Planar transformer

Abstract

The utility model provides a planar transformer. The planar transformer comprises a PCB winding and two magnetic cores. Each magnetic core comprises a magnetic cover, and a transformer magnetic column, an inductance magnetic column and a side column which are arranged on the magnetic cover; the PCB winding is wound on the transformer magnetic column and the inductance magnetic column; the transformer magnetic columns, the inductance magnetic columns and the side columns of the two magnetic cores are oppositely arranged; and the magnetic cover and the side column surround the transformer magnetic column, the inductance magnetic column and the PCB winding. The problems of high height and electromagnetic compatibility of the magnetic integrated device are solved, the height of the magnetic integrated device is reduced, leakage magnetic flux is shielded, and the effect of optimizing electromagnetic compatibility is achieved.

Description

Technical Field

[0001] The present application belongs to the technical field of planar transformers, and in particular relates to a planar transformer. Background Art

[0002] The current development trend for devices such as microinverters and DC-DC optimizers is modularization: small size, high power density, and high efficiency. Magnetic components, such as transformers and inductors, play a core role in these devices. Advances in magnetic integration technology have enabled the integration of transformers and inductors. However, these integrated magnetic devices also face new challenges: as operating frequencies continue to increase, they may face electromagnetic compatibility (EMC) violations. Furthermore, the height of the device is limited by the height of the integrated magnetic components, hindering further miniaturization. Utility Model Content

[0003] The embodiment of the present application provides a planar transformer to solve the problems of high height and electromagnetic compatibility of magnetic integrated devices, reduce the height of the magnetic integrated devices, shield leakage magnetic flux, and achieve the effect of optimizing electromagnetic compatibility.

[0004] In a first aspect, the present application provides a planar transformer comprising: a PCB winding and two magnetic cores; each magnetic core comprises a magnetic cover and a transformer magnetic column, an inductor magnetic column and a side column arranged on the magnetic cover; the PCB winding is wound on the transformer magnetic column and the inductor magnetic column; the transformer magnetic column, the inductor magnetic column and the side columns of the two magnetic cores are arranged relative to each other; the magnetic cover and the side columns surround the transformer magnetic column, the inductor magnetic column and the PCB winding.

[0005] In one possible implementation, the side column includes a lead opening, the PCB winding includes a coil wound on the transformer magnetic column and the inductor magnetic column and a lead passing through the lead opening, and the magnetic cover and the side column completely surround all parts of the PCB winding except the lead.

[0006] In one possible implementation, the PCB winding includes a primary winding and a secondary winding, and the PCB winding is wound on the transformer magnetic column and the inductor magnetic column, including: the primary winding is wound on the transformer magnetic column, and the secondary winding is wound on the transformer magnetic column and the inductor magnetic column.

[0007] In one possible implementation, the side column includes a first lead and a second lead, the primary winding includes a coil wound on the transformer magnetic column and a first lead passing through the first lead, and the secondary winding includes a coil wound on the transformer magnetic column and the inductor magnetic column and a second lead passing through the second lead; the magnetic cover and the side column completely surround all parts of the PCB winding except the first lead and the second lead.

[0008] In one possible implementation, the height of the lead opening is expressed in millimeters, and the height of the lead opening ranges from 4 mm to 8 mm.

[0009] In one possible implementation, the transformer magnetic column and the inductor magnetic column are arranged in parallel on the magnetic cover.

[0010] In one possible implementation, the side column includes a first side column and a second side column; one end of the first side column and one end of the second side column form a first lead-in; the other end of the first side column and the other end of the second side column form a second lead-in.

