Composite inductor and DC-DC converter using the same

Abstract

To provide a composite inductor improved in inductance while suppressing a binding between coil conductors, and provide a DC-DC converter using the same.SOLUTION: In a composite inductor, when a voltage is applied via each terminal part 23, a current flows through each of a first coil conductor 20A and a second coil conductor 20B. At this time, a coupling may occur between the first coil conductor 20A and the second coil conductor 20B. However, a first magnetic material 30A is provided, so that the coupling between the first coil conductor 20A and the second coil conductor 20B is suppressed. Further, a pair of second magnetic materials 30B is additionally provided, so that a high inductance can be realized.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present disclosure relates to a composite inductor and a DC-DC converter using the same.

Background Art

[0002] Patent Document 1 below discloses an inductor having a configuration in which a plurality of magnetic cores provided with coil conductors inside and a plurality of shield portions having a higher magnetic permeability than the magnetic cores are arranged side by side, and a composite inductor including a plurality of coil conductors in a single component. In the composite inductor in this document, the coupling between the coil conductors of both magnetic cores is suppressed by the shield portion interposed between two adjacent magnetic cores.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] As a result of intensive research, the inventors have newly found a technique capable of improving the inductance while suppressing the coupling between coil conductors in a composite inductor.

[0005] An object of the present disclosure is to provide a composite inductor in which the inductance is improved while suppressing the coupling between coil conductors, and a DC-DC converter using the same.

Means for Solving the Problems

[0006] A composite inductor according to one embodiment of the present disclosure has a rectangular parallelepiped shape and a first element having a pair of first sides facing each other in a first direction, a pair of second sides facing each other in a second direction perpendicular to the first direction, and a pair of third sides facing each other in a third direction perpendicular to both the first and second directions, and is made of a material including a magnetic material; a first coil conductor provided within the element and comprising a first conductor extending along a first direction, a second conductor extending along a first direction and adjacent to the first conductor in a second direction, and a third conductor extending along a second direction and connecting one end of the first conductor and the second conductor in the first direction; a second coil conductor provided within the element and aligned with the first coil conductor in a third direction, comprising a first conductor, a second conductor and a third conductor; and a component provided within the element and having a rectangular parallelepiped shape, The first magnetic material is interposed between the first coil conductor and the second coil conductor in the third direction and has a pair of fourth sides facing each other in the first direction, a pair of fifth sides facing each other in the second direction, and a pair of sixth sides facing each other in the third direction, and has a higher permeability than the first elemental body. The second magnetic material is provided inside the elemental body, has a rectangular parallelepiped shape, and is provided in a region different from the region where the first magnetic material is provided in a cross section perpendicular to the first direction, and has a pair of seventh sides facing each other in the first direction, a pair of eighth sides facing each other in the second direction, and a pair of ninth sides facing each other in the third direction, and has a higher permeability than the first elemental body. In a cross section perpendicular to the first direction, the first elemental body is located at least outside the first conductor and the second conductor in the second direction of the first coil conductor and the second coil conductor, respectively. [Effects of the Invention]

[0007] According to this disclosure, it is possible to provide a composite inductor that improves inductance while suppressing coupling between coil conductors, and a DC-DC converter using the same. [Brief explanation of the drawing]

[0008] [Figure 1] This is a schematic perspective view showing a composite inductor according to one embodiment. [Figure 2] This is a view of the composite inductor shown in Figure 1, seen from the end face. [Figure 3] Figure 1 is an exploded perspective view showing the coil conductor and magnetic material of a composite inductor. [Figure 4] Figure 3 is a schematic perspective view showing the coil conductor. [Figure 5] Figure 3 is a front view showing the coil conductor. [Figure 6] This figure shows the structure of the magnetic material in Figure 1. [Figure 7] This diagram shows magnetic materials in different forms. [Figure 8] Figure 1 is a cross-sectional view of the composite inductor along line VIII-VIII. [Figure 9] This diagram shows composite inductors of different configurations. [Figure 10] This diagram shows composite inductors of different configurations. [Figure 11] This diagram shows composite inductors of different configurations. [Figure 12] Figure 11 is a cross-sectional view of the composite inductor along line XII-XII. [Figure 13] This diagram shows composite inductors of different configurations. [Figure 14] Figure 1 shows the circuit diagram of a DC-DC converter that uses the composite inductor shown in Figure 1. [Modes for carrying out the invention]

[0009] Embodiments of this disclosure will be described in detail below with reference to the attached drawings. In this description, the same reference numerals will be used for elements that are the same or have the same function, and redundant explanations will be omitted.

[0010] Figures 1 to 3 show an inductor 1 according to one embodiment. The inductor 1 is composed of a base body 10, a pair of coil conductors 20, and three magnetic materials 30. In other words, the inductor 1 according to this embodiment is a composite inductor provided with two inductors.

[0011] The pair of coil conductors 20 (20A and 20B) included in inductor 1 can be used as choke coils in the DC-DC converter 5 circuit shown in Figure 14. DC-DC converter 5 is a multi-phase converter in which a pair of conversion sections consisting of switching elements SW1 and SW2, choke coils 20A and 20B, and diodes D1 and D2 are connected in parallel, and the above-mentioned inductor 1 can be used as the choke coils 20A and 20B in each conversion section. To describe the configuration of DC-DC converter 5 in more detail, DC-DC converter 5 includes a pair of input terminals A1 and A2, a pair of output terminals B1 and B2, a switching element SW1 and choke coil 20A connected in series between input terminal A1 and output terminal B1 in that order, a switching element SW2 and choke coil 20B connected in series between input terminal A1 and output terminal B1 in that order, and a capacitor C1 connected between output terminals B1 and B2. A circuit consisting of switching element SW1 and choke coil 20A, and a circuit consisting of switching element SW2 and choke coil 20B are connected in parallel between input terminal A1 and output terminal B1. Input terminal A2 and output terminal B2 form a ground line. Diode D1 is connected in reverse between the connection point of switching element SW1 and choke coil 20A and the ground line, and diode D2 is connected in reverse between the connection point of switching element SW2 and choke coil 20B and the ground line. Switching elements SW1 and SW2 are alternately turned on and off by a control circuit (not shown), thereby generating an output voltage obtained by stepping down the input voltage. By configuring the pair of choke coils 20A and 20B in the DC-DC converter 5 with a pair of coil conductors 20 of inductor 1, the number of components constituting the DC-DC converter 5 can be reduced.

[0012] The base body 10 has an outer shape of a substantially rectangular parallelepiped shape. The base body 10 has an upper surface 10a and a lower surface 10b (a pair of first side surfaces) facing each other in the vertical direction which is the first direction, a pair of side surfaces 10e, 10f (a pair of second side surfaces) facing each other in the second direction orthogonal to the first direction, and a pair of end surfaces 10c, 10d (a pair of third side surfaces) facing each other in the third direction orthogonal to the first and second directions. The base body 10 according to the present embodiment is configured to include a first base body portion 11, a second base body portion 12, and a third base body portion 13. The first base body portion 11 constitutes the upper surface 10a of the base body 10, the third base body portion 13 constitutes the lower surface 10b of the base body 10, and the second base body portion 12 is interposed between the first base body portion 11 and the third base body portion 13 in the vertical direction of the base body 10.

