Electronic Component And Method For Manufacturing An Electronic Component

Abstract

The electronic component comprises at least a first electronic element arranged inside a first casing of magnetic material and at least a second electronic element arranged inside a second casing of magnetic material. At least a first outer surface of the first casing and at least a second outer surface of the second casing are connected to each other with a non-magnetic layer and with at least one connection support. The connection support is adapted to be tension-resistant and is adapted and arranged such that the connection support substantially completely prevents an increase in a distance between the first outer surface and the second outer surface upon heating the non-magnetic layer.

Claims

1. Electronic component comprising at least a first electronic element arranged inside a first casing of magnetic material, at least a second electronic element arranged inside a second casing of magnetic material, wherein at least a first outer surface of the first casing and at least a second outer surface of the second casing are connected to each other with a non-magnetic layer and with at least one connection support, wherein the connection support is adapted to be tension-resistant and is adapted and arranged such that the connection support substantially completely prevents an increase in a distance between the first outer surface and the second outer surface upon heating the non-magnetic layer.

2. Electronic component according to claim 1, wherein the connection support is adapted to be compression-resistant and is adapted and arranged such that at least the connection support substantially completely prevents a reduction in the distance between the first outer surface and the second outer surface upon cooling the non-magnetic layer.

3. Electronic component according to claim 1, wherein the connection support is adapted to be torsion-resistant and/or the first outer surface and the second outer surface are connected together with at least two connection supports having a distance from each other.

4. Electronic component according to claim 1, wherein the connection support is formed as a material strip of sheet metal or plastic, wherein the material strip has a length which is greater than its width and wherein the material strip is embedded with a first longitudinal end of the material strip in the first casing and is embedded with a second longitudinal end of the material strip in the second casing.

5. Electronic component according to claim 1, wherein the connection support is electrically conductive and the connection support electrically connects the first electronic element to the second electronic element.

6. Electronic component according to claim 1, wherein the first casing and/or the second casing are prism-shaped or cylindrical, in particular with a triangular, square or circular cross-section.

7. Electronic component according to claim 1, wherein the first casing and/or the second casing comprise at least an electrical contact on at least one outer surface.

8. Electronic component according to claim 1, wherein the first casing and the second casing are arranged side by side.

9. Electronic component according to claim 1, wherein the first casing and the second casing are arranged one above the other.

10. Electronic component according to claim 1, comprising at least a third electronic element arranged inside a third casing of magnetic material, wherein the first casing and the second casing are arranged side by side and the third casing is arranged above the first casing and/or above the second casing.

11. Electronic component according to claim 1, wherein the non-magnetic layer has a thickness of at least 0.1 mm.

12. Electronic component according to claim 1, wherein the non-magnetic layer comprises an epoxy.

13. Method for manufacturing an electronic component according to claim 1, comprising the step: embedding section by section of the connection support into the first casing, the second casing and/or the third casing.

14. Method according to claim 13, wherein the embedding takes place during the production of the first casing, the second casing and/or the third casing.

15. Method according to claim 13, wherein the at least one connection support is part of a lead frame for providing electrical contacts of the electronic component and wherein the method comprises the step: at least partially embedding of the lead frame in the first casing, the second casing and/or the third casing.

16. Method according to claim 15, comprising the step: separation of the connection support and/or the electrical contacts from the lead frame.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The drawings show:

[0035] FIG. 1 an oblique view from top of an inventive electronic component,

[0036] FIG. 2 an oblique view from bottom of the electronic component of FIG. 1,

[0037] FIG. 3 the view from FIG. 2 without a first casing and a second casing,

[0038] FIG. 4 an oblique view from bottom of another embodiment of an inventive electronic component without a first casing, a second casing and electrical contacts,

[0039] FIG. 5 an oblique view from top of another embodiment of an inventive electronic component comprising a third casing arranged side by side to a first casing and to a second casing,

[0040] FIG. 6 an oblique view from top of another embodiment of an inventive electronic component comprising a third casing arranged above a first casing and to a second casing,

[0041] FIG. 7 an oblique view from top of the electronic component of FIG. 6 without the third casing,

[0042] FIG. 8 an oblique view from bottom of the electronic component of FIG. 6 without the first casing, the second casing and the third casing, and

[0043] FIG. 9 the oblique view from FIG. 2 from another perspective.

