Multilayer coil components

Abstract

To provide a laminated coil component with a compact configuration that can achieve desired characteristics with ease.SOLUTION: In a laminated coil component 1, a coil 10 is arranged in an element body 2. The coil 10 includes a plurality of coil conductors 7. The plurality of coil conductors 7 include first, second, and third end parts 21, 22, and 23. The first, second, and third end parts 21, 22, and 23 are exposed from the element body 2 on a first surface 2a, and coupled with a first external electrode 4. The first, second, and third end parts 21, 22, and 23 are along the first surface 2a and arranged in a first direction in this order when seen from a second direction orthogonal to the first direction. The first end part 21 and the third end part 23 are at least partially overlapped with each other when seen from the first direction. Each of the first end part 21 and the third end part 23 has a region not overlapped with the second end part 22 when seen from the first direction.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a laminated coil component. [Background technology]

[0002] A multilayer coil component is known that includes an element body, a coil disposed inside the element body, and a pair of external electrodes electrically connected to each other via the coil (see, for example, Patent Document 1). The element body includes first and second surfaces. The coil includes a plurality of coil conductors electrically connected to each other. The pair of external electrodes includes a first external electrode provided on the first surface and a second external electrode provided on the second surface. The plurality of coil conductors include a plurality of end portions exposed from the element body on the first surface and connected to the first external electrode. These end portions are aligned in the first direction when viewed from a second direction that is along the first surface and perpendicular to the first direction. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-050022 Summary of the Invention [Problem to be solved by the invention]

[0004] As described above, it has been considered to provide a laminated coil component with multiple end portions electrically connected to each other. In this case, the DC resistance of the coil formed by multiple coil conductors can be reduced. However, if the multiple end portions overlap when viewed from the first direction, a proximity effect occurs due to the current passing through each end portion, which may degrade the characteristics of the laminated coil component. For example, a magnetic field generated by a current flowing through one end portion may affect the current flowing through the other end portion. If the multiple end portions overlap when viewed from the first direction, stray capacitance may occur at the end portions, which may reduce the self-resonant frequency (SRF).

[0005] In order to suppress the adverse effects caused by the above-described proximity of the multiple end portions, it is conceivable to increase the distance between the end portions. However, the greater the distance between the end portions in the first direction, the more difficult it is to achieve a compact laminated coil component. The greater the distance between the end portions in the second direction, the greater the current path difference between the coil conductors including the end portions. If the current path difference between the coil conductors is large, there is a risk that the characteristics of the laminated coil component will deteriorate. For example, the greater the current path difference between the coil conductors, the higher the DC resistance in the coil conductors. Therefore, there is a risk that the characteristics of the entire laminated coil component will change depending on the current path difference between the coil conductors.

[0006] An object of one aspect of the present invention is to provide a laminated coil component that can easily achieve desired characteristics with a compact configuration. [Means for solving the problem]

[0007] A laminated coil component according to one aspect of the present invention comprises an element body, a coil, and a pair of external electrodes. The element body includes first and second surfaces. The coil is disposed inside the element body. The coil includes a plurality of coil conductors. The plurality of coil conductors are stacked in a first direction and electrically connected to each other. The pair of external electrodes are disposed on the outer surface of the element body at a distance from each other. The pair of external electrodes are electrically connected to each other via the plurality of coil conductors. The pair of external electrodes includes a first external electrode and a second external electrode. The first external electrode is provided on the first surface. The second external electrode is provided on the second surface. The plurality of coil conductors are exposed from the element body on the first surface and connected to the first external electrode. The plurality of coil conductors include first, second, and third end portions. The first, second, and third end portions are aligned in order in the first direction when viewed from a second direction that is along the first surface and perpendicular to the first direction. The first end portion and the third end portion at least partially overlap each other when viewed from the first direction. The first end and the third end each have an area that does not overlap with the second end when viewed from the first direction.

[0008] In this laminated coil component, the first end and the third end at least partially overlap each other when viewed from the first direction, which allows the laminated coil component to be made more compact and reduces the difference in current paths between the coil conductors. Reducing the difference in current paths between the coil conductors makes it easier to ensure desired characteristics. Each of the first end and the third end has a region that does not overlap with the second end when viewed from the first direction, which makes it easier to suppress the proximity effect due to current passing through the end and the occurrence of stray capacitance at the end. Therefore, desired characteristics can be easily achieved in a compact configuration.

