Inductor and DC-DC converter

Abstract

To provide an inductor and a DC-DC converter in which an inductance value is stabilized and improved.SOLUTION: In an inductor 1 and a DC-DC converter 500, even when an amount of an adhesive material 10 provided in a first region R1 is excessive in a facing region R of facing surfaces 4Aa, 4Ab, 4Ba, and 4Bb of conductor parts 4A and 4B, a part of the adhesive material 10 in a first region R1 is received in a second region R2, whereby the amount of the adhesive material 10 is leveled. Accordingly, a relative positional relationship between a magnetic block 2 and the conductor parts 4A and 4B of a coil conductor 3 is stabilized, and an inductance value is stabilized. In addition, since a magnetic volume is increased by a magnetic member 12 interposed between the magnetic block 2 and the opposing surfaces 4Aa, 4Ab, 4Ba, and 4Bb of the conductor parts 4A and 4B of the coil conductor 3 in the second region R2, the inductance value is also improved.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present disclosure relates to an inductor and a DC-DC converter. [Background technology]

[0002] Cited Document 1 discloses an inductor having a configuration in which a coil conductor (electrode) and a magnetic block (magnetic core) are bonded together with an adhesive. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-315610 Summary of the Invention [Problem to be solved by the invention]

[0004] The inventors conducted extensive research into the formation of adhesives that join coil conductors and magnetic blocks, and as a result, they discovered that the formation of adhesives affects the inductance value and discovered a new technology that can stabilize and increase the inductance value.

[0005] An object of one aspect of the present disclosure is to provide an inductor and a DC-DC converter that have a stable and improved inductance value. [Means for solving the problem]

[0006] An inductor according to one aspect of the present disclosure comprises a magnetic block, a coil conductor having a first conductor portion that is aligned with the magnetic block in a first direction, extends in a second direction perpendicular to the first direction, and has an opposing surface that includes an opposing region that faces the magnetic block in the first direction, and a resin member interposed between the magnetic block and the opposing region of the opposing surface of the first conductor portion of the coil conductor, wherein the opposing region of the opposing surface of the first conductor portion includes a first region in which the resin member is provided and a second region in which the width of the resin member in a third direction perpendicular to the first direction and the second direction is narrower than that of the first region or the resin member is not provided, and in the second region, the magnetic member is interposed between the magnetic block and the opposing surface of the first conductor portion of the coil conductor. [Effects of the Invention]

[0007] According to one aspect of the present disclosure, there is provided an inductor and a DC-DC converter with a stable and improved inductance value. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view of an inductor according to an embodiment. [Figure 2] FIG. 2 is a development view of the inductor shown in FIG. [Figure 3] FIG. 2 is a side view of the magnetic block and the coil conductor shown in FIG. [Figure 4] 1A is a side view of the adhesive material in the coil conductor from the Y-axis direction, and FIG. 1B is a side view of the adhesive material in the coil conductor from the X-axis direction. [Figure 5] 2 is a cross-sectional view of the inductor shown in FIG. 1 taken along line VV. [Figure 6] 2 is a diagram showing a circuit of a DC-DC converter in which the inductor shown in FIG. 1 is used. [Figure 7] 5A and 5B are a side view (a) and a side view (b) of the adhesive in the coil conductor from the Y-axis direction and the X-axis direction, respectively, in an embodiment different from that of FIG. 4. [Figure 8]5A and 5B are a side view (a) and a side view (b) of the adhesive in the coil conductor from the Y-axis direction and the X-axis direction, respectively, in an embodiment different from that of FIG. 4. DETAILED DESCRIPTION OF THE INVENTION

[0009] Preferred embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. In the description of the drawings, the same or equivalent elements are designated by the same reference numerals, and redundant description will be omitted.

[0010] First, the schematic configuration of an inductor 1 according to this embodiment will be described with reference to Figures 1 and 2. Figure 1 is a perspective view of the inductor 1 according to this embodiment. Figure 2 is a developed view of the inductor 1. Note that Figure 1 shows the inductor 1 mounted on a substrate 101.

