Multi-layer composite coil structure, inductor and transformer

Abstract

The utility model provides a multilayer composite coil structure, an inductor and a transformer, the multilayer composite coil structure comprises two sub-coils which are laminated, and a welding layer is arranged between the adjacent sub-coils. The sub-coil comprises a first conductive film, an insulating film arranged on the first conductive film and a second conductive film arranged on the insulating film, the insulating film comprises at least one through hole, and a contact is arranged in the through hole, so that the first conductive film and the second conductive film located on the two sides of the insulating film are in electric contact; and the through holes in the adjacent insulating films are distributed in a staggered manner. The first conductive film and the second conductive film on the two adjacent sides of the welding layer are both single circles; the number of turns of the first conducting film on the bottom layer and / or the number of turns of the second conducting film on the top layer are / is larger than or equal to 2. Meanwhile, compared with a single-circle multi-layer coil with the same layer number, the number of turns of the coil is increased, and the inductance of a product is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of electronic components, and particularly relates to a multi-layer composite coil structure, an inductor and a transformer. Background Art

[0002] With the rapid development of electronic technology, the performance requirements for inductance coils are increasing day by day, especially in terms of miniaturization, high inductance, low loss and high saturation current, etc., which pose more stringent challenges. At present, the mainstream thin-film inductance coil designs on the market are mainly divided into two categories: multi-layer single-turn structure and double-layer multi-turn structure. Multi-layer single-turn structure: This type of design etches single-turn double-layer coils on both sides of an insulating film through multi-layer conductive films, and a multi-layer single-turn structure is formed by stacking and welding several single-turn double-layer coils; Double-layer multi-turn structure: Multi-layer thin films are respectively etched into multi-turn coils on both sides of the insulating film. However, due to the aspect ratio problem of etching, the coils of the double-layer multi-turn structure cannot be made high enough. If multi-layer multi-turn coils are manufactured, and several double-layer multi-turn coils are stacked and welded, since the number of coil layers increases and each layer needs to be closely arranged to achieve efficient electromagnetic conversion, interlayer insulation has become a technical obstacle that is difficult to overcome.

[0003] Therefore, there is an urgent need for a multi-layer composite coil structure that can effectively solve the multi-layer multi-turn insulation problem while ensuring efficient electromagnetic conversion. Summary of the Utility Model

[0004] In order to solve the above problems, the purpose of the utility model is to provide a multi-layer composite coil structure, in which the top layer and the bottom layer are set as multi-turn coils, and the middle layer is set as a single turn to increase the number of layers while avoiding insulation problems; or reduce the number of turns in the middle layer and increase the line spacing in the middle layer at the same time, so as to effectively reduce the risk of short circuit caused by the solder paste flowing into the coil gap in the middle layer while increasing the number of turns.

[0005] The utility model is realized through the following technical solutions:

[0006] A multi-layer composite coil structure includes:

[0007] Sub-coils, at least two sub-coils are stacked;

[0008] A welding layer, the welding layer is arranged between adjacent sub-coils;

[0009] The sub-coil includes a first conductive film, an insulating film arranged on the first conductive film, and a second conductive film arranged on the insulating film. The insulating film includes at least one through hole, and a contact is arranged in the through hole to enable electrical contact between the first conductive film and the second conductive film on both sides of the insulating film; the through holes on adjacent insulating films are arranged in a staggered manner;

[0010] Among them, the number of turns of the first conductive film and the number of turns of the second conductive film on both sides of the same welding layer are the same; the first conductive film and the second conductive film on both adjacent sides of the welding layer are single-turn; the number of turns of the first conductive film at the bottom layer and / or the number of turns of the second conductive film at the top layer is greater than or equal to 2.

[0011] A multi-layer composite coil structure includes:

[0012] Sub-coils, at least two sub-coils are stacked;

[0013] A welding layer, the welding layer is arranged between adjacent sub-coils;

[0014] The sub-coil includes a first conductive film, an insulating film arranged on the first conductive film, and a second conductive film arranged on the insulating film. The insulating film includes at least one through hole, and a contact is arranged in the through hole so that the first conductive film and the second conductive film on both sides of the insulating film are in electrical contact; the through holes on adjacent insulating films are distributed in a staggered manner;

[0015] Among them, the number of turns of the first conductive film and the number of turns of the second conductive film on both sides of the same welding layer are the same; the number of turns of the first conductive film at the bottom layer is greater than 2; the number of turns of the first conductive film on both sides of the welding layer is less than the maximum number of turns of the first conductive film at the bottom layer and the second conductive film at the top layer, and the line pitch is greater than the line pitch of the conductive film.