[0009] In the above-described one aspect, the second end portion may include a region that does not overlap with the first end portion and a region that does not overlap with the third end portion when viewed from the first direction, in which case the proximity effect between the first and third ends and the second end portion, and the stray capacitance at the second end portion can be further reduced.

[0010] In one of the above aspects, the second end portion may have a region that does not overlap with either the first end portion or the third end portion when viewed from the first direction. In this case, the laminated coil component may be configured so that the region where the first end portion and the third end portion overlap when viewed from the first direction is relatively large. This makes it possible to reduce the size of the laminated coil component and to reduce variations in the current paths of the coil conductors. Reducing variations in the current paths of the coil conductors makes it easier to ensure desired characteristics.

[0011] In one aspect, the multiple coil conductors may include a first coil conductor, a second coil conductor, and a third coil conductor. The first coil conductor may include a first end. The second coil conductor may include a second end. The third coil conductor may include a third end. The lengths of the current paths of the first and third coil conductors may be shorter than the length of the current path of the second coil conductor. In this case, of the first, second, and third ends, the current paths of the first and third ends are shorter than the current path of the second end. Therefore, the DC resistance of the multiple coil conductors including the first, second, and third ends can be further reduced.

[0012] In the above-described one aspect, the first coil conductor may extend linearly from a connecting portion where the first coil conductor and the first external electrode are connected in a third direction intersecting the first and second directions, in which case the current path at the first end can be configured to be the shortest.

[0013] In the above aspect, the coil may have a coil axis extending in a first direction. In the second direction, the shortest distance between the second end and the coil axis may be shorter than the shortest distance between the first end and the coil axis. In this case, the laminated coil component can be made compact while ensuring a space for arranging the second end.

[0014] In one aspect, the first end and the third end may not overlap with the second end when viewed from the first direction, which can further reduce the proximity effect between the first and third ends and the second end, and the stray capacitance at the second end.

[0015] In one of the above aspects, the multiple coil conductors may include a first conductor group and a second conductor group. The first conductor group may include multiple end portions exposed from the element body on the first surface and connected to the first external electrode. The second conductor group may include at least one end portion exposed from the element body on the second surface and connected to the second external electrode. The first conductor group may include a first end portion, a second end portion, and a third end portion. The number of end portions included in the second conductor group may be fewer than the number of end portions included in the first conductor group. In this case, a desired magnetic path length can be ensured by configuring the number of end portions included in the second conductor group to be different from the number of end portions included in the first conductor group. Because the number of end portions included in the second conductor group is fewer than the number of end portions included in the first conductor group, the proximity effect and the influence of stray capacitance in the second conductor group can be easily reduced.

[0016] In one of the above embodiments, the number of ends in the second conductor group may be 1. In this case, since the number of ends included in the second conductor group is 1, the proximity effect does not occur in the second conductor group, and the influence of stray capacitance at the ends can be further reduced.

[0017] In one of the above aspects, the multiple coil conductors may further include a fourth end portion. The fourth end portion is exposed from the element body on the first surface and connected to the first external electrode. The first, second, third, and fourth end portions may be aligned in order in the first direction when viewed from the second direction. The second end portion and the fourth end portion may at least partially overlap each other in the first direction. Each of the second end portion and the fourth end portion may have an area that does not overlap with the third end portion when viewed from the first direction. In this case, even if there are four or more end portions exposed from the element body on the first surface, compactness can be achieved and desired characteristics can be easily achieved. [Effects of the Invention]

[0018] One aspect of the present invention provides a laminated coil component that can easily achieve desired characteristics with a compact configuration. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 1 is a perspective view of a laminated coil component according to an embodiment of the present invention. [Figure 2] FIG. 2 is a cross-sectional view of the laminated coil component taken along line II-II. [Figure 3] FIG. 3 is a cross-sectional view of the laminated coil component taken along line III-III. [Figure 4] FIG. 4 is a cross-sectional view of the laminated coil component taken along line IV-IV. [Figure 5] FIG. 4 is a partially enlarged cross-sectional view of the laminated coil component taken along line IV-IV. [Figure 6] FIG. 10 is a partially enlarged view of a cross section of a laminated coil component according to a modified example of the present embodiment. [Figure 7] FIG. 10 is a partially enlarged view of a cross section of a laminated coil component according to a modified example of the present embodiment. [Figure 8] FIG. 10 is a partially enlarged view of a cross section of a laminated coil component according to a modified example of the present embodiment. [Figure 9] 1A is a cross-sectional view showing a portion of a laminated coil component according to a comparative example, and FIG. 1B is a cross-sectional view showing a portion of an example of a laminated coil component according to the present embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, embodiments of the present invention will be described in detail 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.

