Inductive component and high-frequency filter device

Abstract

The invention relates to an inductive component having a planar conductive track structure. The planar conductive track structure is surrounded along a predetermined section by a ferromagnetic core. For targeted control of the current flow inside the planar conductive track structure and, in particular, of the current density in the cross-section of the planar conductive track structure, gaps are provided in a targeted manner in the ferromagnetic core. The gaps in the ferromagnetic core are arranged in regions above and/or below the planar conductive track structure.

Claims

1. An inductive component (1), having: a planar printed conductor structure (10) which comprises an upper side (11), and an underside (12), wherein the upper side (11) is arranged opposite the underside (12), and a ferromagnetic core (20), which is arranged around the planar printed conductor structure (10), wherein the ferromagnetic core (20) incorporates a plurality of gaps (21) in a region (A) of the upper side (11) and/or underside (12) of the planar printed conductor structure (10), and wherein each of the plurality of gaps (21) is filled with a different dielectric fill material.

2. The inductive component (1) as claimed in claim 1, wherein the planar printed conductor structure (10) comprises a plurality of parallel-oriented printed conductors (10-i).

3. The inductive component (1) as claimed in claim 1, wherein the planar printed conductor structure (10) comprises a plurality of printed conductors (10-i) arranged one on top of another.

4. The inductive component (1) as claimed in claim 1, wherein the planar printed conductor structure (10) comprises a plurality of coplanar printed conductors (10-i), and wherein at least one gap of the plurality of gaps (21) is arranged in the region (A) of the upper side (11) and/or underside (12) of each printed conductor (10-i).

5. The inductive component (1) as claimed in claim 1, wherein the magnetic core (20), in the region of the upper side (11) and/or underside (12) of the planar printed conductor structure (10), incorporates a material with ferromagnetic powder particles.

6. The inductive component (1) as claimed in claim 1, having a carrier substrate (30), wherein the underside (11) and/or upper side (12) of the planar printed conductor structure (10) is arranged on the carrier substrate (30).

7. A high-frequency filter device having an inductive component (1) as claimed in claim 1.

8. The inductive component (1) as claimed in claim 1, wherein the different dielectric fill materials are configured to, when filled into respective gaps of the plurality of gaps (21), influence magnetic flux across the planar printed conductor structure (10) to achieve a more uniform current distribution.

9. The inductive component (1) as claimed in claim 1, wherein the ferromagnetic core (20) incorporates a first plurality of the plurality of gaps (21) in a region of the upper side (11) of the planar printed conductor structure (10) and a second plurality of the plurality of gaps (21) in a region of the underside (12) of the planar printed conductor structure (10).

10. An inductive component (1), having: a planar printed conductor structure (10) which comprises an upper side (11), and an underside (12), wherein the upper side (11) is arranged opposite the underside (12), and a ferromagnetic core (20), which is arranged around the planar printed conductor structure (10), wherein the ferromagnetic core (20) incorporates a first plurality of gaps (21) in a region of the upper side (11) of the planar printed conductor structure (10) and a second plurality of gaps (21) in a region of the underside (12) of the planar printed conductor structure (10), and wherein each of the first plurality of gaps (21) or each of the second plurality of gaps (21) is filled with a different dielectric fill material.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The present invention is described in greater detail hereinafter with reference to the forms of embodiment represented in the schematic figures of the drawings. In the drawings:

(2) FIG. 1: shows a schematic representation of a cross-section of an inductive component according to one form of embodiment;

(3) FIG. 2: shows a schematic representation of a cross-section of an inductive component according to a further form of embodiment;

(4) FIG. 3: shows a schematic representation of a cross-section of an inductive component according to one further form of embodiment;

(5) FIG. 4: shows a schematic representation of a cross-section of a subregion of an inductive component according to one form of embodiment;

(6) FIGS. 5a, 5b: show a perspective representation of an inductive component according to a further form of embodiment; and

(7) FIG. 6: shows a schematic representation of a cross-section of a conventional component.

DETAILED DESCRIPTION

(8) In the following description, identical or similar components are identified by the same reference symbols. Moreover, the forms of embodiment described hereinafter, insofar as this is rational, can be mutually combined in an arbitrary manner.