[0011] In this embodiment, the inductor 1 is configured to include an element body 90, and a magnetic block 2 and coil conductor 3 provided within the element body 90. The magnetic block 2, which forms the core, and the coil conductor 3 are stacked in the X-axis direction. In this embodiment, the X-axis direction, the Y-axis direction, and the Z-axis direction are perpendicular to one another. The X-axis direction corresponds to the "first direction" in the claims, the Z-axis direction perpendicular to the X-axis direction corresponds to the "second direction" in the claims, and the Y-axis direction perpendicular to the X-axis and Z-axis directions corresponds to the "third direction" in the claims.

[0012] As shown in Fig. 1, the inductor 1 includes an element body 90 having a rectangular parallelepiped outer shape. In this embodiment, the outer shape of the element body 90 is formed by three pairs of surfaces that face each other in the X-axis direction, the Y-axis direction, and the Z-axis direction. The element body 90 can be made of magnetic resin. The magnetic resin is a resin that contains magnetic powder, and is, for example, a bound powder in which magnetic powder is bound by a binder resin.

[0013] The inductor 1 includes three magnetic blocks 2 and two coil conductors 3 inside an element body 90. The two coil conductors 3 (3A and 3B) included in the inductor 1 can be used as each choke coil in the circuit of a DC-DC converter 500 shown in Fig. 6. The DC-DC converter 500 is a multi-phase converter that includes a pair of conversion units made up of switching elements SW1 and SW2, choke coils 520A and 520B, and diodes D1 and D2, and in which these conversion units are connected in parallel, and the inductor 1 can be used as the choke coils 520A and 520B of each conversion unit. The configuration of the DC-DC converter 500 will be described in more detail. The DC-DC converter 500 includes a pair of input terminals A1 and A2, a pair of output terminals B1 and B2, a switching element SW1 and a choke coil 520A connected in series between the input terminal A1 and the output terminal B1, a switching element SW2 and a choke coil 520B connected in series between the input terminal A1 and the output terminal B1, and a capacitor C1 connected between the output terminals B1 and B2. The circuit consisting of the switching element SW1 and the choke coil 520A and the circuit consisting of the switching element SW2 and the choke coil 520B are connected in parallel between the input terminal A1 and the output terminal B1. The input terminal A2 and the output terminal B2 form a ground line. A diode D2 is connected in the reverse direction between the connection point of the switching element SW1 and the choke coil 520A and the ground line, and a diode D1 is connected in the reverse direction between the connection point of the switching element SW2 and the choke coil 520B and the ground line. The switching elements SW1 and SW2 are alternately turned on and off by a control circuit (not shown), thereby generating an output voltage that is a step-down of the input voltage. By configuring the pair of choke coils 520A and 520B in the DC-DC converter 500 using the pair of coil conductors 3A and 3B of the inductor 1, the number of parts constituting the DC-DC converter 500 can be reduced.

[0014] The three magnetic blocks 2 are composed of a first magnetic block 2A, a second magnetic block 2B, and a third magnetic block 2C. The first magnetic block 2A, the second magnetic block 2B, and the third magnetic block 2C are arranged in this order, facing each other at a distance in the X-axis direction. The magnetic blocks 2 have a rectangular parallelepiped shape. In this embodiment, the magnetic blocks 2 have a flat rectangular parallelepiped shape in the X-axis direction. The magnetic blocks 2 have the same shape. The magnetic blocks 2 can be made of a magnetic material, such as a sintered magnetic core such as MnZn ferrite or NiZn ferrite, or a laminated magnetic core formed by stacking soft magnetic metal plates. The magnetic permeability of the magnetic blocks 2 may be 1000 or more. The magnetic properties of the magnetic blocks 2 may be substantially the same or different.

[0015] Each of the three magnetic blocks 2A to 2C has a pair of main surfaces 2a and 2b, a pair of end surfaces 2c and 2d, and a pair of side surfaces 2e and 2f. The pair of main surfaces 2a and 2b face each other in the X-axis direction. The main surface 2a is located on the negative side of the X-axis direction, and the main surface 2b is located on the positive side of the X-axis direction. The pair of end surfaces 2c and 2d face each other in the Y-axis direction. The end surface 2c is located on the positive side of the Y-axis direction, and the end surface 2d is located on the negative side of the Y-axis direction. The pair of side surfaces 2e and 2f face each other in the Z-axis direction. The side surface 2e is located on the positive side of the Z-axis direction, and the side surface 2f is located on the negative side of the Z-axis direction.