[0021] First, a schematic configuration of a laminated coil component 1 according to this embodiment will be described with reference to FIGS. 1 to 5. FIG. 1 is a perspective view of the laminated coil component 1 according to this embodiment. FIGS. 2 to 4 are cross-sectional views of the laminated coil component 1 according to this embodiment. FIG. 2 is a cross-sectional view of the laminated coil component taken along line II-II. FIG. 3 is a cross-sectional view of the laminated coil component taken along line III-III. FIG. 4 is a cross-sectional view of the laminated coil component taken along line IV-IV. FIG. 5 is a partially enlarged view of the cross-section shown in FIG. 4. The X-axis direction, Y-axis direction, and Z-axis direction intersect with each other. In this embodiment, the X-axis direction, Y-axis direction, and Z-axis direction are perpendicular to each other. The X-axis direction corresponds to a first direction, the Z-axis direction corresponds to a second direction, and the Y-axis direction corresponds to a third direction.

[0022] As shown in FIG. 1, the laminated coil component 1 includes an element body 2 and a pair of external electrodes 4 and 5. For example, if the external electrode 4 is a first external electrode, the external electrode 5 corresponds to a second external electrode. The laminated coil component 1 is mounted, for example, by soldering to an electronic device. The electronic device includes, for example, a circuit board or an electronic component. In this embodiment, the element body 2 is formed of multiple layers stacked in the Z-axis direction. The multiple layers are, for example, ceramic sheets. The element body 2 is formed, for example, by heat treatment after the multiple layers have been stacked. The heat treatment temperature is, for example, about 850 to 900°C.

[0023] The element body 2 has, for example, insulating properties. The element body 2 is made of, for example, a magnetic material. The magnetic material includes, for example, at least one selected from a Ni-Cu-Zn ferrite material, a Ni-Cu-Zn-Mg ferrite material, and a Ni-Cu ferrite material. The magnetic material that makes up the element body 2 may include an Fe alloy or the like. The element body 2 may be made of a non-magnetic material. The non-magnetic material includes, for example, at least one selected from a glass ceramic material and a dielectric material.

[0024] The element body 2 has, for example, a rectangular parallelepiped shape. The rectangular parallelepiped shape includes a rectangular parallelepiped shape with chamfered corners and ridges and a rectangular parallelepiped shape with rounded corners and ridges. The shape of the element body 2 is not limited to a rectangular parallelepiped shape. For example, the element body 2 may have a cylindrical shape. The element body 2 has, as its outer surfaces, a pair of end faces 2a and 2b, a pair of side faces 2c and 2d, and a pair of main faces 2e and 2f. The area of ​​each of the main faces 2e and 2f is larger than the area of ​​any of the end face 2a, the end face 2b, the side face 2c, and the side face 2d. The main faces 2e and 2f are also side faces of the rectangular parallelepiped element body 2. In the laminated coil component 1, one side face 2d is a mounting surface to be mounted on an electronic device. In the laminated coil component 1, one side face 2d faces the electronic device. When the end face 2a corresponds to the first surface, the end face 2b corresponds to the second surface.

[0025] The pair of end faces 2a, 2b face each other in the Y-axis direction. The pair of side faces 2c, 2d face each other in the Z-axis direction. The pair of main faces 2e, 2f face each other in the X-axis direction. The element body 2 has, for example, a length in the Z-axis direction that is smaller than its length in the Y-axis direction. The element body 2 has, for example, a length in the X-axis direction that is smaller than its lengths in the Y-axis and Z-axis directions. The length ratios of the element body 2 in the X-axis, Y-axis, and Z-axis directions are not limited to these. The Y-axis direction is, for example, the longitudinal direction. The X-axis direction is, for example, the width direction. The Z-axis direction is, for example, the height direction.

[0026] The pair of external electrodes 4, 5 are spaced apart and arranged on the outer surface of the element body 2. The pair of external electrodes 4, 5 face each other in the Y-axis direction. The pair of external electrodes 4, 5 are spaced apart from each other in the Y-axis direction.