(9) FIG. 6 shows a cross-section of an arrangement for an inductive component. An electrically conductive printed conductor structure 110 is fitted to a carrier substrate 130. This can involve, for example, a printed conductor on a circuit board substrate. The height h of the printed conductor structure 110 is significantly smaller than the width b of the printed conductor structure 110. The printed conductor structure 110 is enclosed by two half-shells 120, which are intended to constitute a magnetic core. On the grounds of the continuity of the carrier substrate 130, the core constituted by the two half-shells 120 is interrupted at the positions 121. Consequently, at the positions 121, the magnetic core respectively incorporates a gap, which increases the magnetic field strength in this region.

(10) In an arrangement represented according to FIG. 6, the orientation of the magnetic field lines associated with the position of the gap 121 in the magnetic core results in a current displacement in the printed conductor 110 towards the edges of the printed conductor structure 110.

(11) If, moreover, a high-frequency electric current is fed through the electrical conductor 110, the current flux is likewise displaced into the edge regions of the electrical conductor 110. The maximum current-carrying capacity is significantly reduced as a result.

(12) FIG. 1 shows a schematic representation of a cross-section of an inductive component 1 according to one form of embodiment. The inductive component 1 comprises a planar printed conductor structure 10 and a ferromagnetic core 20. The cross-section of the planar printed conductor structure 10 assumes a height h which is significantly smaller than the width b of the planar printed conductor structure. The width b lies in the direction of the transverse extension of the planar printed conductor structure 10. In particular, the width b can be greater than the height h by more than one order of magnitude, i.e. by a factor of 10. Along a predefined section in the direction of the longitudinal extension of the printed conductor structure 10, said planar printed conductor structure 10 is enclosed by a ferromagnetic core 20. The ferromagnetic core 20 can be constituted of any ferromagnetic material.

(13) In particular, the planar printed conductor structure 10 comprises an upper side 11 and an underside 12 which is arranged opposite the upper side 11. The upper side 11 and the underside 12 are those sides which assume the larger dimensions, in this case, consequently, the width b, which is significantly greater than the height h. The printed conductor structure 10 can be constituted, for example, of any electrically conductive material, e.g. of copper. For example, the planar printed conductor structure 10 can be configured as a printed conductor structure of a printed circuit. Moreover, however, any other planar printed conductor structures are possible.

(14) The ferromagnetic core 20, which encloses the planar printed conductor structure 10 in a predefined section, incorporates at least one gap 21. The gap or gaps 21 are arranged in a region A of the upper side 11 and/or the underside 12. By this, it is to be understood that, for example, a virtual and notional line V, which is perpendicular to the upper side 11 or the underside 12, runs through the corresponding gap 21. For example, in FIG. 1, a virtual line of this type is represented as a broken line V.

(15) Conversely to FIG. 6, the inductive component 1 expressly incorporates no gap in region B of the lateral faces, i.e. in the region of those faces which interconnect the upper side 11 and the underside 12.

(16) As a result of the gaps 21 in region A of the upper side 11 or the underside 12 of the planar printed conductor structure 10, inconsistencies occur in the magnetic field characteristic, which can influence the current flux through the planar printed conductor structure 10. In particular, as a result of these inconsistencies in the magnetic field, the current flux is at least partially displaced away from the edge towards the center of the planar printed conductor structure 10. Particularly in the case of high-frequency signals, this counteracts any skin effect, as a result of which the electric current flux would be displaced towards the outer surface. Accordingly, by the targeted positioning and arrangement of gaps 21 in the ferromagnetic core 20, an electric current flux can be achieved in the planar printed conductor structure 10 which also encompasses the inner region of said planar printed conductor structure 10. In particular, the electric current flux can be displaced away from the edge region into the inner region of the planar printed conductor structure 10. In this manner, the current-carrying capacity of the planar printed conductor structure 10 can be increased.

(17) Optionally, the gap 21 in the ferromagnetic core 20 can be filled with a dielectric filler material 22. By the selection of an appropriate dielectric filler material 22, an influence can also be exerted upon the magnetic field line characteristic, and thus upon current distribution within the planar printed conductor structure 10. Where a plurality of gaps 21 are present in the ferromagnetic core 20, the individual gaps 21 can either be filled with the same filler material 22 or, optionally, different dielectric filler materials 22 can also be employed for the individual gaps 21.

(18) Moreover, the edges of the ferromagnetic core 20 can be rounded in the region of the transition to the gaps 21.