[0016] Further, the through hole corresponds to the end of the first conductive film and the starting end of the second conductive film.

[0017] Further, the total line widths of the first conductive film and the second conductive film are the same.

[0018] Further, the number of turns of the first conductive film at the bottom layer is the same as the number of turns of the second conductive film at the top layer.

[0019] Further, the starting ends and the ending ends of the first conductive film and the second conductive film on both adjacent sides of the welding layer are respectively aligned.

[0020] Further, the starting end of the first conductive film at the bottom layer and the ending end of the second conductive film at the top layer are respectively located on opposite sides of the sub-coil.

[0021] An inductor includes the above multi-layer composite coil structure.

[0022] A transformer includes the above multi-layer composite coil structure.

[0023] Compared with the prior art, the technical solution and its beneficial effects of the present utility model are as follows:

[0024] (1) The multi-layer composite coil structure of the present utility model sets the top layer and the bottom layer as multi-turn coils, and the middle layer as a single-turn coil, thus avoiding the problem of inter-wire insulation in the middle layer. At the same time, compared with a single-turn multi-layer coil of the same number of layers, the number of coil turns is increased, and the inductance of the product is improved.

[0025] (2) The multi-layer composite coil structure of the present utility model sets the top layer and the bottom layer as multi-turn coils, the number of turns in the middle layer is less than that of the top layer and the bottom layer, and the wire spacing in the middle layer is increased, thus effectively reducing the risk of short circuit caused by solder paste flowing into the coil gap in the middle layer while increasing the number of turns. Description of the Drawings

[0026] Figure 1 is a cross-sectional view of a multi-layer composite coil structure provided by an embodiment of the present utility model;

[0027] Figure 2 is a top view of the first conductive film of the first sub-coil provided by an embodiment of the present utility model;

[0028] Figure 3 is a top view of the second conductive film of the first sub-coil provided by an embodiment of the present utility model;

[0029] Figure 4 is a top view of the first conductive film of the second sub-coil provided by an embodiment of the present utility model;

[0030] Figure 5 is a top view of the second conductive film of the second sub-coil provided by an embodiment of the present utility model;

[0031] Figure 6 is a top view of the first conductive film of the third sub-coil provided by an embodiment of the present utility model;

[0032] Figure 7 is a top view of the second conductive film of the third sub-coil provided by an embodiment of the present utility model.

[0033] Illustration:

[0034] Sub-coil - 10; First conductive film - 11; Second conductive film - 12; Insulating film - 13; Contact point - 14; Welding layer - 20; First electrode terminal - 30; Second electrode terminal - 31;

[0035] First sub-coil - 100; First contact point - 101; Second sub-coil - 200; Second contact point - 201; Third sub-coil - 300; Third contact point - 301. Detailed Embodiment

[0036] To make the objectives, technical solutions, and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Apparently, the described embodiments are some but not all of the embodiments of the present utility model. It should be understood that the specific embodiments described herein are only used to explain the present utility model and are not used to limit the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts fall within the protection scope of the present utility model.

[0037] Referring to Figure 1 , a multi-layer composite coil structure includes at least two sub-coils 10 stacked on top of each other, and the sub-coils are connected by a welding layer 20 therebetween.

[0038] Each sub-coil 10 includes a first conductive film 11, an insulating film 13 disposed on the first conductive film 11, and a second conductive film 12 disposed on the insulating film 13. The insulating film includes at least one through hole (not shown), and a contact 14 is disposed in the through hole so that the first conductive film 11 and the second conductive film 12 on both sides of the insulating film 13 are in electrical contact. In this embodiment, the position of the through hole corresponds to the end of the first conductive film and the start of the second conductive film, so that the current flow path is the longest, and the cancellation of magnetic induction lines caused by the reverse current of redundant coils is also avoided.