[0027] The pair of external electrodes 4, 5 are formed by a known method. The pair of external electrodes 4, 5 are made of, for example, a metal material. The metal material is, for example, copper, silver, gold, nickel, or chromium. The pair of external electrodes 4, 5 are formed, for example, by plating an electrode layer. The electrode layer is made of, for example, a conductive paste. The conductive paste is applied, for example, by a dipping method, a printing method, or a transfer method. The plating method is, for example, electrolytic plating or electroless plating. This plating method forms a plating layer on the outer surface of the conductive paste.

[0028] The external electrode 4 includes, for example, portions 4a, 4b, and 4c. The portion 4a of the external electrode 4 is provided on the end face 2a. The portion 4b of the external electrode 4 is provided on a pair of side faces 2c and 2d. The portion 4c of the external electrode 4 is provided on a pair of main faces 2e and 2f. The portion 4a of the external electrode 4 covers, for example, the entire end face 2a. The portions 4b and 4c of the external electrode 4 cover, for example, a pair of side faces 2c and 2d and a portion of the pair of main faces 2e and 2f. The portion 4a of the external electrode 4 is connected to the portions 4b and 4c of the external electrode 4.

[0029] On each of the side surfaces 2c and 2d, the area covered by the portion 4b of the external electrode 4 has, for example, a rectangular shape. On each of the main surfaces 2e and 2f, the area covered by the portion 4c of the external electrode 4 has, for example, a rectangular shape. In this specification, "connected" means connected in a state of direct contact. "Directly contacting" means connected to each other without going through other members shown in this specification. "Directly contacting" does not exclude connection via members not explicitly shown in this specification.

[0030] The external electrode 5 includes, for example, portions 5a, 5b, and 5c. The portion 5a of the external electrode 5 is provided on the end face 2a. The portion 5b of the external electrode 5 is provided on a pair of side faces 2c and 2d. The portion 5c of the external electrode 5 is provided on a pair of main faces 2e and 2f. The portion 5a of the external electrode 5 covers, for example, the entire end face 2a. The portions 5b and 5c of the external electrode 5 cover, for example, the pair of side faces 2c and 2d and parts of the pair of main faces 2e and 2f. The portion 5a of the external electrode 5 is connected to the portions 5b and 5c of the external electrode 5. On each of the side faces 2c and 2d, the area covered by the portion 5b of the external electrode 5 has, for example, a rectangular shape. On each of the main faces 2e and 2f, the area covered by the portion 5c of the external electrode 5 has, for example, a rectangular shape.

[0031] As shown in FIGS. 2 and 3 , the laminated coil component 1 further includes a coil 10 disposed inside the element body 2. The coil 10 includes a plurality of coil conductors 7 and a plurality of vias 8. The plurality of coil conductors 7 are stacked in the X-axis direction. Each coil conductor 7 corresponds to an internal conductor layer. Each via 8 corresponds to a connecting conductor. Each via 8 passes through the element body 2 located between a pair of coil conductors 7 and connects the pair of coil conductors 7. The plurality of coil conductors 7 are electrically connected to each other through the plurality of vias 8. The plurality of coil conductors 7 and the plurality of vias 8 are made of a conductive material. The conductive material includes, for example, at least one selected from Ag and Pd.

[0032] The coil 10 is formed by a plurality of coil conductors 7 and a plurality of vias 8. The coil 10 electrically connects the external electrode 4 and the external electrode 5. In other words, the pair of external electrodes 4, 5 are electrically connected to each other via the plurality of coil conductors 7. The coil 10 is configured, for example, with a triple winding and a single winding. The coil 10 has a coil axis AX extending parallel to the X-axis direction. The plurality of vias 8 overlap when viewed from the X-axis direction. In the laminated coil component 1, the coil 10 has a spiral structure that progresses counterclockwise along the X-axis direction.

[0033] 2 and 3 , the multiple coil conductors 7 include a first conductor group 7α and a second conductor group 7β. In the laminated coil component 1, the first conductor group 7α and the second conductor group 7β each include multiple coil conductors 7. The multiple coil conductors 7 include a first coil conductor 11, a second coil conductor 12, and a third coil conductor 13. In the present embodiment, the first conductor group 7α and the second conductor group 7β each include the first coil conductor 11, the second coil conductor 12, and the third coil conductor 13.