[0011] In one possible implementation, the transformer magnetic column includes a first side wall, a second side wall, a third side wall and a fourth side wall; the inductor magnetic column includes a first sub-side wall, a second sub-side wall, a third sub-side wall and a fourth sub-side wall, and a first space is formed between the first side wall and the first sub-side wall; the side column includes a first side column and a second side column; the first side column includes a first side, a second side and a third side, and a second space is formed between the first side and the second side wall, the second sub-side wall, the first part of the third side wall and the first part of the third sub-side wall; the second side column includes a first sub-side, a second sub-side and a third sub-side, and a third space is formed between the first sub-side and the fourth side wall, the fourth sub-side wall, the second part of the third side wall and the second part of the third sub-side wall; the first space, the second space and the third space are used to accommodate the coil of the PCB winding; the side column includes a first lead and a second lead; the first lead is formed between the second side and the second sub-side, and the second lead is formed between the third side and the third sub-side.

[0012] In one possible implementation, the first lead is opposite to the third portion of the third sidewall, and the second lead is opposite to the third portion of the third sub-sidewall.

[0013] In one possible implementation, the magnetic cover, the transformer magnetic column, the inductor magnetic column, and the side columns are integrally formed; or, the transformer magnetic column, the inductor magnetic column, and the side columns are bonded to the magnetic cover.

[0014] The planar transformer provided by the embodiments of the present application includes but is not limited to the following technical effects:

[0015] The planar transformer integrates the transformer and the inductor by arranging the transformer magnetic column and the inductor magnetic column on the magnetic cover, and the PCB winding is wound on the transformer magnetic column and the inductor magnetic column. The winding of the planar transformer adopts PCB winding to achieve the purpose of reducing the height and volume of the planar transformer. Based on the planar design of the PCB winding, the magnetic core can also use an extremely small window height design, and the use of the PCB winding design has better heat dissipation, which can increase the winding current density, increase the power density of the integrated magnetic component, greatly reduce the height dimension, reduce the overall volume, and reduce the total loss under high-frequency applications, so that the planar transformer meets the requirements of modular design. Furthermore, the transformer magnetic column, the inductor magnetic column and the PCB winding are surrounded by the magnetic cover and the side columns, that is, the magnetic core surrounds the PCB winding, so as to achieve the purpose of optimizing EMC. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic diagram of the three-dimensional structure of a planar transformer provided in an embodiment of the present application.

[0017] Figure 2 This is a schematic diagram of a planar transformer decomposition provided in an embodiment of the present application.

[0018] Figure 3 This is a schematic diagram of the positional relationship between a PCB winding and a first magnetic core provided in an embodiment of the present application.

[0019] Figure 4 This is a side view of a planar transformer provided in an embodiment of the present application.

[0020] Figure 5 This is a top view of a planar transformer provided in an embodiment of the present application.

[0021] Figure 6 Schematic diagram of the structure of the magnetic core provided in the embodiment of the present application.

[0022] Description of main component symbols

[0023] 100, planar transformer; 10, PCB winding; 20, first magnetic core; 30, second magnetic core; 21, first magnetic cover; 22, transformer column; 23, inductor column; 24, first side column; 31, second magnetic cover; 32, second side column; 40, lead opening; 241, first side column; 242, second side column; 41, first lead opening; 42, second lead opening; 101, primary winding; 102, secondary winding; 11, coil; 111, coil; 112, coil; 12, lead; 121, first A lead; 122, a second lead; 221, a first side wall; 222, a second side wall; 223, a third side wall; 224, a fourth side wall; 231, a first sub-side wall; 232, a second sub-side wall; 233, a third sub-side wall; 234, a fourth sub-side wall; 51, a first space; 2411, a first side edge; 2412, a second side edge; 2413, a third side edge; 52, a second space; 2421, a first sub-side edge; 2422, a second sub-side edge; 2423, a third sub-side edge; 53, a third space. DETAILED DESCRIPTION

[0024] It should be noted that the terms "first" and "second" in the specification, claims and drawings of this application are used to distinguish similar objects, rather than to describe a specific order or sequence. In the specification, claims and drawings of this application, unless otherwise specified, " / " means or, for example, A / B can mean A or B. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, the term "multiple" in the specification, claims and drawings of this application refers to two or more units.