[0013] A pair of coil conductors 20 and three magnetic bodies 30 are provided in the base body 10. The pair of coil conductors 20 are arranged along the facing direction of the end surfaces 10c, 10d of the base body 10, and the magnetic bodies 30 are disposed between and outside the pair of coil conductors 20 respectively. In the following description, as necessary, among the pair of coil conductors 20, the coil conductor 20 located on the end surface 10c side is referred to as the first coil conductor 20A, and the coil conductor 20 located on the end surface 10d side is referred to as the second coil conductor 20B. Also, as necessary, among the three magnetic bodies 30, the magnetic body 30 interposed between the pair of coil conductors 20 is referred to as the first magnetic body 30A, and the magnetic body 30 located outside the pair of coil conductors 20 is referred to as the second magnetic body 30B.

[0014] As shown in FIGS. 3 and 4, each of the pair of coil conductors 20 has a configuration in which a single elongated strip conductor is substantially rectangular wave-shaped. Each coil conductor 20 can be formed, for example, by bending a single elongated strip conductor. More specifically, each coil conductor 20 includes a pair of parallel portions 21, a connecting portion 22, and a pair of terminal portions 23. Each coil conductor 20 is made of a metal selected from Cu, Ag, Au, Al, Ni, etc., and is made of Cu in the present embodiment. The surface of each coil conductor 20 may be covered by an insulating coating not shown, for example, each of the parallel portions 21 and the connecting portion 22 may be covered by an insulating coating.

[0015] The pair of parallel portions 21 is composed of a first parallel portion 21A (first conductor) and a second parallel portion 21B (second conductor). The first parallel portion 21A and the second parallel portion 21B have the same length and extend parallel to each other. In the state where the coil conductor 20 is attached to the base body 10 as shown in FIG. 2, the pair of parallel portions 21 extends in the thickness direction of the base body 10 (that is, the first direction in which the upper surface 10a and the lower surface 10b face each other). Hereinafter, the extending direction of the parallel portion 21 is also referred to as the first direction. Both the first parallel portion 21A and the second parallel portion 21B have upper end portions 21a located on the upper surface 10a side, and the upper end portions 21a are arranged side by side in the facing direction of the pair of side surfaces 10e, 10f. Similarly, both the first parallel portion 21A and the second parallel portion 21B have lower end portions 21b located on the lower surface 10b side, and the lower end portions 21b are arranged side by side in the facing direction of the pair of side surfaces 10e, 10f. As shown in FIG. 4, both of the pair of parallel portions 21 have a rectangular cross-section in a cross-section orthogonal to their extending direction, have side surfaces 21c, 21d parallel to the end surfaces 10c, 10d of the base body 10, and have outer side surfaces 21e and inner side surfaces 21f parallel to the side surfaces 10e, 10f of the base body 10. The side surface 21c of the parallel portion 21 faces the end surface 10c side of the base body 10, and the side surface 21d faces the end surface 10d side of the base body 10. The outer side surface 21e of the parallel portion 21 faces outward, and the inner side surfaces 21f face inward and face each other.

[0016] The connecting portion 22 (third conductor) is the part that connects the upper ends 21a of each of the pair of parallel portions 21, and extends in a straight line in the direction opposite to the pair of side surfaces 10e and 10f of the base body 10. Hereinafter, the direction in which the connecting portion 22 extends will also be referred to as the second direction. As shown in Figure 4, the connecting portion 22 has a rectangular cross-section in a cross-section perpendicular to its direction of extension, and has upper and lower surfaces 22a and 22b that are parallel to the upper and lower surfaces 10a and 10b of the base body 10, as well as side surfaces 22c and 22d that are parallel to the end surfaces 10c and 10d of the base body 10. Side surface 22c of the connecting portion 22 faces the end surface 10c side of the base body 10, and side surface 22d faces the end surface 10d side of the base body 10. The connection point 26 (see Figure 2) between the parallel portion 21 and the connecting portion 22 is curved at a right angle, and its outer and inner surfaces constitute curved surfaces.

[0017] The pair of terminal portions 23 (fourth conductors) are both ends of the coil conductor 20 and extend away from each other from the respective lower ends 21b of the pair of parallel portions 21. As shown in Figure 2, when the coil conductor 20 is attached to the base body 10, the pair of terminal portions 23 are exposed on the lower surface 10b of the base body 10 and extend along the opposing directions of the sides 10e and 10f. Specifically, the first terminal portion 23A of the pair of terminal portions 23 extends toward the side 10e, and the second terminal portion 23B extends toward the side 10f. As shown in Figure 4, each of the pair of terminal portions 23 has a rectangular cross-section in a cross-section perpendicular to its extending direction, and has upper and lower surfaces 23a and 23b that are parallel to the upper and lower surfaces 10a and 10b of the base body 10, as well as sides 23c and 23d that are parallel to the end faces 10c and 10d of the base body 10. The side surface 23c of the terminal portion 23 faces the end surface 10c of the base body 10, and the side surface 23d faces the end surface 10d of the base body 10. In this embodiment, as shown in Figure 5, the height h1 (i.e., length in the first direction) of each terminal portion 23 is designed to be shorter than the width W1 (i.e., length in the second direction) of each parallel portion 21. The pair of terminal portions 23 function as terminals of the inductor 1 and can be electrically connected to terminals on the circuit board side to which the inductor 1 is surface mounted. In this embodiment, the pair of terminal portions 23 are terminated on the lower surface 10b, but may be extended along the sides 10e and 10f as needed. Alternatively, the pair of terminal portions 23 may extend along the opposing directions of the sides 10e and 10f so as to be close to each other without contact. The coil conductor 20 may not have a pair of terminal portions 23, in which case it can be mounted at the lower end 21b of the pair of parallel portions 21.