[0034] The coil 10 includes an annular portion 15 formed in a ring shape when viewed in the extension direction of the coil axis AX. The coil axis AX is located at the geometric center of the annular portion 15 when viewed in the X-axis direction. The coil 10 also includes an extension portion 16 connecting the annular portion 15 to the external electrode 4, and an extension portion 17 connecting the annular portion 15 to the external electrode 5. The annular portion 15 and the extension portions 16 and 17 are formed by a first conductor group 7α and a second conductor group 7β. The extension portion 16 is included in the first conductor group 7α. The extension portion 17 is included in the second conductor group 7β.

[0035] The extending portion 16 of the first conductor group 7α includes a plurality of end portions 20. The end portions 20 correspond to the tips of the coil 10. The multiple end portions 20 are exposed from the element body 2 at the end face 2a and are connected to the portion 4a of the external electrode 4. The extending portion 17 of the second conductor group 7β includes at least one end portion 30. The end portion 30 corresponds to the tip of the coil 10. At least one end portion 30 is exposed from the element body 2 at the end face 2b and is connected to the portion 5a of the external electrode 5. In the laminated coil component 1, the second conductor group 7β includes a plurality of end portions 30.

[0036] In the first conductor group 7α and the second conductor group 7β of this embodiment, the multiple end portions 20 and the multiple end portions 30 respectively include a first end portion 21, a second end portion 22, and a third end portion 23. The first end portion 21 is included in the first coil conductor 11. The second end portion 22 is included in the second coil conductor 12. The third end portion 23 is included in the third coil conductor 13. The first end portion 21, the second end portion 22, and the third end portion 23 are exposed from the element body 2 at the end surface 2a and connected to the portion 4a of the external electrode 4.

[0037] As a modification of this embodiment, the second conductor group 7β may not include the second coil conductor 12. In this case, for example, the distance in the Z-axis direction between the first coil conductor 11 and the third coil conductor 13 in the second conductor group 7β is greater than the distance in the Z-axis direction between the first coil conductor 11 and the second coil conductor 12 in the first conductor group 7α. The distance in the Z-axis direction between the first coil conductor 11 and the third coil conductor 13 in the second conductor group 7β is greater than the distance in the Z-axis direction between the third coil conductor 13 and the second coil conductor 12 in the first conductor group 7α. For example, the number of end portions 30 included in the second conductor group 7β may be fewer than the number of end portions 20 included in the first conductor group 7α. As a further modification of this embodiment, the second conductor group 7β may include only one coil conductor 7.

[0038] As shown in FIGS. 3 to 5 , the first end 21, the second end 22, and the third end 23 are lined up in order in the X-axis direction when viewed from the Z-axis direction. In other words, the multiple end portions 20 are arranged in the X-axis direction in the order of the first end portion 21, the second end portion 22, and the third end portion 23. The X-axis direction and the Z-axis direction are along the end surface 2a. Among the multiple end portions 20, the first end portion 21 and the second end portion 22 are adjacent to each other when viewed from the Z-axis direction. Among the multiple end portions 20, the second end portion 22 and the third end portion 23 are adjacent to each other when viewed from the Z-axis direction. The second end portion 22 is disposed between the first end portion 21 and the third end portion 23 when viewed from the Z-axis direction.

[0039] As shown in FIG. 5 , the first end 21 has a region R1 that does not overlap with the second end 22 when viewed from the X-axis direction. The third end 23 has a region R2 that does not overlap with the second end 22 when viewed from the X-axis direction. In the laminated coil component 1, the region R1 and the region R2 are identical. The second end 22 includes a region R3 that does not overlap with the first end 21 and a region R4 that does not overlap with the third end 23 when viewed from the X-axis direction. In the laminated coil component 1, the region R3 and the region R4 are identical. In the laminated coil component 1, the regions R3 and R4 of the second end 22 do not overlap with either the first end 21 or the third end 23 when viewed from the X-axis direction.

[0040] The first end 21 and the third end 23 at least partially face each other in the X-axis direction. The first end 21 and the third end 23 at least partially overlap each other when viewed from the X-axis direction. The first end 21 and the third end 23 overlap each other in region R5 when viewed from the X-axis direction.

