provided with a plurality of through holes, the inductor winding comprises copper pillars corresponding to the number of through holes, each copper pillar passes through a through hole and the two ends are respectively provided with a first circuit layer and a second circuit layer, the first circuit layer of each copper pillar is connected to the first circuit layer of an adjacent copper pillar through inductor copper, and the second circuit layer of each copper pillar is connected to the second circuit layer of another adjacent copper pillar through inductor copper. In the printed circuit board of the present application, the upper and lower layers of the inductor device are connected by pre-embedded copper pillars to form an inductor winding, which can effectively reduce the overall DC resistance value of the device, thereby having a higher inductor efficiency in actual use. On the other hand, through the combined assembly method of the substrate and the magnetic core, the processing technology can be flexibly adjusted, no additional processing steps are required, and the surface area of ​​the printed circuit board is saved, making the printed circuit board more miniaturized and planar. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic structural diagram of a printed circuit board integrated magnetic core inductor according to an embodiment of the present application; Figure 2 is a schematic structural diagram of a substrate according to an embodiment of the present application; Figure 3 is a schematic structural diagram of a magnetic core according to an embodiment of the present application; Figure 4 is a schematic structural diagram of an inductor winding according to an embodiment of the present application; Figure 5 is a schematic structural diagram of a printed circuit board integrated magnetic core inductor according to another embodiment of the present application; Figure 6 It is a schematic cross-sectional structure diagram of a printed circuit board integrated magnetic core inductor according to an embodiment of the present application; Figure 7 It is a structural schematic diagram of a printed circuit board integrated magnetic core inductor according to another embodiment of the present application.

[0019] Description of the drawings: 10, substrate; 101, cavity; 20, magnetic core; 201, through hole; 202, semi-cured composite resin magnetic film; 30, inductor winding; 301, copper column; 302, first circuit layer; 303, second circuit layer.

[0020] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0022] The terms "first", "second" and "third" in this application are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus, the features defined as "first", "second" and "third" can explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. All directional indications (such as up, down, left, right, front, back...) in the embodiments of this application are only used to explain the relative position relationship, movement, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication also changes accordingly. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally also includes steps or units that are not listed, or optionally also includes other steps or units inherent to these processes, methods, products or devices.

[0023] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0024] The current PCB (printed circuit board) integrated inductor technology mainly adopts the method of pre-embedding the ring core material inside the PCB substrate, and then setting the via holes around the core and forming the winding through these via holes, so as to form a structure in which the winding wraps the core. However, there are several key problems with this structure: First, due to the limitations of the PCB manufacturing process, the thickness of the copper layer on the via hole wall is limited. This leads to a high DC resistance (DCR) of the winding, which is not the ideal low DC resistance. The higher DC resistance will increase the energy loss of the inductor component during operation, thereby reducing the overall efficiency, especially in high-frequency switching power supply modules. Second, the process of building the winding involves a complex manufacturing process, which not only increases the production cost, but also places very high precision requirements on process control. Minor deviations may lead to unevenness between windings, which in turn affects the performance of the final inductor. Third, due to the limitations of the manufacturing process, the inductance value (inductance) of the inductor devices currently manufactured often has a large tolerance range. This means that there may be significant performance differences between inductors of the same model, and it cannot meet the needs of applications that have strict requirements on inductance.

[0025] Based on the above problems, this application provides the following technical solutions to improve and optimize the application of integrated inductor technology in PCB manufacturing. Figure 1 to Figure 7 : is a schematic diagram of the structure of each embodiment of the printed circuit board with integrated magnetic inductor provided by the present application. In at least one embodiment, see Figure 1 The printed circuit board of the integrated magnetic inductor includes: a substrate 10, a magnetic core 20 and an inductor winding 30, which are assembled in a matching manner.

[0026] See also Figure 2~Figure 6 The substrate 10 is provided with a cavity 101, the magnetic core 20 can be embedded in the cavity 101, and a plurality of through holes 201 are opened. The inductor winding 30 includes copper pillars 301 corresponding to the number of through holes 201. Each copper pillar 301 passes through a through hole 201 and has two ends respectively configured as a first circuit layer 302 and a second circuit layer 303. The first circuit layer 302 of each copper pillar 301 is connected to the first circuit layer 302 of an adjacent copper pillar 301 through inductor copper, and the second circuit layer 303 of each copper pillar 301 is connected to the second circuit layer 303 of another adjacent copper pillar 301 through inductor copper.

[0027] In this embodiment, the printed circuit board can be made into a rigid circuit board, a flexible circuit board, and a rigid-flexible circuit board, which is not limited in the embodiments of the present application.