[0025] It is understood that the connection relationships described in this application refer to direct or indirect connections. For example, A and B are connected or A is electrically connected to B. This can mean that A and B are directly connected, or that A and B are indirectly connected through one or more other electrical components. For example, A and C can be directly connected, and C can be directly connected to B, so that A and B are connected through C.

[0026] The following will describe some embodiments with reference to the accompanying drawings. In the absence of conflict, the following embodiments and features therein may be combined with each other.

[0027] With the development trend of equipment modularization, existing technologies for the application of transformers and inductors in power electronic equipment (such as microinverters and DC-DC optimizers) mainly have the following implementation schemes and their corresponding limitations:

[0028] Independent magnetics: This approach uses a separate transformer and inductor to achieve the required functionality. While this approach is intuitive, its significant disadvantage is the large number of magnetic components, which directly leads to low power density, bulky equipment, and increased manufacturing costs.

[0029] Adjusting the winding spacing: This approach increases the distance between the primary and secondary windings of the transformer to generate leakage inductance. However, this approach is only suitable for applications with low leakage inductance requirements, and the difficulty in accurately controlling the leakage inductance value limits its application.

[0030] Additional leakage inductance column solution: To reduce the number of magnetic components, this solution incorporates additional leakage inductance columns into the transformer design to provide leakage inductance. While this approach reduces the overall number of magnetic components, it significantly increases the transformer's size, making height a particular issue in high-power applications. Furthermore, the additional leakage inductance column can cause excessive temperature rise in the transformer's internal windings, making heat dissipation difficult and potentially affecting the long-term stability of the equipment.

[0031] To address these shortcomings, magnetic integration technology emerged to address the challenges of high height, bulk, high losses, difficulty adjusting leakage inductance, and excessive electromagnetic compatibility (EMC). However, as operating frequencies continue to increase, the height of equipment systems is limited by the height of magnetic integrated components. Furthermore, magnetic core components suffer from high losses, high temperatures, difficulty dissipating heat, and excessive EMC, resulting in equipment reliability failing to meet performance requirements.

[0032] In view of this, an embodiment of the present application provides a planar transformer, which integrates the transformer and the inductor into an integrated design, and the windings of the planar transformer use printed circuit board (PCB) windings, that is, the windings of the planar transformer are all drawn using a PCB multilayer board, which can reduce the height of the magnetic integrated device and solve the problems of high loss of magnetic core devices, difficulty in heat dissipation due to temperature rise, and EMC exceeding the standard.

[0033] Specifically, the planar transformer includes a PCB winding and two magnetic cores. Each core includes a magnetic cover and a transformer column, an inductor column, and side columns mounted on the cover. The PCB winding is wound around the transformer and inductor columns. The transformer column, inductor column, and side columns of the two cores are arranged opposite each other. The magnetic cover and side columns surround the transformer column, inductor column, and PCB winding.

[0034] In an embodiment of the present application, the integration of the transformer and the inductor is achieved by arranging the transformer magnetic column and the inductor magnetic column on the magnetic cover, and the PCB winding is wound on the transformer magnetic column and the inductor magnetic column. The winding of the planar transformer adopts the PCB winding, so as to achieve the purpose of reducing the height of the planar transformer and reducing the volume of the planar transformer. Based on the planar design of the PCB winding, the magnetic core can also use an extremely small window height design, thereby improving the winding current density, improving the power density of the integrated magnetic component, greatly reducing the height dimension, reducing the overall volume, and reducing the total loss under high-frequency applications, so that the planar transformer meets the requirements of modular design. And the use of the PCB winding design has better heat dissipation. Furthermore, the purpose of optimizing EMC is achieved by surrounding the transformer magnetic column, the inductor magnetic column and the PCB winding with the magnetic cover and the side columns, that is, the magnetic core surrounds the PCB winding.

[0035] See also Figure 1 , Figure 1 The planar transformer 100 includes a PCB winding 10 and two magnetic cores, namely a first magnetic core 20 and a second magnetic core 30. The first magnetic core 20 and the second magnetic core 30 surround the PCB winding 10.