[0041] The first end 21, the second end 22, and the third end 23 have, for example, the same width T1 in the Z-axis direction. The second end 22 is shifted from the first end 21 and the third end 23 in the Z-axis direction by a shift width T2. The second end 22 is farther from the side surface 2c in the Z-axis direction than the first end 21 and the third end 23. In the laminated coil component 1, the shift width T2 is smaller than the width T1. Therefore, the second end 22 overlaps with the first end 21 and the third end 23 as viewed in the X-axis direction. With the above configuration, the first end 21, the second end 22, and the third end 23 are arranged in a V-shape as viewed in the Y-axis direction.

[0042] In the laminated coil component 1, the length of the current path of the first coil conductor 11 including the first end 21 is shorter than the length of the current path of the second coil conductor 12 including the second end 22. The length of the current path of the third coil conductor 13 including the third end 23 is shorter than the length of the current path of the second coil conductor 12 including the second end 22. The length of the current path of the first coil conductor 11 including the first end 21 is equal to the length of the current path of the third coil conductor 13 including the third end 23.

[0043] In the first conductor group 7α, the "length of the current path of each coil conductor 7" is the length of the current path from the connecting portion 20a connecting the external electrode 4 and the coil conductor 7 to the connecting portion 8a connecting the coil conductor 7 to the via 8. In the second conductor group 7β, the "length of the current path of each coil conductor 7" is the length of the current path from the connecting portion 30a connecting the external electrode 5 and the coil conductor 7 to the connecting portion 8a connecting the coil conductor 7 to the via 8. The "current path of the coil conductor 7" is the path through which current flows in the coil conductor 7 when a current is passed between the external electrodes 4 and 5 of the multilayer coil component 1. For example, the current path of the coil conductor 7 is the shortest path on the coil conductor 7 from one end of the coil conductor 7 to the other end of the coil conductor.

[0044] In the extension portions 16 and 17 of this embodiment, the first coil conductor 11 extends linearly in the Y-axis direction from the connecting portions 20a and 30a between the first coil conductor 11 and the external electrodes 4 and 5. In the extension portions 16 and 17, the third coil conductor 13 extends linearly in the Y-axis direction from the connecting portions 20a and 30a between the third coil conductor 13 and the external electrodes 4 and 5. In the extension portions 16 and 17, the second coil conductor 12 extends in a curved manner in the Y-axis direction from the connecting portions 20a and 30a between the second coil conductor 12 and the external electrodes 4 and 5. When viewed from the Y-axis direction, the shortest distance between the second end portion 22 and the coil axis AX in the X-axis direction is smaller than the shortest distance between the first end portion 21 and the coil axis AX in the X-axis direction. When viewed from the Y-axis direction, the shortest distance between the second end portion 22 and the coil axis AX in the X-axis direction is smaller than the shortest distance between the third end portion 23 and the coil axis AX in the X-axis direction.

[0045] Next, laminated coil components 1A, 1B, and 1C according to modifications of this embodiment will be described with reference to FIGS. 6 to 8. FIG. 6 is a partially enlarged view of a cross section of the laminated coil component 1A. FIG. 7 is a partially enlarged view of a cross section of the laminated coil component 1B. FIG. 8 is a partially enlarged view of a cross section of the laminated coil component 1C. The positions of the cross sections shown in FIGS. 6 to 8 correspond to the position of the cross section taken along line IV-IV of the laminated coil component 1. These modifications are generally similar to or the same as the above-described laminated coil component 1. Differences from the above-described laminated coil component 1 will be mainly described below.

[0046] First, the laminated coil component 1A will be described. The laminated coil component 1A shown in FIG. 6 differs from the above-described embodiment in terms of the arrangement of the multiple end portions 20. In the laminated coil component 1A, the multiple end portions 20 include a first end portion 21A, a second end portion 22A, and a third end portion 23A. The first end portion 21A corresponds to the first end portion 21. The second end portion 22A corresponds to the second end portion 22. The third end portion 23A corresponds to the third end portion 23.

[0047] The first end portion 21A has a region R1 that does not overlap with the second end portion 22A when viewed from the X-axis direction. The third end portion 23A has a region R2 that does not overlap with the second end portion 22A when viewed from the X-axis direction. In the laminated coil component 1A, the region R1 and the region R2 are identical. The second end portion 22A includes a region R3 that does not overlap with the first end portion 21A and a region R4 that does not overlap with the third end portion 23A when viewed from the X-axis direction. In the laminated coil component 1A, the region R3 and the region R4 are identical. The first end portion 21A and the third end portion 23A overlap with each other in a region R5 when viewed from the X-axis direction.