[0028] Specifically, the number of windings formed by the inductor copper of the inductor winding 30 of the printed circuit board can be one or more, which is set according to the actual application requirements. It can be understood that each inductor winding 30 can be, but is not limited to, a part of a turn of the inductor winding 30, such as half a turn, or a complete turn, two turns, three turns, etc. The more turns the inductor winding 30 has, the greater the inductance is when other conditions remain unchanged. Therefore, the number of turns of the inductor winding 30 can be designed according to the application scenario, the inductance to be achieved, etc., and the embodiments of the present application do not specifically limit this.

[0029] In some embodiments, the substrate 10 can be made of epoxy resin, polyimide, polyphenylene ether, polytetrafluoroethylene, etc. Understandably, according to the physical and chemical properties of different materials and the environment in which the circuit board is used, selecting a suitable resin material can improve the performance of the circuit board integrated inductor.

[0030] The magnetic core 20 in this embodiment refers to a semi-cured composite resin magnetic film 202 that has been cured by heat pressing. The magnetic core 20 is disposed inside the cavity 101 of the substrate 10; at the same time, a plurality of through holes 201 are disposed inside the magnetic core 20 for accommodating the copper pillars 301; in addition, the upper surface of the magnetic core 20 is flush with the upper surface of the substrate 10, and the lower surface of the magnetic core 20 is flush with the lower surface of the substrate 10, so that the printed circuit board maintains a planar effect.

[0031] Specifically, the semi-cured composite resin magnetic film 202 includes resin, magnetic particles, solvent, curing agent, etc., and the magnetic particles are dispersed in the resin. The semi-cured composite resin magnetic film 202 can improve the inductance value of the integrated inductor of the printed circuit board and improve its energy storage capacity. The semi-cured composite resin magnetic film 202 is formed by uniformly dispersing magnetic particles in a resin solution formed by mixing resin, solvent and curing agent to form a magnetic slurry, coating it into a uniform film layer and gelling it. The finished product of the semi-cured composite resin magnetic film 202 after hot pressing and curing is the magnetic core 20.

[0032] Optionally, the mass fraction of magnetic particles in the magnetic core 20 ranges from 20% to 80%. When the mass fraction of magnetic particles in the magnetic core 20 is less than 20%, the performance improvement effect of the magnetic core 20 on the integrated inductor is less obvious, and the manufacturing cost will be increased; when the mass fraction of magnetic particles in the magnetic core 20 is greater than 80%, the adhesion between the magnetic core 20 and the substrate and the copper pillar 301 will be reduced, affecting the mechanical stability of the integrated inductor.

[0033] Optionally, the average particle size D of the magnetic particles of the semi-cured composite resin magnetic film 202 ranges from 0.1 μm to 20 μm; when the average particle size of the magnetic particles is less than 0.1 μm, the manufacturing difficulty and manufacturing cost of the magnetic particles will increase, and the cost of the magnetic core 20 will increase. When the average particle size of the magnetic particles is greater than 20 μm, short circuits may occur between circuits with smaller spacing.

[0034] In some embodiments, the magnetic particles are selected from at least one of ferrite particles, magnetic metal particles, and magnetic alloy particles.

[0035] In particular, the magnetic particles may be soft magnetic particles, which have high magnetic permeability, low remanence, low coercive force, low magnetic resistance, small hysteresis loss and are easy to be magnetized.

[0036] In the above embodiment, among the materials selected for the magnetic particles, ferrite particles have better electrical insulation and lower loss, and magnetic metal particles or magnetic alloy particles have higher magnetic permeability and magnetic saturation induction intensity. Therefore, when the magnetic gel layer is required to have better electrical insulation and lower loss, ferrite particles can be selected as magnetic particles; when the magnetic gel layer is required to have higher magnetic permeability and magnetic saturation induction intensity, magnetic metal particles or magnetic alloy particles can be selected as magnetic particles.

[0037] Optionally, the ferrite particles include at least one of MnZn ferrite, NiZn ferrite, and the like.

[0038] Optionally, the magnetic metal particles include at least one of iron, cobalt, nickel and the like.

[0039] Optionally, the magnetic alloy particles include at least one of an iron-based crystalline alloy, an iron-based amorphous alloy, a cobalt-based amorphous alloy, and the like.

[0040] Further, the iron-based crystalline alloy includes at least one of FeNi alloy, FeCo alloy, FeAl alloy, FeSiAl alloy, FeNiMo alloy, FeC alloy and the like.

[0041] Further, the iron-based amorphous alloy includes at least one of FeSiB alloy, FeB alloy, FeNiPB alloy, FeNiMoB alloy and the like.

[0042] Further, the cobalt-based amorphous alloy includes at least one of CoFeSiB alloy, CoFeCrSiB alloy, CoNiFeSiB alloy and the like.