[0016] 1, the magnetic blocks 2A to 2C are arranged at the same position in the YZ plane so that their end faces and side faces overlap each other when viewed from the X-axis direction. Note that misalignment within a range caused by manufacturing errors, etc., is considered to be included in the "same position."

[0017] The two coil conductors 3 are composed of a first coil conductor 3A and a second coil conductor 3B. The first coil conductor 3A and the second coil conductor 3B are arranged side by side along the X-axis direction, with the second magnetic block 2B in between. The first coil conductor 3A is disposed between the first magnetic block 2A and the second magnetic block 2B, and the second coil conductor 3B is disposed between the second magnetic block 2B and the third magnetic block 2C. The material of the coil conductor 3 is composed of a metal selected from, for example, Cu, Ag, Au, Al, Ni, Sn, etc.

[0018] The first coil conductor 3A includes a pair of conductor portions 4A, 4B, a connecting portion 6, and a pair of terminal portions 7A, 7B. The pair of conductor portions 4A, 4B each correspond to a "first conductor portion" in the claims, and the pair of terminal portions 7A, 7B each correspond to a "second conductor portion" in the claims.

[0019] The conductor portions 4A and 4B both extend in the Z-axis direction and are parallel to each other. The conductor portions 4A and 4B are arranged between the first magnetic block 2A and the second magnetic block 2B in the X-axis direction. The conductor portion 4A is arranged on the positive side of the Y-axis direction, and the conductor portion 4B is arranged on the negative side of the Y-axis direction. The conductor portions 4A and 4B do not have to be parallel to the Z-axis direction as long as they extend in the Z-axis direction.

[0020] The conductor portion 4A has a pair of opposing surfaces 4Aa, 4Ab and a pair of side surfaces 4Ac, 4Ad. The pair of opposing surfaces 4Aa, 4Ab face each other in the X-axis direction. The opposing surface 4Aa, located on the negative side of the X-axis direction, faces the first magnetic block 2A in the X-axis direction. The opposing surface 4Ab, located on the positive side of the X-axis direction, faces the second magnetic block 2B in the X-axis direction. The side surfaces 4Ac, 4Ad face each other in the Y-axis direction. The side surface 4Ac is located on the positive side of the Y-axis direction, and the side surface 4Ad is located on the negative side of the Y-axis direction. The conductor portion 4B has a pair of opposing surfaces 4Ba, 4Bb and a pair of side surfaces 4Bc, 4Bd. The pair of opposing surfaces 4Ba, 4Bb face each other in the X-axis direction. The opposing surface 4Ba, located on the negative side of the X-axis direction, faces the first magnetic block 2A in the X-axis direction. The opposing surface 4Bb, located on the positive side of the X-axis direction, faces the second magnetic block 2B in the X-axis direction. The side surfaces 4Bc and 4Bd face each other in the Y-axis direction. The side surface 4Bc is located on the negative side in the Y-axis direction, and the side surface 4Bd is located on the positive side in the Y-axis direction.

[0021] The connecting portion 6 is a member that connects the conductor portion 4A and the conductor portion 4B. The connecting portion 6 connects one end of the conductor portions 4A and 4B (i.e., the end portions on the positive side in the Z-axis direction) to each other and extends in the Y-axis direction. The connecting portion 6 does not have to be parallel to the Y-axis direction as long as it extends in the Y-axis direction.

[0022] The terminal portion 7A is provided at the other end of the conductor portion 4A (i.e., the end on the negative side in the Z-axis direction) and extends toward the negative side in the X-axis direction and the positive side in the Y-axis direction. The terminal portion 7A is configured by forming a portion of the conductor portion 4A near the other end so that it widens toward the positive side in the Y-axis direction and bending the wide portion toward the negative side in the X-axis direction. The terminal portion 7B is provided at the other end of the conductor portion 4B (i.e., the end on the negative side in the Z-axis direction) and extends toward the negative side in the X-axis direction and the negative side in the Y-axis direction. The terminal portion 7B is formed by forming a portion of the conductor portion 4B near the other end so that it widens toward the negative side in the Y-axis direction and bending the wide portion toward the negative side in the X-axis direction. The first magnetic block 2A adjacent to the first coil conductor 3A on the negative side in the X-axis direction is placed on the terminal portions 7A and 7B of the first coil conductor 3A. The terminal portions 7A and 7B are joined to land electrodes 102 of a substrate 101 on which the inductor 1 is mounted.