[0018] Each magnetic body 30 has a rectangular plate-like outer shape and extends parallel to a plane including the first and second directions. The first magnetic body 30A has an upper surface 30a and a lower surface 30b (a pair of fourth sides) facing each other in the first direction, a pair of sides 30e and 30f (a pair of fifth sides) facing each other in the second direction, and a pair of end faces 30c and 30d (a pair of sixth sides) facing each other in the third direction. The second magnetic body 30B has an upper surface 30a and a lower surface 30b (a pair of seventh sides) facing each other in the first direction, a pair of sides 30e and 30f (a pair of eighth sides) facing each other in the second direction, and a pair of end faces 30c and 30d (a pair of ninth sides) facing each other in the third direction. The upper surface 30a and the lower surface 30b of each magnetic body 30 are parallel to the upper surface 10a and the lower surface 10b of the base body 10, respectively. The end faces 30c and 30d of each magnetic material 30 are parallel to the end faces 10c and 10d of the base body 10, respectively. The side faces 30e and 30f of each magnetic material 30 are parallel to the side faces 10e and 10f of the base body 10, respectively. As shown in Figure 2, the upper surface 30a of each magnetic material 30 is located below the upper surface 22a of the connecting portion 22 of each coil conductor 20. The lower surface 30b of each magnetic material 30 is not exposed to the lower surface 10b of the base body 10, and a third base body portion 13 is interposed between the magnetic material 30 and the lower surface 10b of the base body in the vertical direction. The height position of the upper surface 30a of each magnetic material 30 may be below the height position of the lower surface 22b of the connecting portion 22 of each coil conductor 20, or it may be between the height position of the upper surface 22a and the height position of the lower surface 22b of the connecting portion 22 of each coil conductor 20.

[0019] Each magnetic material 30 can be configured to have a relatively high magnetic permeability, and can be designed to have a higher magnetic permeability than the magnetic powder-containing resin constituting the second and third base body parts 12 and 13, which will be described later. As shown in Figure 6, each magnetic material 30 according to this embodiment includes a plurality of magnetic strips 32 (more specifically, strips made of metallic soft magnetic material) stacked in the vertical direction (i.e., first direction) of the base body 10, and has a laminated structure in which the plurality of magnetic strips 32 and the plurality of adhesive layers 34 are arranged alternately. The upper surface 30a and lower surface 30b of each magnetic material 30 may be composed of magnetic strips 32 or adhesive layers 34. The number of layers of magnetic strips 32 constituting each magnetic material 30 is, as an example, 120 layers. The magnetic strips 32 may be composed of, for example, amorphous alloys, microcrystalline alloys, permalloys, alloys made of nanoheterostructures, and other magnetic alloys. Amorphous alloy materials include Fe-based amorphous soft magnetic materials and Co-based amorphous soft magnetic materials, while microcrystalline alloys include Fe-based nanocrystalline soft magnetic materials. A nanoheterostructure refers to a structure in which microcrystals exist within an amorphous material. The surface of each magnetic material 30 may be covered with an insulating coating (not shown) as needed.

[0020] Since the magnetic material 30 according to this embodiment is composed of multiple magnetic strips 32, the end faces 30c, 30d and side faces 30e, 30f are not easily smooth, and a certain degree of unevenness is present along the entire length in the vertical direction. This uneven surface is in contact with the second base body portion 12. As a result, the end faces 30c, 30d and side faces 30e, 30f of the magnetic material 30 are rougher than the upper and lower surfaces 30a, 30b. This rough surface improves the adhesion between the magnetic material 30 and the base body 10 in contact with it.

[0021] Each magnetic material 30 may be composed of multiple blocks (magnetic material blocks). For example, as shown in Figure 7, the magnetic material 30 may be composed of two magnetic material blocks 30M and 30N that overlap in the vertical direction. Each magnetic material block 30M and 30N has a laminated structure in which multiple magnetic thin strips 32 and multiple adhesive layers 34 are arranged alternately, as shown in Figure 6. The magnetic material block 30M and the magnetic material block 30N are bonded together by an adhesive layer 36. The constituent material of the adhesive layer 36 may be the same as or different from the constituent material of the adhesive layer 34 contained in each magnetic material block 30M and 30N. Each magnetic material 30 is not limited to a laminated structure, but may also have a single-layer structure, for example, a single-layer ferrite block.

[0022] Next, we will explain in more detail the arrangement of each coil conductor 20 and each magnetic material 30 provided within the base body 10.

[0023] As shown in Figures 1 and 2, the base body 10 has a configuration in which a first base body part 11, a second base body part 12, and a third base body part 13 are arranged from top to bottom. The first base body part 11 (second base body part) is made of a non-magnetic resin, for example, a liquid crystal polymer. The second base body part 12 (first base body part) and the third base body part 13 (third base body part) are both made of a material containing a magnetic material, for example, a magnetic powder-containing resin (specifically, a thermosetting resin containing soft magnetic metal powder). The soft magnetic metal powder can be, for example, iron, iron-silicon alloy, permalloy, sendust, amorphous, or microcrystalline alloy powders, and these may be combined. The thermosetting resin can be, for example, epoxy resin. The constituent materials of the second base body part 12 and the constituent materials of the third base body part 13 may be the same or different. Furthermore, the first elemental part 11 may contain a magnetic material, and may be made of the same material as the constituent material of the second elemental part 12 and the constituent material of the third elemental part 13.

[0024] The first base portion 11 constitutes the upper surface 10a of the base portion 10 and has a substantially flat outer shape that extends parallel to the upper surface 10a. The third base portion 13 constitutes the lower surface 10b of the base portion 10 and has a substantially flat outer shape that extends parallel to the lower surface 10b. The second base portion 12 is sandwiched between the first base portion 11 and the third base portion 13 in the vertical direction and extends parallel to the upper and lower surfaces 10a and 10b of the base portion 10. As shown in the cross-sectional view in Figure 8, the second base portion 12 has, more specifically, five regions S1 to S5. Of the five regions, the first region S1 is the region between the first parallel section 21A and the second parallel section 21B in the second direction, the second region S2 is the region between the parallel section 21 and the sides 10e and 10f in the second direction, the third region S3 is the region between the first magnetic material 30A and the sides 10e and 10f in the second direction, the fourth region S4 is the region between the second magnetic material 30B and the sides 10e and 10f in the second direction, and the fifth region S5 is the region on the end faces 10c and 10d side of the second magnetic material 30B.

[0025] Each first region S1 is in contact with the inner surfaces 21f of the parallel sections 21A and 21B of the coil conductor 20, and also in contact with the end faces 30c and 30d of the first magnetic material 30A and the second magnetic material 30B. Each second region S2 is in contact with the outer surfaces 21e of the parallel sections 21A and 21B of the coil conductor 20, and also in contact with the end faces 30c and 30d of the magnetic material 30, and constitutes a part of the sides 10e and 10f of the base body 10. Each third region S3 is in contact with the sides 30e and 30f of the first magnetic material 30A, and constitutes a part of the sides 10e and 10f of the base body 10. Each fourth region S4 is in contact with the sides 30e and 30f of the second magnetic material 30B, and constitutes a part of the sides 10e and 10f of the base body 10. Each fifth region S5 is in contact with the end faces 30c and 30d of the second magnetic material 30B and constitutes a part of the end faces 10c and 10d of the element 10.