DETAILED DESCRIPTION

[0044] FIG. 1 shows an electronic component 10 according to the invention from top. The electronic component 10 comprises a first casing 22 and second casing 32. Each casing 22, 32 consists of magnetic material or comprises magnetic material, in particular each casing 22, 32 is a molded casing of iron powder or ferrite powder. The iron powder or ferrite powder may be mixed with binder, e.g. resin and hardener, or may be sintered. The first casing 22 is arranged side-by-side to the second casing 32, wherein the first casing 22 comprises a first outer surface 24 and the second casing 32 comprises a second outer surface 34. Both outer surfaces 24, 34 face each other and are arranged parallel to each other. A distance 60 between both outer surfaces 24, 44 amounts to 0.1 and is advantageously in a range between 0.1 mm and 0.4 mm. The first casing 22 and a second casing 32 are of cuboid shape.

[0045] The first casing 22 and the second casing 32 are mechanically connected together at their outer surfaces 24, 34 by means of a non-magnetic layer 40 in form of a glue and also by means of two connection supports 50, 52, which are not visible in FIG. 1 and which will be explained in conjunction with FIG. 3. In particular, both casings 22, 32 are glued together with an epoxy acting as the non-magnetic layer 40. Thus, a thickness of the non-magnetic layer 40 and the distance 60 are equal. In other words, the non-magnetic layer 40 has thickness of 0.1 mm. The non-magnetic layer 40 is magnetically insulating, such that a magnetic flux from the first casing 22 or from the second casing 42 cannot pass the non-magnetic layer 44 or at least the magnetic flux is significantly reduced when the magnetic flux passes the non-magnetic layer 44.

[0046] The first casing 22 and the second casing 32 comprise electrical contacts 80, 86. The electrical contacts 80, 86 are adapted to be connected to a printed circuit board not shown in FIG. 1, in particular by soldering electrical contacts 80, 86 of the electronic component 10 to the corresponding contact pads of a printed circuit board.

[0047] FIG. 2 shows the electronic component 10 of FIG. 1 from below. The first casing 22 comprises first recesses 81 and the second casing 42 comprises second recesses 87. The first recesses 81 and the second recesses 87 are arranged at an underside of the first casing 22 and the second casing 32, respectively. The recesses 81, 87 are adapted to receive at least a section of the electrical contacts 80, 86. Each of the first recesses 81 is adapted to receive the section of two electrical contacts 80, said section being parallel to the underside of the first casing 22, and each of the second recesses 87 is adapted to receive the section of one single electrical contact 86, said section being parallel to the underside of the second casing 32. In an embodiment not shown a recess might be adapted to receive the sections of more than two electrical contacts, in particular three, four or five electrical contacts. A depth of the recesses 81, 87 is chosen so that the sections of the electrical contacts 80, 86 do not protrude from the underside of the first casing 22 and the second casing 32, respectively. Further, the electrical contacts 80, 86 comprise a section which is arranged parallel to outer surfaces of the first casing 22 and the second casing 32.

[0048] FIG. 3 shows the electronic component 10 of FIG. 2 without the first casing 22 and the second casing 32. A first electronic element 20 is arranged inside the first casing 22 and a second electronic element 30 is arranged inside the second casing 32. The first electronic element 20 is embodied as three concentric coils, wherein each coil is electrically connected to two electrical contacts 80. The second electronic element 30 is embodied as a single coil, wherein the coil is electrically connected to two electrical contacts 86. The electrical contacts 80 comprise a section partly arranged inside the first casing 22 so that electrical connections between the electrical contacts 80 and the coils of element 20 are arranged inside the first casing 22. The electrical contacts 86 are partly arranged inside the second casing 32 such that the electrical connection between the electrical contacts 86 and the electronic element 30 is arranged inside the casing 32. There is no electrical connection between the first electronic element 20 and the second electronic element 30.

[0049] The non-magnetic layer 40 magnetically isolates the coils of the first electronic element 20 and the coil of the second electronic element 30 from each other, such that the first electronic element 20 does not interfere with the second electronic element 30 and vice versa.

[0050] The electronic component 10 comprises two connection supports 50, 52 positioned at a distance from each other and penetrating the non-magnetic layer 40. Each connection support 50, 52 is formed as a material strip of sheet metal, e.g. made of cooper, having a length 70 and the width 72. The length 70 is greater than the width 72. A first longitudinal end 74 of each connection support 50, 52 is embedded inside the first casing 22 for mechanically connecting the first outer surface 24 and a second longitudinal end 76 of each connection support 50, 52 is embedded inside the second casing 32 for mechanically connecting the second outer surface 34. Thus, the first outer surface 24 and the second outer surface 34 are mechanically connected to each other by means of the connection supports 50, 52 and in addition by means of the non-magnetic layer 40. Each connection support 50, 52 comprises a middle section arranged between the first longitudinal end 74 and the second longitudinal end 76, wherein the middle section is surrounded by the non-magnetic layer 40. Accordingly, each connection support 50,52 pierces the non-magnetic layer 40.