(19) FIG. 2 shows a schematic representation of a cross-section of an inductive component 1 according to a further form of embodiment. The form of embodiment represented in FIG. 2 particularly differs from the above-mentioned form of embodiment in that, instead of a single gap 21 in region A of the upper side 11 or the underside 12 of the planar printed conductor structure 10, a plurality of gaps 21 are present in this case. However, the number of four gaps 21 represented here is an arbitrary example only. Moreover, any other arbitrary number of gaps 21 on the upper side and/or underside of the planar printed conductor structure 10 is also possible. It should also be observed that gaps 21, as represented here, can be incorporated both in the region of the upper side 11 and in the region of the underside 12. In principle, however, it is also possible for gaps 21 to be provided only in the region of the upper side 11 or, alternatively, only in the region of the underside 12.

(20) FIG. 3 shows a schematic representation of a cross-section of an inductive component 1 according to one further form of embodiment. The exemplary embodiment represented here particularly differs from the above-mentioned exemplary embodiment, in that the planar printed conductor structure 10 is arranged on an electrically insulating carrier substrate 30. In particular, one side of the planar printed conductor structure 10, in this case particularly the underside 12 of the planar printed conductor structure 10, is connected to one side of the carrier substrate 30.

(21) In addition to the form of embodiment of a planar printed conductor structure 10 represented here, moreover, arrangements having a plurality of printed conductors are also possible. For example, planar printed conductors can be arranged respectively on two opposing sides of the carrier substrate 30. Moreover, for example, a laminated structure comprised of a plurality of carrier substrates 30 and, optionally, a plurality of planar printed conductors is also possible. Optionally, a plurality of printed conductors can also be arranged next to one another on the carrier substrate 30 to constitute a planar printed conductor structure 10.

(22) FIG. 4 shows a schematic representation of part of an inductive component 1 according to a further form of embodiment. As can be seen in the exemplary embodiment represented here, the planar printed conductor structure 10 can comprise a plurality of individual printed conductors 10-i. These individual printed conductors 10-i, for example, can be arranged one on top of another. In this context, the term one on top of another signifies, for example, that the underside of a printed conductor 10-1 in each case faces an upper side of an adjoining printed conductor 10-1. Moreover, the individual printed conductors 10-i in the printed conductor structure 10 can also assume different dimensions. For example, the upper two printed conductors 10-1 and 10-2 have a smaller width than the printed conductors 10-3 and 10-4 which are arranged thereunder. Additionally, it is also possible for a plurality of printed conductors 10-i to be arranged next to one another in a common plane. In this manner, for example, a coplanar printed conductor arrangement 10 can be achieved.

(23) As can moreover be seen from the example according to FIG. 4, the width d1, d2 of the gaps 21 can vary. For example, the width d1, d2 of the gaps 21 can be adapted in accordance with the respective printed conductor structure 10. Thus, for example, in the event of a higher number of printed conductors 10-i, or of printed conductors 10-i in which a higher current density is anticipated, a greater gap width d1 can be selected, whereas, in the event of a lower number of printed conductors 10-i, or where the anticipated current density is lower, a smaller gap width d2 can be set. Moreover, for example, the number of gaps 21, in accordance with the configuration of the printed conductor structure 10, can also be varied over the width thereof. In this manner, in accordance with the properties of the planar printed conductor structure 10, the density of gaps 21 in the ferromagnetic core 20 can be varied.

(24) FIGS. 5a and 5b show a perspective representation of an inductive component 1 according to one form of embodiment. The planar printed conductor structure 10 is represented in the partial illustration 5a. The planar printed conductor structure 10 comprises a plurality of turns. In the partial illustration 5b, it is further represented how the planar printed conductor structure 10 can be enclosed by a ferromagnetic core 20. This ferromagnetic core 20 can, for example, according to the profile of the planar printed conductor structure 10, incorporate one or more gaps 21. In this manner, the current flux characteristic within the planar printed conductor structure 10 can be deliberately influenced. Consequently, in accordance with the annular profile of the printed conductor structure 10 in the present exemplary embodiment, the gap 21 in the ferromagnetic core 20 also assumes an annular configuration.

(25) The above-mentioned inductive component 1 can be employed, for example, as an inductive filter component for a high-frequency filter device. Optionally, to this end, the above-mentioned inductive component 1 can be combined with further components such as, for example, an ohmic resistor and/or a capacitive component.

(26) In summary, the present invention relates to an inductive component having a planar printed conductor structure. The planar printed conductor structure is enclosed by a ferromagnetic core along a predefined section. For the targeted control of the current flux within the planar printed conductor structure, and particularly of the current density in a cross-section of the planar printed conductor structure, gaps are deliberately provided in the ferromagnetic core. Gaps in the ferromagnetic core are arranged in regions above and/or below the planar printed conductor structure.