[0026] In this embodiment, in the cross-section shown in Figure 8, the first magnetic body 30A and the pair of second magnetic bodies 30B have the same cross-sectional shape and dimensions and extend along the second direction (left-right direction in Figure 8). With respect to the third direction (up-down direction in Figure 8), the first magnetic body 30A is in contact with the parallel portions 21 of the first coil conductor 20A and the second coil conductor 20B at its end faces 30c and 30d. The first magnetic body 30A may be in direct or indirect contact with the parallel portions 21. In the indirect contact configuration, an insulating coating provided on the surface of the first magnetic body 30A or the surface of the coil conductor 20 may be interposed between the first magnetic body 30A and the parallel portions 21 of the coil conductor 20, or the space between the first magnetic body 30A and the parallel portions 21 of the coil conductor 20 may be filled with a magnetic powder-containing resin. When the space between the first magnetic material 30A and the parallel portion 21 of the coil conductor 20 is filled with a magnetic powder-containing resin, the magnetic powder-containing resin may be the same as the material constituting the second base body portion 12. Similarly, with respect to the third direction, the second magnetic material 30B located on the end face 10c side of the base body 10 is in contact with the parallel portion 21 of the first coil conductor 20A at the end face 30d, and the second magnetic material 30B located on the end face 10d side of the base body 10 is in contact with the parallel portion 21 of the second coil conductor 20B at the end face 30c. Each second magnetic material 30B may be in direct or indirect contact with the parallel portion 21. In the indirect contact configuration, an insulating coating provided on the surface of the second magnetic material 30B or the surface of the coil conductor 20 may be interposed between the second magnetic material 30B and the parallel portion 21 of the coil conductor 20, and the space between the second magnetic material 30B and the parallel portion 21 of the coil conductor 20 may be filled with a magnetic powder-containing resin. When the space between the second magnetic material 30B and the parallel portion 21 of the coil conductor 20 is filled with a magnetic powder-containing resin, the magnetic powder-containing resin may be the same as the material constituting the second base body 12. In the cross-section shown in Figure 8, the first magnetic material 30A and each of the second magnetic materials 30B may have different cross-sectional shapes and dimensions.

[0027] As shown in FIG. 8, the side surfaces 30e and 30f of the magnetic body 30 protrude outside the parallel portions 21A and 21B of the coil conductors 20A and 20B, respectively, and are close to the side surfaces 10e and 10f of the base body 10. In the present embodiment, the side surfaces 30e and 30f of the magnetic body 30 protrude by a length L2 from the parallel portions 21A and 21B of the coil conductors 20A and 20B, respectively, and the length L1 of the third region S3 in the second direction is shorter than the length L2 (L1 < L2). Similarly, the length of the fourth region S4 in the second direction is also shorter than the length L2. Thereby, while increasing the inductance in the inductor 1, the leakage magnetic flux at the side surfaces 10e and 10f of the base body 10 can be suppressed.

[0028] As shown in FIGS. 1 and 2, the first base body portion 11 integrally covers the upper surfaces 22a of the connection portions 22 of the first coil conductor 20A and the second coil conductor 20B, the upper surfaces 30a of the respective magnetic bodies 30, and the upper surfaces of the portions of the second base body portion 12 in the second region S2, the third region S3, the fourth region S4, and the fifth region S5 from the upper surface 10a side of the base body 10. The vertical height position of the interface between the first base body portion 11 and the second base body portion 12 can be set appropriately. In the present embodiment, the interface between the first base body portion 11 and the second base body portion 12 is located between the upper surface 22a and the lower surface 22b of the connection portion 22, and the second base body portion 12 is interposed at least partially between the connection point 26 between the parallel portion 21 and the connection portion 22 and the first base body portion 11. In this case, the lower surface of the connection portion 22b is entirely covered with a magnetic powder-containing resin that constitutes the second base body portion 12. The third base body portion 13 integrally covers the lower surface 30b of the magnetic body 30 and the lower surfaces of the portions of the second base body portion 12 in the first region S1, the third region S3, the fourth region S4, and the fifth region S5 from the lower surface 10b side of the base body 10. The vertical height position of the interface between the second base body portion 12 and the third base body portion 13 can also be set appropriately.

[0029] In the second base body portion 12, the portion of the fifth region S5 can be formed of a non-magnetic resin instead of a magnetic material.

[0030] In the inductor 1 described above, when a voltage is applied through each terminal portion 23, current flows through the first coil conductor 20A and the second coil conductor 20B, and coupling may occur between the first coil conductor 20A and the second coil conductor 20B. However, since the inductor 1 is provided with a first magnetic material 30A, coupling between the first coil conductor 20A and the second coil conductor 20B is suppressed, and furthermore, since a pair of second magnetic materials 30B are additionally provided, a high inductance can be achieved.

[0031] The second magnetic material 30B is not limited to the above configuration, as long as it is in contact with each parallel portion 21 of each coil conductor 20.

[0032] For example, a pair of second magnetic bodies 30B can be positioned between a pair of parallel sections 21 of each coil conductor 20, as shown in Figure 9. In the cross-section shown in Figure 9, with respect to the third direction, the second magnetic body 30B located on the end face 10c side of the base body 10 is in contact with the first magnetic body 30A at the end face 30d, and the second magnetic body 30B located on the end face 10d side of the base body 10 is in contact with the first magnetic body 30A at the end face 30c. Each second magnetic body 30B may be in direct or indirect contact with the parallel section 21. In the indirect contact configuration, an insulating coating provided on the surface of the first magnetic body 30A or the surface of the second magnetic body 30B may be interposed between the magnetic bodies 30, and the space between the magnetic bodies 30 may be filled with a magnetic powder-containing resin. In the configuration shown in Figure 9, the first magnetic body 30A and the second magnetic body 30B may be connected to each other.

[0033] Furthermore, the pair of second magnetic materials 30B can also be in a form in which the second magnetic material 30B shown in Figure 8 and the second magnetic material 30B shown in Figure 9 are combined, as shown in Figure 10. That is, in the cross-section shown in Figure 10, with respect to the third direction, the second magnetic material 30B located on the end face 10c side of the base material 10 has the same cross-sectional shape as the first magnetic material 30A and includes a first portion 30B1 that contacts the parallel portion 21 of the first coil conductor 20A at the end face 30d, and a second portion 30B2 that is interposed between the pair of parallel portions 21 of the first coil conductor 20A and contacts the first magnetic material 30A at the end face 30d. Similarly, with respect to the third direction, the second magnetic body 30B located on the end face 10d side of the base body 10 has the same cross-sectional shape as the first magnetic body 30A and includes a first portion 30B1 that contacts the parallel portion 21 of the second coil conductor 20B at its end face 30c, and a second portion 30B2 that is interposed between a pair of parallel portions 21 of the second coil conductor 20B and contacts the first magnetic body 30A at its end face 30c. Each second magnetic body 30B may be in direct or indirect contact with the parallel portion 21. In the indirect contact configuration, an insulating coating provided on the surface of each coil conductor 20 or the surface of the second magnetic body 30B may be interposed, or it may be filled with a magnetic powder-containing resin. Furthermore, in the indirect contact configuration, an insulating coating provided on the surface of the first magnetic material 30A or the surface of the second magnetic material 30B may be interposed between the magnetic materials 30, and the space between the magnetic materials 30 may be filled with a magnetic powder-containing resin. In the configuration shown in Figure 10, the first magnetic material 30A and the second magnetic material 30B may be connected to each other. Also, the first part 30B1 and the second part 30B2 of the second magnetic material 30B may be composed of connected magnetic materials, or they may be composed of separated magnetic materials.