[0023] Like the first coil conductor 3A, the second coil conductor 3B includes a pair of conductor portions 4A and 4B, a connecting portion 6, and a pair of terminal portions 7A and 7B. Unlike the first coil conductor 3A, the second coil conductor 3B has the terminal portion 7A extending from the other end of the conductor portion 4A toward the positive side in the X-axis direction and the positive side in the Y-axis direction, and the terminal portion 7B extending from the other end of the conductor portion 4B toward the positive side in the X-axis direction and the negative side in the Y-axis direction. The third magnetic block 2C, which is adjacent to the second coil conductor 3B on the positive side in the X-axis direction, is placed on the terminal portions 7A and 7B of the second coil conductor 3B. The terminal portions 7A and 7B of the second coil conductor 3B are also bonded to land electrodes 102 of a substrate 101 on which the inductor 1 is mounted.

[0024] The negative Z-axis direction surfaces of the terminal portions 7A, 7B of the first coil conductor 3A and the terminal portions 7A, 7B of the second coil conductor 3B are both exposed from the element body 90, and the exposed portions are joined to the land electrode 102. Furthermore, a portion of the surface of the terminal portions 7A, 7B of the first coil conductor 3A and the terminal portions 7A, 7B of the second coil conductor 3B adjacent to the negative Z-axis direction surfaces may be exposed from the element body 90, the portion being located on the negative Z-axis direction.

[0025] An adhesive 10 (resin member) is interposed between each of the magnetic blocks 2 and each of the coil conductors 3, and the magnetic blocks 2 and the coil conductors 3 are bonded together by the adhesive 10. Specifically, the adhesive 10 is provided on each of the opposing surfaces 4Aa, 4Ab of the conductor portion 4A of each of the coil conductors 3 and the opposing surfaces 4Ba, 4Bb of the conductor portion 4B. More specifically, the adhesive 10 is provided in each of the opposing regions R of the opposing surfaces 4Aa, 4Ab, 4Ba, and 4Bb that face the magnetic block 2. The adhesive 10 can be provided in the opposing region R using a known application technique using a nozzle or the like. The adhesive 10 may be made of a material in which a filler is dispersed in a resin. The filler may be a magnetic material or a non-magnetic material.

[0026] The adhesive 10 in the facing region R of the facing surface 4Aa of the conductor portion 4A will be described below with reference to Fig. 4. The facing surfaces 4Ab, 4Ba, and 4Bb other than the facing surface 4Aa of the conductor portion 4A are the same as or similar to the facing surface 4Aa of the conductor portion 4A, and therefore descriptions thereof will be omitted.

[0027] As shown in FIG. 4, the adhesive 10 is not provided entirely in the facing region R of the facing surface 4Aa, but is provided partially in the facing region R. Specifically, in a side view (FIG. 4(a)) seen from the Y-axis direction, the facing region R includes a first region R1 where the adhesive 10 is provided and a second region R2 where the adhesive 10 is not provided. In this embodiment, the first region R1 includes two first regions R11 and R12, and the second region R2 includes three second regions R21, R22, and R23. In each first region R1, the adhesive 10 has an elliptical shape extending in the Z-axis direction. As shown in FIG. 4(b), when viewed from the X-axis direction, each first region R1 may include a region where the adhesive 10 is not provided (i.e., an outer region of the ellipse). In each second region R2, a magnetic member 12 is interposed between the magnetic block 2A and the conductor portion 4A of the coil conductor 3A. In this embodiment, the magnetic member 12 is a magnetic resin that constitutes the element body 90, and flows into each second region R2 when the magnetic block 2 and the coil conductor 3 are integrally molded with the magnetic resin.