[0043] Among the various magnetic alloy particles listed above, compared with iron-based crystalline alloys and iron-based amorphous alloys, cobalt-based amorphous alloys have higher magnetic permeability. Therefore, when the magnetic glue layer requires a higher magnetic permeability, the magnetic particles can use at least one of the cobalt-based amorphous alloys. Compared with cobalt-based amorphous alloys, iron-based crystalline alloys and iron-based amorphous alloys have higher saturation magnetic properties. When the magnetic glue layer requires higher saturation magnetic properties, the magnetic particles can use at least one of iron-based crystalline alloys and iron-based amorphous alloys. Compared with iron-based crystalline alloys, iron-based amorphous alloys and cobalt-based amorphous alloys have lower coercivity. When the magnetic glue layer requires a lower coercivity, the magnetic particles can use iron-based amorphous alloys and cobalt-based amorphous alloys.

[0044] In some embodiments, the surface of the magnetic particles has an insulating layer, which can block direct contact between the magnetic particles, thereby increasing the resistivity of the magnetic core 20 and improving its eddy current loss, thereby improving the performance of the integrated inductor of the circuit board.

[0045] For example, a layer of silicon dioxide may be coated on the surface of the magnetic particles to form an insulating layer.

[0046] For another example, the magnetic particles may be passivated with phosphoric acid to form a non-conductive passivation layer on the surface of the magnetic particles.

[0047] Alternatively, a layer of resin can be adsorbed on the surface of the magnetic particles to increase their insulating properties.

[0048] In some embodiments, the plurality of through holes 201 of the printed circuit board of the present application may also be arranged on the magnetic core 20 in a plurality of parallel rows, with each row containing at least two through holes 201 .

[0049] See also Figure 7 , is another implementation form of the printed circuit board with integrated magnetic inductor, in which multiple groups of through holes 201 are arranged side by side, and the number of through holes 201 in each row is 4. By winding the inductor coil, a Figure 1 or Figure 5 The inductor element has better performance and stronger energy storage capacity. This structural form can be adjusted according to actual needs, and the specific number of the through holes 201 in the embodiment of the present application is not limited.

[0050] In the printed circuit board provided in the above embodiment, the upper and lower layers of the inductor device are connected by pre-embedded copper pillars to form an inductor winding, which can effectively reduce the overall DC resistance of the device, thereby having a higher inductor efficiency in actual use; at the same time, since the inductor winding is realized by the copper pillar passing through the through hole in the magnetic core, it helps to reduce the parasitic capacitance between the inductor and other parts of the PCB. By embedding the magnetic core into the cavity in the substrate, the processing technology can be flexibly adjusted without the need for additional processing steps and the surface area of ​​the printed circuit board can be saved, making the printed circuit board more miniaturized and planarized; it can also increase the stability and durability of the structure, especially when subjected to external shock or vibration. This also helps to maintain the stability of the electrical characteristics of the inductor under various environmental conditions.

[0051] In addition, it is possible to optimize the magnetic field distribution and reduce the interference to the surrounding circuits by properly arranging the positions of copper pillars and vias.

[0052] On the other hand, at least one embodiment of the present application further provides a method for manufacturing a printed circuit board with an integrated magnetic inductor, which is used to manufacture the printed circuit board as described above, and the manufacturing method comprises: A cavity is milled out of a substrate; a through hole is drilled out of a semi-cured composite resin magnetic film, and a semi-cured magnetic core is obtained by cutting according to the contour of the cavity; a copper column is placed in the through hole of the semi-cured magnetic core, the semi-cured magnetic core is assembled in the cavity, and the semi-cured magnetic core is laminated and hot pressed to obtain a circuit board substrate; an inductor winding is formed on the circuit board substrate according to the circuit board substrate to obtain the printed circuit board.

[0053] In some embodiments, mechanical drilling or laser drilling is used to form the cavity and the through hole; for example, laser cutting can be used to form the cavity and the through hole as needed.

[0054] In some embodiments, the size of the semi-cured magnetic core is equal to or slightly smaller than the cavity size, and the copper column diameter is equal to or slightly smaller than the through-hole diameter; preferably, when the size of the semi-cured magnetic core is equal to the cavity size and the copper column diameter is equal to the through-hole diameter, it has a higher matching property, can enhance the mechanical strength, and improve the product stability.

[0055] It should be noted that in the printed circuit board manufacturing method provided in the above embodiment, those skilled in the art can understand and achieve the purpose of the scheme according to the common knowledge of the conventional processing technology of the existing PCB board, for example, the pattern processing, etching steps, etc. that may be required. On the other hand, since the printed circuit board of the present application is realized by assembly, the components such as the substrate, the magnetic core and the copper pillar can be pre-processed at the same time, and the respective order is not limited by the demonstration of the embodiment.

[0056] Furthermore, the above-mentioned method of forming an inductor winding on the circuit board substrate through inductor copper to obtain the printed circuit board includes: removing residual glue on the surface of each copper column and the circuit board substrate to expose the upper surface and the lower surface of all copper columns and maintain a consistent height; etching the inductor copper to connect the adjacent copper columns on the upper surface and the lower surface of the circuit board substrate to form an inductor winding on the circuit board substrate to obtain the printed circuit board.