[0048] The first end portion 21A, the second end portion 22A, and the third end portion 23A have, for example, the same width T3 in the Z-axis direction. The second end portion 22A is shifted from the first end portion 21A and the third end portion 23A in the Z-axis direction by a shift width T4. The second end portion 22A is farther from the side surface 2c in the Z-axis direction than the first end portion 21A and the third end portion 23A. In the laminated coil component 1A, the shift width T4 is larger than the width T3. Therefore, the first end portion 21A and the third end portion 23A do not overlap with the second end portion 22A when viewed in the X-axis direction.

[0049] Next, the laminated coil component 1B will be described. The laminated coil component 1B shown in FIG. 7 differs from the above-described embodiment in terms of the arrangement of the multiple end portions 20. In the laminated coil component 1B, the multiple end portions 20 include a first end portion 21B, a second end portion 22B, and a third end portion 23B. The first end portion 21B corresponds to the first end portion 21. The second end portion 22B corresponds to the second end portion 22. The third end portion 23B corresponds to the third end portion 23. In the laminated coil component 1B, the first end portion 21B and the third end portion 23B are misaligned in the Z-axis direction.

[0050] The first end portion 21B has a region R1 that does not overlap with the second end portion 22B when viewed from the X-axis direction. The third end portion 23B has a region R2 that does not overlap with the second end portion 22B when viewed from the X-axis direction. In the laminated coil component 1B, the regions R1 and R2 are shifted in the Z-axis direction. The second end portion 22B includes a region R3 that does not overlap with the first end portion 21B and a region R4 that does not overlap with the third end portion 23B when viewed from the X-axis direction. In the laminated coil component 1B, the regions R3 and R4 are shifted in the Z-axis direction. The first end portion 21B and the third end portion 23B overlap with each other in a region R5 when viewed from the X-axis direction.

[0051] The first end portion 21B, the second end portion 22B, and the third end portion 23B have, for example, the same width T5 in the Z-axis direction. The second end portion 22B is shifted from the first end portion 21B in the Z-axis direction by a shift width T6. The second end portion 22B is farther away from the side surface 2c in the Z-axis direction than the first end portion 21B. In the laminated coil component 1B, the shift width T6 is smaller than the width T5. Therefore, the second end portion 22B overlaps with the first end portion 21B when viewed in the X-axis direction. The second end 22B is offset from the third end 23B in the Z-axis direction by an offset width T7. The second end 22B is farther from the side surface 2c in the Z-axis direction than the third end 23. In the laminated coil component 1B, the offset width T7 is smaller than the width T5. Therefore, the second end 22B overlaps with the third end 23B when viewed in the X-axis direction. With the above configuration, the first end 21B, the second end 22B, and the third end 23B are arranged in stages in the Y-axis direction so as to be progressively farther from the side surface 2c.

[0052] In the laminated coil component 1B, the length of the current path of the first coil conductor 11 including the first end portion 21B is shorter than the length of the current path of the second coil conductor 12 including the second end portion 22B. The length of the current path of the third coil conductor 13 including the third end portion 23B is longer than the length of the current path of the second coil conductor 12 including the second end portion 22B. The length of the current path of the first coil conductor 11 including the first end portion 21B is shorter than the length of the current path of the third coil conductor 13 including the third end portion 23B.

[0053] In the extending portions 16, 17 of the laminated coil component 1B, the first coil conductor 11 extends linearly in the Y-axis direction from the connecting portions 20a, 30a connecting the first coil conductor 11 and the external electrodes 4, 5. In the extending portions 16, 17, the third coil conductor 13 of the laminated coil component 1B extends in a curved manner in the Y-axis direction from the connecting portions 20a, 30a connecting the third coil conductor 13 and the external electrodes 4, 5. In the extending portions 16, 17, the second coil conductor 12 extends in a curved manner in the Y-axis direction from the connecting portions 20a, 30a connecting the second coil conductor 12 and the external electrodes 4, 5. When viewed from the Y-axis direction, the shortest distance between the second end portion 22B and the coil axis AX in the X-axis direction is smaller than the shortest distance between the first end portion 21B and the coil axis AX in the X-axis direction. When viewed from the Y-axis direction, the shortest distance between the second end portion 22B and the coil axis AX in the X-axis direction is larger than the shortest distance between the third end portion 23B and the coil axis AX in the X-axis direction.