[0034] The form of each coil conductor 20 is not limited to the above form and can be modified in various ways. For example, as shown in Figure 11, the connecting portion 22 of each coil conductor 20 may be bent from the parallel portion 21 toward the third direction outward. The length W2 (width) of each connecting portion 22 toward the third direction can be made longer than the length W1 (width) of each parallel portion 21 toward the second direction, thereby further reducing the electrical resistance of the coil conductor 20. The length h2 (height) of each connecting portion 22 toward the first direction can be designed to be lower than the height of the connecting portion 22 in the form in which the connecting portion 22 is not bent, as shown in Figure 4, etc., in which case the height of the coil conductor 20 and the inductor 1 can be reduced. Also, as shown in Figure 12, in a cross section perpendicular to the first direction, the length W1 of each parallel portion 21 toward the second direction can be designed to be longer than the length t (thickness) toward the third direction. In this case, the area of ​​the opposing surface of the coil conductor 20 facing the first magnetic material 30A increases, and a high inductance can be obtained. Furthermore, in a cross-section perpendicular to the first direction, the length L3 of the second region S2 of the second body portion 12 of the body 10 with respect to the third direction can be designed to be longer than the length t of each parallel portion 21 with respect to the third direction. In this case, the amount of magnetic powder-containing resin constituting the second body portion 12 can be increased, thereby achieving a higher inductance. In addition, interference and contact between each coil conductor 20 and the first magnetic material 30A during assembly can be significantly avoided, thereby preventing damage to the components constituting the inductor 1.

[0035] As shown in Figure 13, the pair of terminal portions 23 can be designed to be partially embedded in the third body portion 13 of the base body 10. In the embodiment shown in Figure 13, the upper end portion 23h of each terminal portion 23 is embedded in the third body portion 13 of the base body 10, while the lower end portion 23i of each terminal portion 23 is exposed from the third body portion 13. By having a structure in which a part of the terminal portion 23 is embedded in the base body 10 in this way, the terminal strength can be increased and the mountability can be improved.

[0036] The technology relating to this disclosure includes, but is not limited to, the following configuration examples.

[0037] A composite inductor according to one embodiment of the present disclosure has a rectangular parallelepiped shape and a first element having a pair of first sides facing each other in a first direction, a pair of second sides facing each other in a second direction perpendicular to the first direction, and a pair of third sides facing each other in a third direction perpendicular to both the first and second directions, and is made of a material including a magnetic material; a first coil conductor provided within the element and comprising a first conductor extending along a first direction, a second conductor extending along a first direction and adjacent to the first conductor in a second direction, and a third conductor extending along a second direction and connecting one end of the first conductor and the second conductor in the first direction; a second coil conductor provided within the element and aligned with the first coil conductor in a third direction, comprising a first conductor, a second conductor and a third conductor; and a component provided within the element and having a rectangular parallelepiped shape, The first magnetic material is interposed between the first coil conductor and the second coil conductor in the third direction and has a pair of fourth sides facing each other in the first direction, a pair of fifth sides facing each other in the second direction, and a pair of sixth sides facing each other in the third direction, and has a higher permeability than the first elemental body. The second magnetic material is provided inside the elemental body, has a rectangular parallelepiped shape, and is provided in a region different from the region where the first magnetic material is provided in a cross section perpendicular to the first direction, and has a pair of seventh sides facing each other in the first direction, a pair of eighth sides facing each other in the second direction, and a pair of ninth sides facing each other in the third direction, and has a higher permeability than the first elemental body. In a cross section perpendicular to the first direction, the first elemental body is located at least outside the first conductor and the second conductor in the second direction of the first coil conductor and the second coil conductor, respectively.

[0038] In the above-described composite inductor, when current flows through the first coil conductor and the second coil conductor, coupling may occur between the first and second coil conductors. In this inductor, since a pair of second magnetic materials are additionally provided in addition to the first magnetic material, it is possible to improve the inductance while suppressing coupling between the first and second coil conductors.

[0039] In other forms of composite inductors, in a cross-section perpendicular to the first direction, the pair of second magnetic materials are located outside the first and second conductors of the first and second coil conductors in the third direction, respectively, and extend along the second direction. In this case, precise alignment of the pair of second magnetic materials with respect to the first and second coil conductors is unnecessary, and the inductor can be easily manufactured.

[0040] In other forms of composite inductors, in a cross-section perpendicular to the first direction, a pair of second magnetic materials are positioned between the first and second conductors of the first and second coil conductors, respectively. In this case, since the length in the third direction is not extended even when a pair of second magnetic materials are placed, the component dimensions can be reduced.

[0041] In other forms of composite inductors, in a cross-section perpendicular to the first direction, a pair of second magnetic materials include a first portion that is located outside the first and second conductors of the first and second coil conductors in the third direction and extends along the second direction, and a second portion that is located between the first and second conductors of the first and second coil conductors, respectively, with the first and second portions connected. In this case, a large-capacity magnetic material can be placed inside the element, and coupling between the coil conductors can be suppressed to further improve the inductance.

[0042] In other forms of composite inductors, the fourth side of the pair of fourth sides of the first magnetic material located on one side in the first direction, and the seventh side of the pair of seventh sides of the second magnetic material located on one side in the first direction, are located on the other side in the first direction from the surface of the third conductor of the first coil conductor and the second coil conductor, respectively, in the first direction. In this case, the magnetic material becomes less susceptible to the influence of the magnetic field generated by the third conductor of the first coil conductor and the second coil conductor, resulting in a more uniform magnetic flux distribution within the magnetic material and improved saturation characteristics.

[0043] In other forms of composite inductors, the pair of fifth sides of the first magnetic material and the pair of eighth sides of the second magnetic material protrude outward from the first and second conductors of the first and second coil conductors, respectively, and are close to the pair of second sides of the elemental bodies. In this case, coupling between the coil conductors can be suppressed, thereby further improving the inductance.

[0044] In other forms of composite inductors, the first element of the element is located outside the first and second magnetic materials in the second direction, in a cross-section perpendicular to the first direction. In this case, the inductance can be increased while suppressing leakage flux on the sides of the element.