[0028] The first regions R11 and R12 are spaced apart in the Z direction, with the first region R11 located on the other end side of the conductor portion 4A (i.e., the terminal portion 7A side) and the first region R12 located on one end side of the conductor portion 4A (i.e., the connecting portion 6 side).

[0029] The second region R21 is located between the first regions R11 and R12. The second region R21 is located in the middle M of the magnetic block 2A, in the Z-axis direction, where the opposing region R of the opposing surface 4Aa faces. The second region R22 is located closer to the other end of the conductor portion 4A than the first region R11. The second region R23 is located closer to one end of the conductor portion 4A than the first region R12.

[0030] The adhesive 10 may be completely contained within the opposing region R of each opposing surface 4Aa, 4Ab, 4Ba, and 4Bb, or may protrude from the opposing region R of each opposing surface 4Aa, 4Ab, 4Ba, and 4Bb. As shown in Fig. 5, the adhesive 10 may include, in addition to a first portion 10a interposed between the magnetic block 2 and the opposing region R of the opposing surfaces 4Aa, 4Ab, 4Ba, and 4Bb of the conductor portions 4A and 4B of the coil conductor 3, a second portion 10b extending from the first portion 10a and provided in a region of the magnetic block 2 adjacent to the region facing the opposing region R. The second portion 10b increases the bonding strength between the magnetic block 2 and the resin member constituting the element body 90. The adhesive 10 may further include a third portion 10c provided on a surface adjacent to the opposing surfaces 4Aa, 4Ab, 4Ba, and 4Bb of the conductor portions 4A and 4B of the coil conductor 3 and connected to the second portion 10b. The third portion 10c may extend in a fillet shape from the second portion 10b. The third portion 10c increases the bonding strength between the magnetic block 2 and the coil conductor 3.

[0031] In the inductor 1 and DC-DC converter 500 described above, even if the amount of adhesive 10 provided in the first region R1 of the opposing surfaces 4Aa, 4Ab, 4Ba, and 4Bb of the conductor portions 4A and 4B is excessive, some of the adhesive 10 in the first region R1 is received in the second region R2, thereby leveling out the amount of adhesive 10. This stabilizes the relative positional relationship between the magnetic block 2 and the conductor portions 4A and 4B of the coil conductor 3, thereby stabilizing the inductance value. In addition, the magnetic volume is increased by the magnetic member 12 interposed between the magnetic block 2 and the opposing surfaces 4Aa, 4Ab, 4Ba, and 4Bb of the conductor portions 4A and 4B of the coil conductor 3 in the second region R2, thereby improving the inductance value.

[0032] In the inductor 1, the facing region R includes multiple first regions R11 and R12, which support the magnetic block 2 and the conductor portions 4A and 4B of the coil conductor 3 at multiple locations. This reduces the likelihood of the magnetic block 2 and the conductor portions 4A and 4B of the coil conductor 3 tilting relative to each other, further stabilizing their relative positional relationship. In particular, as shown in FIG. 4, the second region R21 is located at the middle M of the magnetic block 2A, and the first regions R11 and R12 are located on both sides of it in the Z-axis direction, further reducing tilt between the magnetic block 2 and the conductor portions 4A and 4B of the coil conductor 3. The second regions R22 and R23 contribute to reducing the amount of adhesive 10 used and also contribute to improving the inductance value by allowing the magnetic member 12 to penetrate. However, the first region R12 may be arranged to extend to the end of the facing region R on the positive side in the Z-axis direction. In this case, the second region R23 may be omitted. Alternatively, the first region R11 may be disposed so as to extend to the end of the opposing region R on the negative side in the Z-axis direction, in which case the second region R22 may be omitted.

[0033] Inductor 1 can achieve a high inductance value because element body 90 that seals magnetic block 2 and coil conductor 3 is made of magnetic resin.

[0034] The inductor 1 is not limited to the above-described embodiment, and various modifications are possible without departing from the spirit of the invention.

