CN216412794U - Planar transformer and circuit system - Google Patents

Abstract

The utility model discloses a planar transformer and a circuit system comprising the same. The planar transformer includes a transformer body and a package enclosing the transformer body. Wherein an outer shape of at least a portion of the package conforms to an outer shape of at least a portion of the transformer body. The planar transformer body is precisely packaged according to the appearance of the planar transformer body, so that the packaging area can be ensured to be as small as possible, the packaging material is saved, and the packaging cost is reduced.

Description

Planar transformer and circuit system

Technical Field

The present invention relates to a transformer, and more particularly, to a planar transformer with precise encapsulation and a circuit system including the planar transformer.

Background

In the production of modern devices (e.g., communication devices), small size, precision, and lightness and thinness have become the benchmark requirements. Therefore, a planar transformer applied thereto has appeared. The planar transformer is obtained by assembling the magnetic core and the winding. When the planar transformer works, the magnetic core and the winding of the planar transformer are exposed in a working environment and are in contact with air. In some cases, such exposure may affect the electrical performance of the planar transformer.

SUMMERY OF THE UTILITY MODEL

The technical problem to be solved by the embodiments of the present invention is to provide a precisely packaged planar transformer, which can isolate the planar transformer from the external environment, and at the same time, reduce unnecessary packaging materials and reduce the packaging cost.

In order to solve the above technical problem, the present invention provides a planar transformer, including: the transformer comprises a transformer body and a package for sealing the transformer body. An outer shape of at least a portion of the package conforms to an outer shape of at least a portion of the transformer body.

In one possible implementation, an outer surface of at least a portion of the package is a predetermined distance from an outer surface of at least a portion of the transformer body, the predetermined distance being 0.1mm to 10 mm.

In a feasible implementation mode, the package is obtained by molding the molding compound in a compression molding mode, or obtained by filling and curing the pouring sealant in a filling and curing mode.

In one possible implementation, the molding compound and/or the potting compound is made of an insulating heat sink material.

In one possible implementation, the surface of the package is provided with heat dissipation holes, and/or heat sinks.

In one possible implementation, the transformer body includes a planar winding and a magnetic core, the planar winding includes at least one magnetic core hole, and the magnetic core is embedded in the planar winding through the at least one magnetic core hole to complete assembly, so as to form the transformer body.

In one possible implementation, the magnetic core is made of a soft magnetic material and has one of the following shapes: cylindrical, donut-shaped, U-shaped, or E-shaped.

In one possible implementation, the connection ends of the planar winding are connected with pins exposed on the outer surface of the package.

In one possible implementation, the connection end of the planar winding is connected to the pin by welding.

The utility model also provides a circuit system comprising the planar transformer.

The implementation of the utility model has the following beneficial effects: the planar transformer can be precisely packaged according to the appearance of the planar transformer, the planar transformer can be protected from being influenced by the external environment, the packaging cost is reduced, and the packaging cost is reduced.

Drawings

Fig. 1A is an exemplary structural schematic diagram of a transformer body of a planar transformer, according to some embodiments of the utility model;

fig. 1B is another exemplary structural schematic diagram of a transformer body of a planar transformer, according to some embodiments of the utility model;

fig. 2A is an exemplary structural schematic of a planar transformer according to some embodiments of the present invention;

fig. 2B is another exemplary structural schematic of a planar transformer according to some embodiments of the present invention;

FIG. 3A is a schematic diagram of an exemplary configuration of another planar transformer, according to some embodiments of the utility model;

fig. 3B is another exemplary structural schematic of a planar transformer according to some embodiments of the present invention.

Reference numerals in the drawings: 100-transformer body, 110-magnetic core, 110-1-first magnetic core, 110-2-second magnetic core, 120-planar winding, 122-through opening, 130-connection end, 140-encapsulation, 150-pin.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only.

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

Fig. 1A is an exemplary schematic diagram of a transformer body of a planar transformer, according to some embodiments of the utility model. As shown in fig. 1A, the transformer body 100 includes a magnetic core 110, a planar winding 120, and a connection terminal 130. The magnetic core 110 may be made of a soft magnetic material. Exemplary soft magnetic materials may include pure iron, low carbon steel, iron silicon alloys, iron aluminum alloys, iron silicon aluminum alloys, nickel iron alloys, cobalt iron alloys, ferrite materials, iron based amorphous alloys, iron based nanocrystals, and the like. In some embodiments, the magnetic core 110 may have a shape. The shape may include a cylinder, donut, U-shape, E-shape, etc. In the example shown in fig. 1, the core 110 may be a U-shaped core that includes a set of cores disposed opposite each other: a first magnetic core 110-1 (which may also be referred to herein as an upper magnetic core 110-1) and a second magnetic core 110-2 (which may also be referred to herein as a lower magnetic core 110-2). It is understood that the shape of the magnetic core 110 of the transformer body 100 may be changed according to different application scenarios. The example in fig. 1 is for illustration purposes only.