[0045] In other forms of composite inductors, the protrusion lengths of the pair of fifth sides of the first magnetic material and the pair of eighth sides of the second magnetic material from the first and second conductors of the first and second coil conductors, respectively, are longer than the length of the first elemental portion of the elemental body located outside the first and second magnetic materials in the second direction. In this case, leakage flux on the sides of the elemental body can be suppressed while increasing the inductance.

[0046] In other forms of composite inductors, in a cross-section perpendicular to the first direction, the length of the first elemental body portion located outside the first and second conductors in the second direction of the first and second coil conductors, respectively, with respect to the third direction, is longer than the length of the first and second conductors of the first and second coil conductors, respectively, with respect to the third direction. In this case, a higher inductance can be achieved by increasing the amount of magnetic powder-containing resin constituting the elemental body portion. In addition, interference and contact between the coil conductors and magnetic material during assembly can be significantly avoided, thereby preventing damage to the components constituting the composite inductor.

[0047] In other forms of composite inductors, in a cross-section perpendicular to the first direction, the first and second conductors of the first and second coil conductors, respectively, are in contact with the first magnetic material. In this case, the contact between the first magnetic material and the first and second coil conductors stabilizes their distance from each other, allowing for a stable inductance value to be obtained.

[0048] In other forms of composite inductors, in a cross-section perpendicular to the first direction, the first and second conductors of the first and second coil conductors are in contact with the second magnetic material. In this case, the contact between the second magnetic material and the first and second coil conductors stabilizes their distance from each other, allowing for a stable inductance value to be obtained.

[0049] In other forms of composite inductors, in a cross-section perpendicular to the first direction, the length of the first and second coil conductors, respectively, in the second direction is longer than the length in the third direction. In this case, the area of ​​the opposing surfaces of the coil conductors facing the first magnetic material with high magnetic permeability increases, and a high inductance can be obtained.

[0050] In other forms of composite inductors, the third conductors of the first and second coil conductors are bent outward in the third direction from the first and second conductors. In this case, the DC resistance of the current flowing through the coil conductors can be reduced while reducing the height dimension of the coil conductors.

[0051] In other forms of composite inductors, the length of the third conductor of the first and second coil conductors in the third direction is longer than the length of the first and second conductors of the first and second coil conductors in the second direction. In this case, the DC resistance of the current flowing through the coil conductors can be reduced while reducing the height dimension of the coil conductors.

[0052] In other forms of composite inductors, the first and second magnetic materials are constructed by laminating multiple magnetic ribbons, each composed of amorphous ribbons or nanocrystalline ribbons, in the first direction via an insulating layer. By using such materials with high magnetic permeability, the saturation magnetization is increased, enabling excellent DC superposition characteristics. Furthermore, since the magnetic fields generated in the first and second conductors of each coil conductor are generated in a plane perpendicular to the first direction, they are not affected by the reduction in magnetic permeability caused by the insulating layer. In addition, because the structure is via an insulating layer in the first direction, the generation of eddy current losses can be suppressed.

[0053] In other forms of composite inductors, the first and second magnetic materials include multiple magnetic material blocks in which multiple magnetic ribbons, each composed of amorphous ribbons or nanocrystalline ribbons, are stacked in a first direction via an insulating layer. Furthermore, multiple magnetic material blocks are stacked in the first direction. Using such high-permeability materials increases the saturation magnetization, enabling the realization of excellent DC superposition characteristics. Additionally, as the number of stacked magnetic materials increases, misalignment of the stacking positions becomes more likely; therefore, stacking in multiple blocks can reduce misalignment and improve dimensional accuracy.

[0054] In other forms of composite inductors, the pair of fifth and sixth sides of the first magnetic material and the pair of eighth and ninth sides of the second magnetic material are uneven surfaces, and these uneven surfaces are in contact with the first elemental body of the base material. The material constituting the first elemental body fills the unevenness, which fills the gaps that would otherwise reduce inductance, thereby obtaining high inductance, and also strengthening the adhesion between the base material and the first and second magnetic materials.

[0055] A composite inductor of another form further comprises a second element made of a resin-containing material, which integrally covers one side in the first direction of the third conductors of the first coil conductor and the third conductor of the second coil conductor, one side in the first direction of one of a pair of fourth sides of the first magnetic material and one side in the first direction of one of a pair of seventh sides of the second magnetic material and one side in the first direction of one of a pair of first sides of the first element part of the first element. In this case, the second element made of non-magnetic resin can reduce the magnetic flux component in the first direction generated in the third conductor, and the generation of eddy current losses due to the magnetic flux component in the first direction can be further reduced.

[0056] In other forms of composite inductors, the first element of the element is located outside the second magnetic material in the third direction, in a cross-section perpendicular to the first direction. In this case, the inductance can be increased while reducing the leakage flux at the end face of the element.

[0057] In other forms of composite inductors, the element further comprises a third element that integrally covers the fourth side of a pair of fourth sides of the first magnetic material located on the other side in the first direction, the seventh side of a pair of seventh sides of the second magnetic material located on the other side in the first direction, and the first side of a pair of first sides of the first element that is located on the other side in the first direction. In this case, the inductance can be increased while reducing the leakage flux on the lower surface of the element.

[0058] In other forms of composite inductors, the first coil conductor and the second coil conductor further include a fourth conductor that extends away from each other from the other end of the first conductor and the second conductor in the first direction, with one end of the fourth conductor in the first direction embedded in the third element and the other end of the fourth conductor in the first direction exposed from the third element. In this case, the strength of the fourth conductor, which can function as a terminal for the coil conductor, can be increased, improving mountability.

[0059] A DC-DC converter according to one embodiment of the present disclosure includes the above-mentioned composite inductor. This provides a DC-DC converter equipped with a composite inductor that improves inductance while suppressing coupling between coil conductors.

[0060] This disclosure is not limited to the embodiments described above, and various modifications are possible without departing from its essence. For example, the number of coil conductors included in the inductor may be three or more. Also, the number of magnetic materials included in the inductor may be four or more.