[0051] Each of the connection supports 50, 52 is tension-resistant. It might be the case that tensile forces between the first casing 22 and the second casing 32 occur, in particular between the first outer surface 24 and the second outer surface 34. The origin of the tensile forces might be an increase in temperature, which is observed when the electronic component 10 is soldered to a printed circuit board. In detail, during soldering a temperature of the non-magnetic layer 40 increases, which then expands upon heating. Since the non-magnetic layer 40 comprises a higher thermal expansion coefficient compared to the connection supports 50, 52, the thermal expansion of the non-magnetic layer 40 is higher than the thermal expansion of the connection supports 50, 52. The difference in thermal expansion of the non-magnetic layer 40 and the connection supports 50, 52 leads to tensile forces applied on the connection supports 50, 52. Since the connection supports 50, 52 are tension-resistant, the connection supports 50, 52 sustain the tensile forces without any deformation or with a neglectable extension in a direction of the tensile force of less than 5%, in particular 3%, in particular 2%, in particular 1%. Accordingly, the distance 60 between the first casing 22 and the second casing 32 does not increase or increases only in a neglectable manner and thus the electrical contacts 80, 86 stay in their position allowing reduced manufacturing tolerances and a compact design of the electronic component 10. Especially, soldering to a printed circuit board is possible, since the electrical contacts 80, 86 of the electronic component 10 do not change their relative position when the electrical component 10 is heated up during soldering.

[0052] Each of the connection supports 50, 52 is also compression-resistant. It might be the case that pressure forces between the first casing 22 and the second casing 32 occur, in particular between the first outer surface 24 and the second outer surface 34. The origin of the pressure forces might be a decrease in temperature, which is observed during production of the electrical connection between the electronic component 10 and a printed circuit board. The non-magnetic layer 40 contracts, when a temperature of the non-magnetic layer 40 decreases. Since the non-magnetic layer 40 comprises a higher thermal expansion coefficient compared to the connection supports 50, 52, the thermal contraction of the non-magnetic layer 40 is higher than the thermal contraction of the connection supports 50, 52. The difference in thermal contraction of the non-magnetic layer 40 and the connection supports 50, 52 leads to pressure forces applied on the connection supports 50, 52. Since the connection supports 50, 52 are compression-resistant, the connection supports 50, 52 sustain the pressure forces without any deformation or with a neglectable contraction in a direction of the pressure force of 3%, in particular 1%. Accordingly, the distance 60 between the first casing 22 and the second casing 32 does not decrease or decreases only in a neglectable manner and thus the electrical contacts 80, 86 stay in their position allowing reduced manufacturing tolerances and a compact design of the electronic component 10. Especially, there is no risk that a soldering connection between the contacts 80, 86 of the electrical component 10 and a printed circuit board breaks up when cooling down the electrical component 10 after soldering.

[0053] FIG. 4 shows a second embodiment of the electronic component 10 without a first casing, without a second casing and without electrical contacts. For a better understanding of identical and functionally equivalent elements, the same reference signs are used and in this respect reference is made to the above description of the embodiment shown in FIGS. 1 to 3, so that only the existing differences are discussed. The electronic component 10 of FIG. 4 comprises two electrically conductive connection supports 50, 52. The connection supports 50, 52 are electrically connected to a first electronic element 20 and to a second electronic element 30. In detail, the first electronic element 20 comprises four coils and the second electronic element 30 comprises two coils. One end of a coil of the first electronic element 20 is electrically connected to the first connection support 50. The other end of the same coil or one end of another coil of the first electronic element 20 is electrically connected to the second connection support 52. Additionally, one end of a coil of the second electronic element 30 is electrically connected to the first connection support 50 and another end of the same coil or one end of another coil of the electronic element 30 is electrically connected to the second connection support 52. Thus, two coils of the first electronic element 20 are electrically connected to one coil of the second electronic element 30. In any case at least one of the connection supports 50, 52 can be used for an electrical connection between the first electronic element 20 and the second electronic element 30. FIG. 5 shows a further embodiment of the electronic component 10. The electrical component 10 comprises a first casing 22, a second casing 32 and a third casing 92, wherein a first electronic element is arranged inside the first casing 22, a second electronic element is arranged inside the second casing 32 and a third electronic element is arranged inside the third casing 92. All casings 22, 32, 92 are arranged side-by-side so that the undersides of all casings 22, 32, 92 are aligned to each other or are flush with each other and all casings 22, 32, 92 are connected with a non-magnetic layer 40 to each other. A longitudinal length of the first casing 22 is equal to a length of second casing 32 and third casing 92 being connected with the non-magnetic layer 14. The electronic component 10 is of cuboid shape. The non-magnetic layer 14 is t-shaped.