[0035] For example, the second region R2 may be completely free of adhesive 10, or may be provided with adhesive 10 as long as the length in the Y-axis direction (i.e., width) is narrower than that of the adhesive 10 provided in the first region R1. For example, as shown in FIG. 7, each first region R1 may be provided with adhesive 10 of uniform width (specifically, rectangular), and the second region R2 may also be provided with adhesive that is narrower than that of the adhesive 10 in the first region R1. In this case, in the facing region R, the adhesive 10 has an I-shape extending in the Z-direction. As shown in FIG. 7(b), when viewed from the X-axis direction, each second region R2 has a region where no adhesive 10 is provided (i.e., both side regions in the Y-axis direction), and a magnetic member 12 may be present in this region. 8, in the case where two elliptical adhesive materials 10 are connected in the Z direction, the region where the adhesive material 10 is wide can be defined as a first region R1, and the region where the adhesive material 10 is narrow can be defined as a second region R2. For example, a certain percentage (e.g., 80%) of the maximum width W of the adhesive material 10 can be defined as a threshold, and the region where the adhesive material 10 is wider than the threshold can be defined as the first region R1, and the region where the adhesive material 10 is narrower than the threshold can be defined as the second region R2. Note that, in the embodiment shown in FIG. 4, instead of defining the first region R1 where the adhesive material 10 is present and the second region R2 where the adhesive material 10 is not present, the region can be defined as the first region R1 where the adhesive material 10 is wider than a predetermined threshold and the second region R2 where the adhesive material 10 is narrower than a predetermined threshold.

[0036] Since the adhesive 10 is not provided over the entire facing region R of the facing surface 4Aa, the amount of adhesive 10 used can be reduced. The ratio of the area of ​​the adhesive 10 to the area of ​​the facing region R is less than 100%, and can be in the range of 20 to 90%, for example. Furthermore, in consideration of achieving both an improvement in inductance value and adhesion, the ratio may be in the range of 50 to 70%.

[0037] If the adhesive 10 is magnetic, the inductance value can be further improved. Furthermore, if the adhesive 10 contains a filler, the filler further stabilizes the relative positional relationship between the magnetic block 2 and the conductor portions 4A, 4B of the coil conductor 3. When the average particle size of the filler in the adhesive 10 is compared with the average particle size of the magnetic powder contained in the magnetic member 12 (for example, the magnetic resin of the base body), if the average particle size of the magnetic powder contained in the magnetic member 12 is smaller than the average particle size of the filler in the adhesive 10, the eddy current loss in the second region R2 can be reduced.

[0038] The number of first regions R1 in each facing region R may be one or more (for example, three or more). The number of second regions R2 in each facing region R may be one or more.

[0039] As can be understood from the above description, the present specification discloses the following. [Appendix 1] A magnetic block; a coil conductor having a first conductor portion aligned with the magnetic block in a first direction, extending in a second direction perpendicular to the first direction, and having an opposing surface including an opposing region opposing the magnetic block in the first direction; a resin member interposed between the magnetic block and an opposing region of the opposing surface of the first conductor portion of the coil conductor; Equipped with an opposing region of the opposing surface of the first conductor portion includes a first region in which the resin member is provided and a second region in which the width of the resin member in a third direction orthogonal to the first direction and the second direction is narrower than that of the first region or in which the resin member is not provided; an inductor, wherein a magnetic member is interposed between the magnetic block and the opposing surface of the first conductor portion of the coil conductor in the second region; [Appendix 2] the magnetic block, at least a portion of the coil conductor, and the resin member are provided inside the element body made of magnetic resin; 2. The inductor according to claim 1, wherein the magnetic member is a magnetic resin that constitutes the base body. [Appendix 3] the opposing regions of the opposing surfaces of the first conductor include a plurality of the first regions arranged in the second direction, 3. The inductor according to claim 1, wherein the second region is located between adjacent first regions in the second direction. [Appendix 4] 4. The inductor according to any one of Supplementary Note 3, wherein the second region is located midway between the magnetic blocks that the opposing regions of the opposing surfaces face in the second direction. [Appendix 5] the coil conductor further includes a second conductor portion connected to one end of the first conductor portion and extending in the first direction from the one end; 5. The inductor according to any one of appendixes 1 to 4, wherein the second region is located closer to the other end of the first conductor than the first region, which is closer to the other end of the first conductor. [Appendix 6] An inductor as described in Appendix 5, wherein the opposing region of the opposing surface of the first conductor portion further includes the second region located closer to one end of the first conductor portion than the first region closer to one end of the first conductor portion. [Appendix 7] An inductor described in any one of Appendices 1 to 6, wherein the resin member includes a first portion interposed between the magnetic block and an opposing region of the opposing surface of the first conductor portion of the coil conductor, and a second portion extending from the first portion and provided in an adjacent region of the magnetic block that faces the opposing region. [Appendix 8] The inductor described in Appendix 7, wherein the resin member further includes a third portion provided on a surface of the coil conductor adjacent to the opposing surface of the first conductor portion and connected to the second portion. [Appendix 9] 9. The inductor according to any one of claims 1 to 8, wherein the resin member contains a filler. [Appendix 10] 10. The inductor of claim 9, wherein the filler is a magnetic material. [Appendix 11] the magnetic member is a magnetic resin containing magnetic powder, 10. The inductor according to claim 9, wherein the average particle size of the magnetic powder in the magnetic resin is smaller than the average particle size of the filler in the resin member. [Appendix 12] A DC-DC converter comprising the inductor according to any one of Supplementary Notes 1 to 11. [Explanation of symbols]