[0036] The first magnetic core 20 and the second magnetic core 30 have similar structures.

[0037] Please also refer to Figure 2 , Figure 2 This is an exploded view of a planar transformer provided in an embodiment of the present application. The first magnetic core 20 includes a first magnetic cover 21 and a transformer magnetic column 22, an inductor magnetic column 23, and a first side column 24 disposed on the first magnetic cover 21. The transformer magnetic column 22 and the inductor magnetic column 23 are disposed side by side on the first magnetic cover 21. The second magnetic core 30 includes a second magnetic cover 31 and a transformer magnetic column 33, an inductor magnetic column (not shown), and a second side column 32 disposed on the second magnetic cover 31. The transformer magnetic column 33 and the inductor magnetic column disposed on the second magnetic cover 31 can be disposed side by side. The first magnetic cover 21, the first side column 24, the second magnetic cover 31, and the second side column 32 surround the PCB winding 10.

[0038] I understand. Figure 2 The first magnetic core 20 shown includes a transformer magnetic column 22 and an inductor magnetic column 23 for example only. In other embodiments, any magnetic core in the planar transformer 100 may include one or more transformer magnetic columns and one or more inductor magnetic columns.

[0039] It is understood that the dimensions of the transformer and inductor columns can be designed according to the specific parameter requirements in actual applications. Figure 2The sizes of the transformer magnetic column 22 and the inductor magnetic column 23 are only examples. The transformer magnetic column may be larger, the inductor magnetic column may be larger, or the transformer magnetic column and the inductor magnetic column may be the same size. This application does not make any specific limitations on this.

[0040] In the embodiment of the present application, any side column of the two magnetic cores includes a lead opening 40. The PCB winding includes a coil wound around the transformer column and the inductor column and a lead passing through the lead opening 40.

[0041] Take the PCB winding set on the first magnetic core as an example, please refer to Figure 3 , Figure 3 Schematic diagram of the structure of the first magnetic core and PCB winding provided in an embodiment of the present application. The PCB winding 10 includes a coil 11 wound around the transformer column 22 and the inductor column 23 and a lead 12 passing through the lead opening 40.

[0042] I understand. Figure 3 The relationship between the PCB winding 10 and the first magnetic core 20 is only an example. The coil 11 of the PCB winding 10 wound on the transformer magnetic column and the inductor magnetic column can also be wound on the transformer magnetic column and the inductor magnetic column of the second magnetic core 30. The lead 12 of the PCB winding 10 can also pass through the lead opening 40 on the second magnetic core 30 (such as Figure 2 ).

[0043] I understand. Figure 2 as well as Figure 3 The division of the coils 11 , 111 , 112 and the lead wires 12 , 121 , 122 shown is merely an example.

[0044] Please also refer to Figures 4 and 5 , Figure 4 A side view of a planar transformer provided in an embodiment of the present application. Figure 5 This is a top view of the planar transformer provided in the embodiment of the present application. Figures 1 to 5 As shown, lead openings 40 are provided on both the first side pillar 24 and the second side pillar 32. All portions of the PCB winding 10 except the leads 12 are surrounded by the first magnetic cover 21, the first side pillar 24, the second magnetic cover 31, and the second side pillar 32. Only the leads 12 of the PCB winding 10 extend outside the magnetic core through the lead openings 40. In other words, the magnetic cover and side pillars of the planar transformer 100 completely surround all portions of the PCB winding 10 except the leads 12, such as the coils 11 wound around the transformer and inductor magnetic columns.

[0045] It can be understood that the lead-in port 40 can be used to lead out the wire or to lead in the wire. Figures 1 to 5 The dimensions of the lead-in opening 40 shown are merely examples and do not specifically limit the embodiments of the present application.