[0054] The electronic components 10 according to the embodiment of FIG. 5, according to the embodiment of FIGS. 1 to 3 and according to the embodiment of FIG. 4 are manufactured by a one-time molding process. The casings 22, 32, 92 consist of a mixture of magnetic powder in form of iron powder and glue, wherein the mixture is pressed together and at the same time heated. Before pressing the mixture, the connection supports 50, 52 are embedded inside the mixture of the casings 22, 32, 92.

[0055] FIG. 6 shows a further embodiment of the electronic component 10. The embodiment of FIG. 6 differs from the embodiment in FIGS. 1 to 3 in that a third casing 92 is arranged above a first casing 22 and above a second casing 32.

[0056] The third casing 92 comprises electrical contacts 94. The electrical contacts 94 are adapted to be connected to a printed circuit board not shown in FIG. 6, in particular by soldering the electronic component 10 to the printed circuit board. A section of the electrical contacts 94 is arranged in a first recess 81 of the underside of first casing 22. A further section of the electrical contacts 94 is arranged at an outer surface of the first casing 22 and the third casing 92.

[0057] FIG. 7 shows the electronic component 10 of FIG. 6 without the third casing and without the electronic element arranged inside the third casing. The electronic component 10 comprises a first connection support 54 arranged between the third casing 92 and the first casing 22 and a second connection support 56 arranged between the third casing 92 and second casing 32. Each of the connection supports 54, 56 is embodied as squared rod being tension-resistant and torsion-resistant.

[0058] FIG. 8 shows the electronic component 10 of FIG. 7 from below without the first casing 22, without the second casing 32 and without the third casing 92. The connection supports 54, 56 pierce or penetrate the non-magnetic layer 40.

[0059] FIG. 9 shows the electronic component 10 of FIG. 8 from another perspective.

[0060] The electronic component 10 shown in FIGS. 6 to 9 is manufactured by two-time molding process or two step molding process. In a first step the electronic elements 20, 30 are electrically connected to a lead frame providing the electrical contacts 80, 86 and connection supports 50, 52. In a second step the electronic elements 20, 30 and the connection supports 50, 52, 54, 56 are embedded with the material of the casings 22, 32. The material of the casings 22, 32 is a mixture of magnetic powder in form of iron powder and binder, especially glue. At this state the material of the casings 22, 32 is flexible and easy to form. As a third step the casings 22, 32 are molded, e.g. by pressing, heating and/or curing the material of casings 22, 32. As a fourth step the connection supports 50, 52 and the electrical contacts 80, 86 are separated from the lead frame and the electrical contacts 80, 86 are bent, such that sections of the electrical contacts 80, 86 are arranged inside their corresponding recesses 81, 87. As a fifth step the electronic element which will be arranged inside the third casing 92, is electrically connected to a further lead frame. In a sixth step the electronic element is embedded with the material of the third casing 92. As a seventh step the casing 92 is molded. As an eight step the electrical contacts 94 are separated from the lead frame and are bent, such that the electrical contacts 94 are arranged inside their corresponding recess 81. As a ninth step the non-magnetic layer 40 is manufactured by filling the space between the casings 22, 32, 92 with glue.

[0061] The invention makes it possible to fabricate the electronic component according to a modular principle allowing a high flexibility. For example, the electronic component can be individually manufactured depending on the application, wherein multiple different electronic elements can be integrated in the electronic component. As an advantage, instead of soldering each electronic element separately on a printed circuit board, the electronic component is soldered on the printed circuit board in a single soldering process, wherein all electronic elements of the electronic component are soldered in a single soldering step. Accordingly, the inventive electronic component is suitable for automatic soldering. Thus, the embodiments shown in the figures and explained above make clear, that the invention provides an electronic component having a compact design with higher power density and high current capability and being suitable for automatic soldering and the invention further provides a method for manufacturing the electronic component.