[0039] The number of turns of the first conductive film and the number of turns of the second conductive film on both sides of the same welding layer 20 are the same, so as to orderly transfer the current of the first conductive film at the bottom layer layer by layer to the second conductive film at the top layer. In this embodiment, the first conductive film and the second conductive film on both adjacent sides of the welding layer are both single-turn, thus avoiding the problem of insulation between lines in the middle layer. At the same time, within the same size as the traditional coil, the total number of turns of the multi-layer single-turn is exceeded, so as to manufacture products with a larger performance range, and at the same time, the utilization rate of the magnetic material winding window is higher than that of the multi-layer single-turn. It can be understood that the through holes on adjacent insulating films are staggered to avoid short-circuiting the conductive films.

[0040] In this embodiment, the total line widths of the first conductive film and the second conductive film are the same. It can be understood that the total line width refers to the total width from the inner edge to the outer edge of the conductive film, which improves the overall stability of the coil structure. The start ends and the end ends of the first conductive film and the second conductive film on both adjacent sides of the welding layer are respectively aligned. The number of turns of the first conductive film at the bottom layer is the same as the number of turns of the second conductive film at the top layer.

[0041] Taking the welding of three sub-coils to form a four-layer coil structure as an example, this embodiment will be further explained.

[0042] Referring to Figure 2 and Figure 3, the first conductive film 110 of the first sub-coil 100 is a three-turn conductive film. The current flows in from the head end (the first electrode end 30) and flows out from the end of the first conductive film 110. A first contact 101 is provided at the position corresponding to the end of the first conductive film. Through the first contact 101, the current flows to the starting end of the second conductive film 120 and flows along the second conductive film to the end of the second conductive film 120. The second conductive film 120 of the first sub-coil 100 is a single-turn conductive film.

[0043] See Figure 4 and Figure 5 , the first conductive film 210 of the second sub-coil 200 is the same as the second conductive film 120 of the first sub-coil 100, which is a single-turn conductive film, and the starting end and the end are respectively aligned. When the first conductive film 210 of the second sub-coil 200 is connected to the second conductive film 120 of the first sub-coil 100 through the welding layer 20 formed by heating solder, the current of the second conductive film 120 of the first sub-coil 100 also flows from the starting end to the end along the first conductive film 210 of the second sub-coil 200. A second contact 201 is provided at the position corresponding to the end of the first conductive film 210 of the second sub-coil 200. Through the second contact, the current flows to the starting end of the second conductive film 220 of the second sub-coil 200 and flows along the second conductive film 220 to the end of the second conductive film. In this embodiment, the second conductive film 220 of the second sub-coil 200 is a single turn.

[0044] See Figure 6 and Figure 7 , the first conductive film 310 of the third sub-coil 300 is the same as the second conductive film 220 of the second sub-coil 200, which is a single-turn conductive film, and the starting end and the end are respectively aligned. When the first conductive film 310 of the third sub-coil 300 is connected to the second conductive film 220 of the second sub-coil 200 through the welding layer formed by heating solder, the current of the second conductive film 220 of the second sub-coil also flows from the starting end to the end along the first conductive film 310 of the third sub-coil. A third contact 301 is provided at the position corresponding to the end of the first conductive film 310 of the third sub-coil. Through the third contact, the current flows to the starting end of the second conductive film of the third sub-coil and flows along the second conductive film 320 to the end of the second conductive film. In this embodiment, the second conductive film 320 of the third sub-coil 300 has the same number of turns as the first conductive film 110 of the first sub-coil 100. The end (the second electrode end 31) of the second conductive film 320 of the third sub-coil extends from the other side opposite to the starting end of the first conductive film of the first sub-coil, so that the two electrode ends are respectively located on both sides of the coil body.

[0045] It can be seen that with the structure of the present utility model, the three sub-coils 10 form a four-layer coil structure. This four-layer coil structure includes 8 coils (3 coils in the bottom layer, 1 coil in each of the second and third layers, and 3 coils in the top layer). While for a traditional single-layer multi-turn structure to obtain an 8-turn coil structure, seven sub-coils need to be stacked. Under the condition of the same required number of turns and maintaining roughly the same performance, the composite coil structure of the present utility model can reduce the usage of sub-coils, thereby effectively reducing the cost and lowering the height of the product, providing conditions for the miniaturization of the product.