The planar winding 120 may include at least one planar winding unit. Each planar winding unit may be an assembly in a fully cured state. For example, the planar winding unit may be prepared by means of circuit printing. After the insulating substrate is covered with a conductive material such as copper foil, the copper foil is etched according to a predetermined circuit diagram, an unnecessary copper foil portion is removed, and a conductive line is left, thereby obtaining a planar winding unit.

In some embodiments, the at least one planar winding unit may be stacked to form the planar winding. In some embodiments, the at least one planar winding unit is laminated to each other by an adhesive layer to form the planar winding unit. As an example, assuming a planar winding formed by stacking three planar winding units, the top surface of the planar winding unit at the lowest layer may be covered with an adhesive layer and then adhered integrally with the bottom surface of the planar winding unit at the middle layer. Similarly, the top surface of the planar winding unit in the middle layer can also be covered with a bonding layer, and the bonding layer is bonded with the bottom surface of the planar winding unit in the top layer into a whole, so that the planar winding is obtained. In some embodiments, the bonding layer may include an insulating adhesive, such as polyester, epoxy, polyurethane, polybutadienic acid, silicone, polyesterimide, polyimide, and the like.

In some embodiments, each planar winding unit may comprise at least one through opening. The through opening may match the shape of the magnetic core 110 to receive the magnetic core 110. Referring to fig. 1, the magnetic core 110 is a U-shaped magnetic core, and each of the planar winding units of the planar winding 120 has two through-holes. The shape of the through opening may be a shape matching the magnetic core 110. For example, the through-hole may be rectangular in shape. The through-opening of the planar winding unit may be pre-opened. For example, openings are made in predetermined positions on the insulating substrate according to the manufacturing requirements. When the planar winding units form a planar winding, the through-openings of each planar winding unit are aligned to form the magnetic core holes 122 of the planar winding. Through the core hole 122, the magnetic core 110 may smoothly pass through the core hole 122 during an assembly process of the transformer body.

The connection terminal 130 may be a passage through which the transformer body 100 is connected to an external device. For example, the transformer body 100 may be connected to a circuit board through the connection terminal 130 (e.g., connected to the circuit board as input and output terminals). In some embodiments, the connection end 130 may be implemented during the preparation of the planar winding. For example, a part of the copper foil not belonging to the coil constituting the winding is left at the time of etching. The portion of the copper foil is connected to the finally formed winding coil to form the connection terminal 130. In some embodiments, the connection end 130 may be disposed at an edge portion of the planar winding for subsequent connection with other components.

Fig. 1B is another exemplary structural schematic diagram of a transformer body of a planar transformer, according to some embodiments of the utility model. Fig. 1B is a side view of the assembled transformer body. The illustrated core 110 is a U-shaped core. After the assembly is completed, the vertical portions of the first and second magnetic cores 110-1 and 110-2 (which may also be referred to as the lower magnetic core 110-2 in this specification) are respectively inserted into the magnetic core holes 122. The horizontal portion is in contact with the planar winding. The side view may be a 90 degree rotated version similar to the "medium".

Fig. 2A and 2B are schematic diagrams of exemplary structures of planar transformers according to some embodiments of the present invention. Fig. 3A and 3B are schematic diagrams of another exemplary structure of a planar transformer according to some embodiments of the present invention. As shown in fig. 2A-3B, the planar transformer 200 may include a transformer body 100 and a package 140. The appearance of the package 140 is shown in dashed lines in fig. 2A and 3A. Fig. 2B and 3B show the outline of the planar transformer 200 after packaging.

In some embodiments, at least a portion of the package 140 conforms in outline to at least a portion of the transformer body 100. As shown in fig. 2A and 2B, the package 140 has an outer shape conforming to that of the transformer body 100. As shown in fig. 3A and 3B, the outer shape of the upper half of the package 140 corresponds to the outer shape of the upper half of the transformer body 100. It should be noted that fig. 2A-3B are merely exemplary illustrations, and that other variations are within the scope of the present invention. For example, the outer shape of the right half of the package 140 coincides with the outer shape of the right half of the transformer body 100.

In some embodiments, the package 140 may be formed by molding a molding compound. An exemplary molding compound may be an unsaturated polyester molding compound. After the transformer body 100 is obtained, the transformer body 100 may be wrapped in a molding compound. And then, the planar transformer 200 is obtained by extrusion molding through a pre-designed packaging mold.