[0061] As can be understood from the above description, this specification discloses the following: [Note 1] A body having a rectangular parallelepiped shape, a pair of first sides facing each other in a first direction, a pair of second sides facing each other in a second direction perpendicular to the first direction, and a pair of third sides facing each other in a third direction perpendicular to both the first and second directions, and having a first body portion made of a material including a magnetic material, A first coil conductor provided within the element, comprising a first conductor extending along the first direction, a second conductor extending along the first direction and adjacent to the first conductor in the second direction, and a third conductor extending along the second direction and connecting one end of the first conductor and the second conductor in the first direction, A second coil conductor is provided within the aforementioned body, and is arranged in the third direction with respect to the first coil conductor, and comprises the first conductor, the second conductor, and the third conductor, A first magnetic material is provided within the element, has a rectangular parallelepiped shape, is interposed between the first coil conductor and the second coil conductor in the third direction, has a pair of fourth sides facing each other in the first direction, a pair of fifth sides facing each other in the second direction, and a pair of sixth sides facing each other in the third direction, and has a higher magnetic permeability than the first element. Provided within the aforementioned element, having a rectangular parallelepiped shape, and located in a region different from the region where the first magnetic material is provided in a cross-section perpendicular to the first direction, it comprises a pair of second magnetic materials having a pair of seventh sides facing each other in the first direction, a pair of eighth sides facing each other in the second direction, and a pair of ninth sides facing each other in the third direction, and having a higher magnetic permeability than the first element, A composite inductor in which, in a cross section perpendicular to the first direction, the first element portion of the element is located at least outside the first conductor and the second conductor in the second direction of the first coil conductor and the second coil conductor, respectively. [Note 2] The composite inductor according to Appendix 1, wherein in a cross section perpendicular to the first direction, the pair of second magnetic materials are located outside the first and second conductors of the first and second coil conductors in the third direction and extend along the second direction. [Note 3] The composite inductor according to Appendix 1, wherein in a cross section perpendicular to the first direction, the pair of second magnetic materials are positioned between the first conductor and the second conductor of the first coil conductor and the second coil conductor, respectively. [Note 4] In a cross-section perpendicular to the first direction, the pair of second magnetic materials include a first portion located outside the first and second conductors of the first and second coil conductors in the third direction and extending along the second direction, and a second portion located between the first and second conductors of the first and second coil conductors, respectively, wherein the first portion and the second portion are connected, as described in Appendix 1. [Note 5] The composite inductor according to any one of the appendices 1 to 4, wherein the fourth side of the pair of fourth sides of the first magnetic material located on one side in the first direction and the seventh side of the pair of seventh sides of the second magnetic material located on one side in the first direction are located on the other side in the first direction from the one side in the first direction of the third conductor of each of the first coil conductor and the second coil conductor. [Note 6] A composite inductor according to any one of the appendices 1 to 5, wherein the pair of fifth sides of the first magnetic material and the pair of eighth sides of the second magnetic material protrude outward from the first and second conductors of the first and second coil conductors, respectively, and are in close proximity to the pair of second sides of the element. [Note 7] A composite inductor according to any one of the appendices 1 to 6, wherein, in a cross-section perpendicular to the first direction, the first element portion of the element is also located outside the first magnetic material and the second magnetic material in the second direction. [Note 8] The composite inductor according to Appendix 7, wherein the protrusion lengths of the pair of fifth sides of the first magnetic material and the pair of eighth sides of the second magnetic material from the first conductor and the second conductor, respectively, of the first coil conductor and the second coil conductor are longer than the length of the first element portion of the element located outside the first magnetic material and the second magnetic material in the second direction. [Note 9] A composite inductor according to any one of the appendices 1 to 8, wherein, in a cross section perpendicular to the first direction, the length in the third direction of the first element portion of the element located outside the first conductor and the second conductor in the second direction of each of the first coil conductor and the second coil conductor is longer than the length in the third direction of each of the first conductor and the second conductor of the first coil conductor and the second coil conductor, respectively. [Note 10] A composite inductor according to any one of the appendices 1 to 9, wherein in a cross section perpendicular to the first direction, the first conductor and the second conductor of the first coil conductor and the second coil conductor, respectively, are in contact with the first magnetic material. [Note 11] In a cross-section perpendicular to the first direction, the first conductor and the second conductor of the first coil conductor and the second coil conductor, respectively, are in contact with the second magnetic material, as described in any one of the appendices 1 to 10. [Note 12] In a cross-section perpendicular to the first direction, the first conductor and the second conductor of the first coil conductor and the second coil conductor, respectively, have lengths in the second direction that are longer than lengths in the third direction, as described in any one of the appendices 1 to 11. [Note 13] A composite inductor according to any one of appendices 1 to 12, wherein the third conductor of each of the first coil conductor and the second coil conductor is bent outward in the third direction from the first conductor and the second conductor. [Note 14] A composite inductor as described in any one of the appendices 1 to 13, wherein the length of the third conductor of each of the first coil conductor and the second coil conductor in the third direction is longer than the length of the first conductor and the second conductor of each of the first coil conductor and the second coil conductor in the second direction. [Note 15] A composite inductor according to any one of the appendices 1 to 14, wherein the first magnetic material and the second magnetic material are constructed by laminating a plurality of magnetic thin strips, each composed of amorphous ribbons or nanocrystalline ribbons, in a first direction via an insulating layer. [Note 16] A composite inductor according to any one of the appendices 1 to 14, wherein the first magnetic material and the second magnetic material include a plurality of magnetic material blocks in which a plurality of magnetic thin strips composed of amorphous ribbons or nanocrystalline ribbons are stacked in a first direction with an insulating layer in between. [Note 17] The composite inductor according to Appendix 16, wherein the plurality of magnetic material blocks are stacked in the first direction. [Note 18] A composite inductor according to any one of the appendices 1 to 17, wherein the pair of fifth and sixth sides of the first magnetic material and the pair of eighth and ninth sides of the second magnetic material are uneven surfaces, and these uneven surfaces are in contact with the first part of the base body. [Note 19] The composite inductor according to any one of appendices 1 to 18, wherein the base body further comprises a second base body made of a resin-containing material that integrally covers one side in the first direction of the third conductor of each of the first coil conductor and the second coil conductor, one side in the first direction of one of the pair of fourth sides of the first magnetic material and one side in the first direction of the pair of seventh sides of the second magnetic material and one side in the first direction of the pair of first sides of the first base body of the base body. [Note 20] A composite inductor according to any one of appendices 1 to 19, wherein in a cross section perpendicular to the first direction, the first element portion of the element is also located outside the second magnetic material in the third direction. [Note 21] A composite inductor according to any one of appendices 1 to 20, wherein the element further comprises a third element that integrally covers the fourth side of the pair of fourth sides of the first magnetic material located on the other side in the first direction, the seventh side of the pair of seventh sides of the second magnetic material located on the other side in the first direction, and the first side of the pair of first sides of the first element located on the other side in the first direction. [Note 22] The first coil conductor and the second coil conductor further comprise a fourth conductor extending away from each other from the other end of each of the first conductors and the second conductor in the first direction, The composite inductor as described in Appendix 21, wherein one end of the fourth conductor in the first direction is embedded in the third element, and the other end of the fourth conductor in the first direction is exposed from the third element. [Note 23] A DC-DC converter equipped with a composite inductor as described in any one of the appendices 1 to 22. [Explanation of symbols]

[0062] 1...Inductor, 5...DC-DC converter, 10...Element, 11...First element, 12...Second element, 13...Third element, 20...Coil conductor, 20A...First coil conductor, 20B...Second coil conductor, 21...Parallel section, 22...Connecting section, 23...Terminal section, 30...Magnetic material, 30A...First magnetic material, 30B...Second magnetic material.