[0046] Take the first core as an example, please refer to Figure 2 The first side pillar 24 includes a first side pillar 241 and a second side pillar 242. One end of the first side pillar 241 and one end of the second side pillar 242 form a first lead-in opening 41, and the other end of the first side pillar 241 and the other end of the second side pillar 242 form a second lead-in opening 42. In other words, the lead-in opening 40 of the first side pillar 24 includes the first lead-in opening 41 and the second lead-in opening 42. The first lead-in opening 41 and the second lead-in opening 42 can be arranged opposite each other.

[0047] In the embodiment of the present application, the side columns of either side of the two magnetic cores include a first side column and a second side column. The side columns of either side of the two magnetic cores include a first lead-in opening and a second lead-in opening, that is, the lead-in openings of either side column include a first lead-in opening and a second lead-in opening.

[0048] like Figure 2 As shown, the PCB winding 10 includes a primary winding 101 and a secondary winding 102. The primary winding 101 is wound on the transformer magnetic column of the first magnetic core 20 and the second magnetic core 30, and the secondary winding 102 is wound on the transformer magnetic column 22 and the inductor magnetic column 23 of the first magnetic core 20 and the transformer magnetic column and the inductor magnetic column of the second magnetic core 30.

[0049] The primary winding 101 includes a coil 111 wound around the transformer's magnetic column and a first lead 121 passing through a first lead 41. The secondary winding 102 includes a coil 112 wound around the transformer's magnetic column and the inductor's magnetic column, and a second lead 122 passing through a second lead 42. The first magnetic cover 21 and the first side pillars 24 completely surround all portions of the PCB winding 10 except for the first lead 121 and the second lead 122. The magnetic covers (such as the first magnetic cover 21 and the second magnetic cover 31) and the side pillars (such as the first side pillars 24 and the second side pillars 32) completely surround all portions of the PCB winding 10 except for the first lead 121 and the second lead 122, that is, completely surround the coils 111 and 112 of the PCB winding 10.

[0050] I understand. Figure 2 The loop of the PCB winding 10 shown is only an example and is not specifically limited in this application.

[0051] Taking the first magnetic core as an example, Figure 6As shown, the transformer column 22 includes a first sidewall 221, a second sidewall 222, a third sidewall 223, and a fourth sidewall 224. The inductor column 23 includes a first sub-sidewall 231, a second sub-sidewall 232, a third sub-sidewall 233, and a fourth sub-sidewall 234. A first space 51 is formed between the first sidewall 221 and the first sub-sidewall 231. The first side column 241 includes a first side edge 2411, a second side edge 2412, and a third side edge 2413. A second space 52 is formed between the first side edge 2411 and the second sidewall 222, the second sub-sidewall 232, the first portion of the third sidewall 223, and the first portion of the third sub-sidewall 233. The second side column 242 includes a first sub-side edge 2421, a second sub-side edge 2422, and a third sub-side edge 2423. A third space 53 is formed between the first sub-side 2421 and the fourth sidewall 224, the fourth sub-sidewall 234, the second portion of the third sidewall 223, and the second portion of the third sub-sidewall 233. The first space 51, the second space 52, and the third space 53 are used to accommodate coils of the PCB winding 10, such as coils 111 and 112. A first lead 41 is formed between the second side 2412 and the second sub-side 2422, and a second lead 42 is formed between the third side 2413 and the third sub-side 2423. The first lead 41 and the second lead 42 are opposite each other. The first lead 41 faces the third portion of the third sidewall 223, and the second lead 42 faces the third portion of the third sub-sidewall 233.

[0052] It is understood that the arrangement of the transformer magnetic column, the inductor magnetic column and the side column of the second magnetic core 30 can also refer to Figure 6 .

[0053] In the embodiment of the present application, leakage inductance columns can be used in the magnetic core cavity to isolate the primary and secondary windings to achieve the integration of inductors and transformers, which is not specifically limited in the present application.

[0054] In the embodiment of the present application, the heights of the first inlet 41 and the second inlet 42 are expressed in millimeters.