In some embodiments, the package 140 may be obtained by filling and curing the potting adhesive. An exemplary potting adhesive may be an epoxy. After the transformer body 100 is obtained, the transformer body 10-may be placed in an encapsulation mold. And introducing pouring sealant into the packaging mold, and then packaging and curing to finally obtain the planar transformer 200.

In some embodiments, the molding compound and/or the potting compound may be made of an insulating heat sink material. The molding compound and/or pouring sealant obtained from any material with the functions are within the protection scope of the utility model.

In some embodiments, when the package 140 is formed outside the transformer body 100, a precise package mold may be designed according to the external shape of the transformer body 100. The encapsulation mold may be designed according to the shape of the transformer body 100 while being outwardly expanded by a certain distance. That is, after the encapsulation is completed, the encapsulation 140 is spaced apart from the portion of the transformer body 100 having the uniform outer shape by a certain distance. That is, at least a portion of the outer surface of the package 140 is a predetermined distance from the outer surface of at least a portion of the transformer body 100. The preset distance may be determined when designing the package mold. The preset distance may be as shown by h in fig. 2A and 3A. The predetermined distance may be any value from 0.1mm to 10 mm. For example 0.1mm, 0.5mm, 1mm, 5mm or 10 mm.

In some embodiments, the surface of the package 140 may be provided with thermal vias. For example, the surface of the package 140 may be perforated in a shape such as a circle, a regular hexagon, etc. This increases the contact area between the package 140 and the external environment, thereby improving the heat dissipation capability.

In some embodiments, a surface of the package 140 may be provided with a heat sink. For example, the heat sink may be disposed on the surface of the package 140 by means of thermal conductive silicone adhesive or physical fixation. The heat generated by the transformer body 100 during operation can be transferred to the heat sink through the contact surface between the package 140 and the heat sink, and then dissipated by the heat sink.

In some embodiments, the connection end 130 of the planar winding 120 may be connected to the pin 150. The connection terminal 130 may be connected to the pin 150 by soldering. After encapsulation, the leads 140 may be exposed at an outer surface of the encapsulation 140. It can also be said that a portion of the lead 140 can be exposed outside the package 140. For example, when the transformer body 100 is packaged, the package mold is provided with a through hole for allowing the pin 150 to pass through. After the planar winding 120 and the magnetic core 110 are assembled and fixed, and the connection end 130 and the pin 150 are connected, the pin 150 may extend out of the package mold through the through hole when the package mold is placed for packaging. Thus, the pins 150 of the planar transformer 200 after packaging can be located outside the package 140.

The planar transformer disclosed by the utility model realizes the isolation of the transformer body from the external environment through precise packaging, and ensures the stability of the normal operation of the transformer. Meanwhile, the packaging area is reduced by precise packaging, the packaging material is saved, and the packaging cost is reduced.

In another embodiment of the utility model, a circuit system is also disclosed. The circuitry may include the planar transformer described above.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the utility model. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims (10)

1. A planar transformer, comprising:

a transformer body; and

a package enclosing the transformer body;

wherein the content of the first and second substances,

the shape of at least a part of the package is consistent with the shape of at least a part of the transformer body;

the transformer body is connected with pins, and the pins are exposed on the outer surface of the package.

2. The planar transformer according to claim 1, wherein an outer surface of at least a portion of the encapsulation is at a predetermined distance from an outer surface of at least a portion of the transformer body, the predetermined distance being 0.1mm to 10 mm.

3. The planar transformer according to claim 1, wherein the encapsulation is obtained by compression molding of a molding compound or by filling and curing of a potting compound.

4. The planar transformer according to claim 3, wherein the molding compound and/or the potting compound is made of an insulating heat sink material.

5. The planar transformer according to claim 1, wherein the surface of the package is provided with heat dissipation holes, and/or heat sink fins.

6. The planar transformer of claim 1, wherein the transformer body comprises a planar winding and a magnetic core, the planar winding comprising at least one magnetic core hole, the magnetic core being assembled by embedding the planar winding through the at least one magnetic core hole to form the transformer body.

7. The planar transformer according to claim 6, wherein the magnetic core is made of a soft magnetic material and has one of the following shapes: cylindrical, donut-shaped, U-shaped, or E-shaped.

8. The planar transformer according to claim 6, wherein the connection ends of the planar windings are connected to the pins.

9. The planar transformer according to claim 8, wherein the connection ends of the planar windings and the pins are connected by soldering.

10. A circuit system, characterized in that it comprises at least a planar transformer according to any one of claims 1 to 9.

Images