Claims

1. A body having a rectangular parallelepiped shape, a pair of first sides facing each other in a first direction, a pair of second sides facing each other in a second direction perpendicular to the first direction, and a pair of third sides facing each other in a third direction perpendicular to both the first and second directions, and having a first body portion made of a material including a magnetic material, A first coil conductor provided within the element, comprising a first conductor extending along the first direction, a second conductor extending along the first direction and adjacent to the first conductor in the second direction, and a third conductor extending along the second direction and connecting one end of the first conductor and the second conductor in the first direction, A second coil conductor is provided within the aforementioned body, and is arranged in the third direction with respect to the first coil conductor, and comprises the first conductor, the second conductor, and the third conductor, A first magnetic material is provided within the main body, has a rectangular parallelepiped shape, is interposed between the first coil conductor and the second coil conductor in the third direction, has a pair of fourth sides facing each other in the first direction, a pair of fifth sides facing each other in the second direction, and a pair of sixth sides facing each other in the third direction, and has a higher magnetic permeability than the first main body portion. Provided within the aforementioned element, having a rectangular parallelepiped shape, and located in a region different from the region where the first magnetic material is provided in a cross section perpendicular to the first direction, and comprising a pair of second magnetic materials having a pair of seventh sides facing each other in the first direction, a pair of eighth sides facing each other in the second direction, and a pair of ninth sides facing each other in the third direction, and having a higher magnetic permeability than the first element, A composite inductor in which, in a cross-section perpendicular to the first direction, the first element portion of the element is located at least outside the first conductor and the second conductor in the second direction of the first coil conductor and the second coil conductor, respectively.

2. The composite inductor according to claim 1, wherein in a cross section perpendicular to the first direction, the pair of second magnetic materials are located outside the first and second conductors of the first and second coil conductors in the third direction and extend along the second direction.

3. The composite inductor according to claim 1, wherein in a cross section perpendicular to the first direction, the pair of second magnetic materials are positioned between the first conductor and the second conductor of the first coil conductor and the second coil conductor, respectively.

4. The composite inductor according to claim 1, wherein in a cross section perpendicular to the first direction, the pair of second magnetic materials include a first portion that is located outside the first and second conductors of the first and second coil conductors in the third direction and extends along the second direction, and a second portion that is located between the first and second conductors of the first and second coil conductors, respectively, and the first portion and the second portion are connected.

5. The composite inductor according to claim 1, wherein the fourth side of the pair of fourth side surfaces of the first magnetic material located on one side in the first direction and the seventh side of the pair of seventh side surfaces of the second magnetic material located on one side in the first direction are located on the other side in the first direction from the one side in the first direction of the third conductor of each of the first coil conductor and the second coil conductor.

6. The composite inductor according to claim 1, wherein the pair of fifth sides of the first magnetic material and the pair of eighth sides of the second magnetic material protrude outward from the first and second conductors of the first and second coil conductors, respectively, and are in close proximity to the pair of second sides of the element.

7. The composite inductor according to claim 1, wherein, in a cross-section perpendicular to the first direction, the first element portion of the element is also located outside the first magnetic material and the second magnetic material in the second direction.

8. The composite inductor according to claim 7, wherein the length of the protrusion of the pair of fifth sides of the first magnetic material and the pair of eighth sides of the second magnetic material from the first conductor and the second conductor, respectively, of the first coil conductor and the second coil conductor is longer than the length of the first element portion of the element located outside the first magnetic material and the second magnetic material in the second direction.

9. The composite inductor according to claim 1, wherein, in a cross section perpendicular to the first direction, the length of the first element portion of the element located outside the first conductor and the second conductor in the second direction of each of the first coil conductor and the second coil conductor, with respect to the third direction, is longer than the length of the first conductor and the second conductor of each of the first coil conductor and the second coil conductor, with respect to the third direction.

10. The composite inductor according to claim 1, wherein in a cross section perpendicular to the first direction, the first conductor and the second conductor of the first coil conductor and the second coil conductor, respectively, are in contact with the first magnetic material.

11. The inductor according to claim 1, wherein in a cross section perpendicular to the first direction, the first conductor and the second conductor of the first coil conductor and the second coil conductor, respectively, are in contact with the second magnetic material.

12. The composite inductor according to claim 1, wherein, in a cross section perpendicular to the first direction, the length of the first conductor and the second conductor of the first coil conductor and the second coil conductor, respectively, is longer in the second direction than in the third direction.

13. The composite inductor according to claim 1, wherein the third conductor of each of the first coil conductor and the second coil conductor is bent outward in the third direction from the first conductor and the second conductor.

14. The composite inductor according to claim 1, wherein the length of the third conductor of each of the first coil conductor and the second coil conductor in the third direction is longer than the length of the first conductor and the second conductor of each of the first coil conductor and the second coil conductor in the second direction.

15. The composite inductor according to claim 1, wherein the first magnetic material and the second magnetic material are configured by stacking a plurality of magnetic thin strips, each composed of amorphous ribbon or nanocrystalline ribbon, in a first direction via an insulating layer.

16. The composite inductor according to claim 1, wherein the first magnetic material and the second magnetic material include a plurality of magnetic material blocks in which a plurality of magnetic thin strips, each composed of amorphous ribbons or nanocrystalline ribbons, are stacked in a first direction via an insulating layer.

17. The composite inductor according to claim 16, wherein the plurality of magnetic material blocks are stacked in the first direction.

18. The composite inductor according to claim 1, wherein the pair of fifth and sixth sides of the first magnetic body and the pair of eighth and ninth sides of the second magnetic body are uneven surfaces, and these uneven surfaces are in contact with the first element portion of the element.

19. The composite inductor according to claim 1, further comprising a second body portion made of a resin-containing material that integrally covers one side in the first direction of the third conductors of the first coil conductor and the second coil conductor, one side in the first direction of the pair of fourth sides of the first magnetic material and one side in the first direction of the pair of seventh sides of the second magnetic material, and one side in the first direction of the pair of first sides of the first body portion of the body.

20. The composite inductor according to claim 1, wherein in a cross-section perpendicular to the first direction, the first element portion of the element is also located outside the second magnetic material in the third direction.

21. The composite inductor according to claim 1, wherein the element further comprises a third element that integrally covers the fourth side of the pair of fourth side surfaces of the first magnetic material located on the other side in the first direction, the seventh side of the pair of seventh side surfaces of the second magnetic material located on the other side in the first direction, and the first side of the pair of first side surfaces of the first element that is located on the other side in the first direction.

22. The first coil conductor and the second coil conductor further comprise a fourth conductor extending away from each other from the other end of the first conductor and the second conductor in the first direction, The composite inductor according to claim 21, wherein one end of the fourth conductor in the first direction is embedded in the third element, and the other end of the fourth conductor in the first direction is exposed from the third element.

23. A DC-DC converter comprising the composite inductor described in claim 1.

Images