[0040] 1...inductor, 2...magnetic block, 3...coil conductor, 4A, 4B...conductor portion, 6...connecting portion, 7A, 7B...terminal portion, 10...adhesive, 12...magnetic member, 90...element body, 500...DC-DC converter, R...opposing region, R1...first region, R2...second region.

Claims

1. A magnetic block; a coil conductor including a first conductor portion aligned with the magnetic block in a first direction, extending in a second direction perpendicular to the first direction, and having an opposing surface including an opposing region opposing the magnetic block in the first direction; a resin member interposed between the magnetic block and an opposing region of the opposing surface of the first conductor portion of the coil conductor; Equipped with an opposing region of the opposing surface of the first conductor portion includes a first region in which the resin member is provided and a second region in which the width of the resin member in a third direction orthogonal to the first direction and the second direction is narrower than that of the first region or in which the resin member is not provided, an inductor, wherein a magnetic member is interposed between the magnetic block and the opposing surface of the first conductor portion of the coil conductor in the second region;

2. the magnetic block, at least a portion of the coil conductor, and the resin member are provided inside the element body made of magnetic resin; The inductor according to claim 1 , wherein the magnetic member is a magnetic resin that constitutes the element body.

3. the opposing regions of the opposing surfaces of the first conductor include a plurality of the first regions aligned in the second direction, The inductor according to claim 1 , wherein the second region is located between adjacent first regions in the second direction.

4. The inductor according to claim 3 , wherein the second region is located midway between the magnetic blocks that are opposed by the opposing regions of the opposing surfaces in the second direction.

5. the coil conductor further includes a second conductor portion connected to one end of the first conductor portion and extending in the first direction from the one end, The inductor according to claim 1 , wherein the second region is located closer to the other end of the first conductor than the first region, which is closer to the other end of the first conductor.

6. 6. The inductor according to claim 5, wherein the opposing regions of the opposing surfaces of the first conductor portion further include the second region located closer to one end side of the first conductor portion than the first region closer to one end side of the first conductor portion.

7. 2. The inductor of claim 1, wherein the resin member includes a first portion interposed between the magnetic block and an opposing region of the opposing surface of the first conductor portion of the coil conductor, and a second portion extending from the first portion and provided in an adjacent region of the magnetic block that faces the opposing region.

8. The inductor according to claim 7 , wherein the resin member further includes a third portion provided on a surface of the coil conductor adjacent to the opposing surface of the first conductor portion and connected to the second portion.

9. The inductor according to claim 1 , wherein the resin member contains a filler.

10. The inductor of claim 9 , wherein the filler is a magnetic material.

11. the magnetic member is a magnetic resin containing magnetic powder, The inductor according to claim 9 , wherein the average particle size of the magnetic powder in the magnetic resin is smaller than the average particle size of the filler in the resin member.

12. A DC-DC converter comprising the inductor according to claim 1.

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