[0057] In some embodiments, in order to grind away the residual glue on the copper pillars and the surface of the resin substrate, expose all the copper pillars on the upper and lower surfaces, and keep the substrate surface flat and the copper pillars at the same height; mechanical grinding can be used to achieve this, and the specific steps may include but are not limited to: mechanical coarse grinding, mechanical fine grinding, and surface polishing.

[0058] In some embodiments, after the printed circuit board is obtained according to the circuit board substrate, the method further includes: using an inductance online monitoring device to connect to the inductance winding of the printed circuit board and modify the inductance value online. In order to achieve online modification of the inductance value, the inductance online monitoring device is connected to the inductance winding to monitor the inductance value in real time, and then the redundant magnetic core is removed by laser modification to achieve the target inductance value, so that the manufactured inductance has higher precision; the inductance online monitoring device is mainly composed of an inductance measuring device, a test bench and a test cable, and the inductance measuring device can be an impedance analyzer, a vector network analyzer and an LCR meter, etc.

[0059] More completely, after obtaining the printed circuit board, conventional solder mask, text printing, chemical nickel-gold plating, molding, finished product testing and other corresponding process operations can also be carried out.

[0060] The specific implementation methods of the invention are described in detail above, but they are only examples, and the invention is not limited to the specific implementation methods described above. For those skilled in the art, any equivalent modification or substitution of the invention is also within the scope of the invention, therefore, the equalization, modification, improvement, etc. made without departing from the spirit and principle of the invention should be included in the scope of the invention.

Claims

1. A printed circuit board with an integrated magnetic inductor, It is characterized in that The printed circuit board comprises: Substrate, magnetic core and inductor winding, among which, The substrate is provided with a cavity, the magnetic core is embedded in the cavity and is provided with a plurality of through holes, the inductor winding includes copper pillars corresponding to the number of through holes, each copper pillar passes through a through hole and two ends thereof are respectively provided with a first circuit layer and a second circuit layer, the first circuit layer of each copper pillar is connected to the first circuit layer of an adjacent copper pillar through inductor copper, and the second circuit layer of each copper pillar is connected to the second circuit layer of another adjacent copper pillar through inductor copper.

2. The printed circuit board according to claim 1, It is characterized in that A plurality of through holes are arranged in a plurality of parallel rows on the magnetic core, and the number of through holes in each row is at least two.

3. The printed circuit board according to claim 1, It is characterized in that The magnetic core is configured as a semi-cured composite resin magnetic film cured by heat pressing, wherein the semi-cured composite resin magnetic film includes a resin and magnetic particles, wherein the magnetic particles are dispersed in the resin.

4. The printed circuit board according to claim 3, It is characterized in that The mass fraction of magnetic particles in the magnetic core ranges from 20% to 80%.

5. The printed circuit board according to claim 3, It is characterized in that The average particle size of the magnetic particles of the magnetic core is in the range of 0.1 μm to 20 μm.

6. The printed circuit board according to claim 3, It is characterized in that The magnetic particles of the magnetic core are at least one of ferrite particles, magnetic metal particles and magnetic alloy particles.

7. The printed circuit board according to claim 3, It is characterized in that An insulating layer is formed on the surface of the magnetic particles of the magnetic core.

8. A method for manufacturing a printed circuit board with an integrated magnetic inductor, It is characterized in that The printed circuit board manufacturing method comprises: Take the base plate and mill out the cavity; Drilling a through hole in the semi-cured composite resin magnetic film, and cutting according to the cavity contour to obtain a semi-cured magnetic core; Placing the copper pillar in the through hole of the semi-cured magnetic core, assembling the semi-cured magnetic core in the cavity, and performing heat pressing after stacking to obtain a circuit board substrate; According to the circuit board substrate, an inductor winding is formed on the circuit board substrate to obtain the printed circuit board.

9. The method for manufacturing a printed circuit board according to claim 8, It is characterized in that The method of forming an inductor winding on the circuit board substrate to obtain the printed circuit board comprises: Removing residual glue from the surface of each copper column and the circuit board substrate, so that all copper columns are exposed on the upper and lower surfaces and maintain a consistent height; The printed circuit board is obtained by etching the inductor copper and connecting the adjacent copper pillars on the upper surface and the lower surface of the circuit board substrate to form an inductor winding on the circuit board substrate.

10. The method for manufacturing a printed circuit board according to claim 8, It is characterized in that After forming an inductor winding on the circuit board substrate according to the circuit board substrate to obtain the printed circuit board, the method further includes: An inductance online monitoring device is used to connect with the inductance winding of the printed circuit board and to modify the inductance value online.

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