[0055] For example, the first lead of the first magnetic core and the first lead of the second magnetic core are arranged opposite each other to form one lead opening. The second lead of the first magnetic core and the third lead of the second magnetic core are arranged opposite each other to form another lead opening. The height of the lead openings can be set based on the thickness of the PCB and a preset installation margin.

[0056] In some other embodiments, the height of the lead-in opening 40 is expressed in millimeters, and the height of the lead-in opening 40 ranges from 1 mm to 10 mm. In some other embodiments, the height of the lead-in opening 40 ranges from 4 mm to 8 mm.

[0057] It can be understood that the size of the lead-in port can be set according to actual conditions, and this application does not make any specific restrictions on this.

[0058] In an embodiment of the present application, the magnetic cover, the transformer magnetic column, the inductor magnetic column, and the side columns are integrally formed. Alternatively, the transformer magnetic column, the inductor magnetic column, and the side columns are bonded to the magnetic cover. Specifically, the magnetic core of the planar transformer can be composed of a pair of upper and lower integrally formed magnetic cores, or can be composed of the transformer magnetic column, the inductor magnetic column, and the side columns bonded between the first magnetic cover and the second magnetic cover, or can be composed of the transformer magnetic column, the inductor magnetic column, and the side columns bonded to the sides of the first magnetic cover and the second magnetic cover.

[0059] In the embodiment of the present application, the magnetic core material can be soft magnetic materials such as ferrite, amorphous, nanocrystalline, silicon steel, etc., and the present application does not make specific limitations on this.

[0060] In the embodiment of the present application, the PCB winding can be a multi-layer PCB winding. The transformer windings all adopt a planar design of PCB windings, so the magnetic core can also be designed with an extremely small window height.

[0061] In the embodiment of the present application, the inductor column is a separate winding column, so the inductance can be flexibly adjusted by adjusting the effective cross-sectional area and air gap of the inductor column without affecting the performance parameters of the transformer.

[0062] In the embodiments of the present application, magnetic columns, such as transformer columns and inductor columns, can be optionally air-gapped based on actual operating inductance requirements. The actual inductor value can be flexibly adjusted based on the effective cross-sectional area of the inductor column and the air gap. Therefore, in the embodiments of the present application, adjusting the inductor value does not require adding air gaps to the side columns, and there is no leakage flux that could affect EMC shielding effectiveness.

[0063] In the embodiment of the present application, the coil is wound by using transformer magnetic columns, inductor magnetic columns and PCB windings, and the side columns of the magnetic core on both sides and the upper and lower magnetic covers wrap the coil structure to shield the leakage flux, improve the consistency of the parasitic parameters of the magnetic device, and achieve the effect of optimizing EMC. Figures 1 to 5 As shown, except that the leads of the PCB winding pass through the smaller lead opening 40, the coils of the PCB winding are all in the closed magnetic core, and the magnetic cover and side columns of the magnetic core all wrap the coils of the primary and secondary windings, achieving a relatively ideal leakage flux shielding effect.

[0064] In the embodiments of the present application, the PCB winding manufacturing process is highly consistent, and the lead-in opening 40 does not need to consider the winding margin of conventional wire windings. The planar design of the PCB windings makes the winding thickness much smaller than that of wire windings, enabling the integration of transformers and inductors within a very small core window height. Compared to wire-wound magnetic devices, this further reduces the total system volume, significantly lowering the height of magnetic devices in high-power applications, eliminating height restrictions on magnetic devices in equipment, and meeting modular design requirements. Furthermore, the combination of PCB windings and magnetic cores requires only snapping the core onto the pre-processed PCB board, resulting in simple assembly and high consistency, improved manufacturing efficiency, and reduced magnetic device costs.

[0065] In the embodiment of the present application, the use of PCB windings can greatly improve the consistency of the parasitic parameters of the magnetic device and optimize the EMC consistency of the entire machine.