[0046] It should be noted that the single turn mentioned in this embodiment is not limited to a full turn. For example, a single turn can be four-fifths of a turn, five-sixths of a turn, etc., so as to refine the accuracy of the number of coil turns, better match the required designed inductance value, cover all inductance values of products on the market, and have a wide range of applications.

[0047] In other embodiments, the number of turns of the first conductive film in the bottom layer and / or the number of turns of the second conductive film in the top layer is greater than 2. The number of turns of the first conductive film on both sides of the welding layer is less than the maximum number of turns of the first conductive film in the bottom layer and the second conductive film in the top layer, and the line pitch is greater than the line pitch of this conductive film, so as to effectively reduce the risk of short circuit caused by solder paste flowing into the coil gap in the middle layer while increasing the number of turns. Usually, the number of turns of the first conductive film and the second conductive film on both sides of the welding layer can be two turns.

[0048] This embodiment also provides an inductor, including the above-mentioned multi-layer composite coil structure.

[0049] This embodiment also provides a transformer, including the above-mentioned multi-layer composite coil structure.

[0050] The above description shows and describes the preferred embodiments of the present utility model. It should be understood that the present utility model is not limited to the form disclosed herein, should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be changed within the scope of the concept of the present utility model herein through the above teachings or the technology or knowledge in related fields. And any changes and modifications made by those skilled in the art without departing from the spirit and scope of the present utility model should fall within the protection scope of the appended claims of the present utility model.

Claims

1. A multi-layer composite coil structure, characterized in that, Comprising: Sub-coils, with at least two sub-coils stacked; A welding layer disposed between adjacent sub-coils; The sub-coil includes a first conductive film, an insulating film disposed on the first conductive film, and a second conductive film disposed on the insulating film. The insulating film includes at least one through-hole, and a contact is disposed in the through-hole to enable electrical contact between the first conductive film and the second conductive film on both sides of the insulating film; the through-holes on adjacent insulating films are misaligned; Wherein, the first conductive film and the second conductive film on both sides of the welding layer are both single-turn; the number of turns of the first conductive film at the bottom layer and / or the number of turns of the second conductive film at the top layer is greater than or equal to 2.

2. A multi-layer composite coil structure, characterized in that, Comprising: Sub-coils, with at least two sub-coils stacked; A welding layer disposed between adjacent sub-coils; The sub-coil includes a first conductive film, an insulating film disposed on the first conductive film, and a second conductive film disposed on the insulating film. The insulating film includes at least one through-hole, and a contact is disposed in the through-hole to enable electrical contact between the first conductive film and the second conductive film on both sides of the insulating film; the through-holes on adjacent insulating films are misaligned; Wherein, the number of turns of the first conductive film and the number of turns of the second conductive film on both sides of the same welding layer are the same; the number of turns of the first conductive film at the bottom layer and / or the number of turns of the second conductive film at the top layer is greater than 2; the number of turns of the first conductive film on both sides of the welding layer is less than the maximum number of turns of the first conductive film at the bottom layer and the second conductive film at the top layer, and the line pitch is greater than the line pitch of the conductive film.

3. A multi-layer composite coil structure according to claim 1 or 2, characterized in that, The through-hole corresponds to the end of the first conductive film and the start of the second conductive film.

4. A multi-layer composite coil structure according to claim 1 or 2, characterized in that, The total line widths of the first conductive film and the second conductive film are the same.

5. A multi-layer composite coil structure according to claim 1 or 2, characterized in that, The number of turns of the first conductive film at the bottom layer is the same as the number of turns of the second conductive film at the top layer.

6. A multi-layer composite coil structure according to claim 1 or 2, characterized in that The start ends and the end ends of the first conductive film and the second conductive film on both sides of the welding layer are respectively aligned.

7. A multi-layer composite coil structure according to claim 1 or 2, characterized in that, The start end of the first conductive film at the bottom layer and the end end of the second conductive film at the top layer are respectively located on opposite sides of the sub-coil.

8. An inductor, characterized in that, Comprising the multi-layer composite coil structure according to any one of claims 1 to 7.

9. A transformer, characterized in that, Comprising the multi-layer composite coil structure according to any one of claims 1 to 7.

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