[0066] In the embodiments of the present application, the winding current density can be greatly improved, which greatly reduces the volume occupied by the winding, reduces the volume of the magnetic core, further reduces the loss of the magnetic device, and improves the loss density and efficiency. At the same time, the reduction in the amount of copper and the magnetic core also reduces the cost of the magnetic device. Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present application and are not limiting. In actual application, the entire content of the technical solution described in any embodiment of the present application can be implemented, or part of the content can be added, or part of the content can be deleted, or part of the content can be changed / replaced. Although the present application is described in detail with reference to the preferred embodiments, ordinary technicians in this field should understand that the technical solution of the present application can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present application.

Claims

1. A planar transformer, characterized in that: Includes PCB winding and two magnetic cores; Each of the magnetic cores includes a magnetic cover and a transformer magnetic column, an inductor magnetic column and a side column arranged on the magnetic cover; The PCB winding is wound on the transformer magnetic column and the inductor magnetic column; The transformer magnetic columns, the inductor magnetic columns and the side columns of the two magnetic cores are arranged opposite to each other; The magnetic cover and the side columns surround the transformer magnetic column, the inductor magnetic column and the PCB winding.

2. The planar transformer according to claim 1, wherein: The side column includes a lead opening, the PCB winding includes a coil wound on the transformer magnetic column and the inductor magnetic column and a lead passing through the lead opening, and the magnetic cover and the side column completely surround all parts of the PCB winding except the lead.

3. The planar transformer according to claim 1, wherein: The PCB winding includes a primary winding and a secondary winding, and the PCB winding is wound on the transformer column and the inductor column and includes: The primary winding is wound on the transformer magnetic column, and the secondary winding is wound on the transformer magnetic column and the inductor magnetic column.

4. The planar transformer according to claim 3, wherein: The side column includes a first lead and a second lead, the primary winding includes a coil wound on the transformer column and a first lead passing through the first lead, and the secondary winding includes a coil wound on the transformer column and the inductor column and a second lead passing through the second lead; The magnetic cover and the side pillars completely surround all parts of the PCB winding except the first lead and the second lead.

5. The planar transformer according to claim 2, wherein: The height of the lead-in opening is expressed in millimeters, and the height range of the lead-in opening is 4 mm to 8 mm.

6. The planar transformer according to claim 4, wherein: The transformer magnetic column and the inductor magnetic column are arranged in parallel on the magnetic cover.

7. The planar transformer according to claim 4, wherein: The side pillars include a first side pillar and a second side pillar; One end of the first side column and one end of the second side column form the first lead-in port; The other end of the first side column and the other end of the second side column form the second lead-in port.

8. The planar transformer according to claim 6, wherein: The transformer magnetic column includes a first side wall, a second side wall, a third side wall and a fourth side wall; The inductor column includes a first sub-side wall, a second sub-side wall, a third sub-side wall and a fourth sub-side wall, and a first space is formed between the first side wall and the first sub-side wall; The side pillars include a first side pillar and a second side pillar; The first side column includes a first side edge, a second side edge, and a third side edge, and a second space is formed between the first side edge and the second side wall, the second sub-side wall, the first portion of the third side wall, and the first portion of the third sub-side wall; The second side column includes a first sub-side, a second sub-side, and a third sub-side, wherein a third space is formed between the first sub-side, the fourth sidewall, the fourth sub-sidewall, the second portion of the third sidewall, and the second portion of the third sub-sidewall; The first space, the second space and the third space are used to accommodate the coils of the PCB winding; The first lead-in opening is formed between the second side and the second sub-side, and the second lead-in opening is formed between the third side and the third sub-side.

9. The planar transformer according to claim 8, wherein: The first lead is opposite to the third portion of the third sidewall, and the second lead is opposite to the third portion of the third sub-sidewall.

10. The planar transformer according to claim 1, wherein: The magnetic cover, the transformer magnetic column, the inductor magnetic column and the side columns are integrally formed; or, the transformer magnetic column, the inductor magnetic column and the side columns are bonded to the magnetic cover.

Images