[0054] Next, a laminated coil component 1C will be described. The laminated coil component 1C shown in FIG. 8 differs from the above-described embodiment in the number of the multiple end portions 20. In the laminated coil component 1C, the multiple end portions 20 include a first end portion 21C, a second end portion 22C, and a third end portion 23C. The first end portion 21C corresponds to the first end portion 21. The second end portion 22C corresponds to the second end portion 22. The third end portion 23C corresponds to the third end portion 23. In the laminated coil component 1C, the multiple coil conductors 7 further include a fourth end portion 24C that is exposed from the element body 2 at the end surface 2a and is connected to the external electrode 4.

[0055] The first end 21C, the second end 22C, the third end 23C, and the fourth end 24C are aligned in this order in the X-axis direction as viewed in the Z-axis direction. As shown in Fig. 8, the multiple end portions 20 are arranged in the X-axis direction in the order of the first end portion 21C, the second end portion 22C, the third end portion 23C, and the fourth end portion 24C. Among the multiple end portions 20, the third end portion 23C and the fourth end portion 24C are adjacent to each other as viewed in the Z-axis direction. The third end portion 23C is disposed between the second end portion 22C and the fourth end portion 24C as viewed in the Z-axis direction.

[0056] The first end portion 21C has a region R1 that does not overlap with the second end portion 22C when viewed from the X-axis direction. The third end portion 23C has a region R2 that does not overlap with the second end portion 22C when viewed from the X-axis direction. In the laminated coil component 1C, the region R1 and the region R2 are identical. The second end portion 22C includes a region R3 that does not overlap with the first end portion 21C and a region R4 that does not overlap with the third end portion 23C when viewed from the X-axis direction. In the laminated coil component 1C, the region R3 and the region R4 are identical. The first end portion 21C and the third end portion 23C overlap with each other in a region R5 when viewed from the X-axis direction.

[0057] In this modification, the second end 22C and the fourth end 24C at least partially face each other in the X-axis direction. The second end 22C and the fourth end 24C at least partially overlap each other when viewed in the X-axis direction. The second end 22C and the fourth end 24C overlap each other in a region R6 when viewed in the X-axis direction. Like the second end 22C, the fourth end 24C includes a region R3 that does not overlap with the first end 21C and a region R4 that does not overlap with the third end 23C when viewed in the X-axis direction.

[0058] The first end portion 21C, the second end portion 22C, the third end portion 23C, and the fourth end portion 24C have, for example, the same width T1 in the Z-axis direction. The second end portion 22C and the fourth end portion 24C are shifted from the first end portion 21C in the Z-axis direction by a shift width T2. The second end portion 22C and the fourth end portion 24C are farther from the side surface 2c in the Z-axis direction than the first end portion 21C. In the laminated coil component 1C, the shift width T2 is smaller than the width T1. Therefore, the second end portion 22C and the fourth end portion 24C overlap with the first end portion 21C when viewed in the X-axis direction.

[0059] Next, the effects of the laminated coil components 1, 1A, 1B, and 1C according to the present embodiment and the modifications will be described.

[0060] In the laminated coil component 1, the first end portion 21 and the third end portion 23 at least partially overlap each other when viewed from the X-axis direction. This allows the laminated coil component 1 to be made more compact, and the difference in current paths between the coil conductors 7 can be reduced. Reducing the difference in current paths between the coil conductors 7 makes it easier to ensure desired characteristics. The first end portion 21 and the third end portion 23 each have regions R1 and R2 that do not overlap with the second end portion 22 when viewed from the X-axis direction, thereby suppressing the proximity effect caused by the current passing through the ends 20 and 30 and the occurrence of stray capacitance at the ends. This makes it easier to achieve desired characteristics in a compact configuration. The laminated coil components 1A, 1B, and 1C also have a similar configuration.

[0061] In the laminated coil component 1, the second end portion 22 includes, when viewed from the X-axis direction, a region R3 that does not overlap with the first end portion 21 and a region R4 that does not overlap with the third end portion 23. In this case, the proximity effect between the first and third end portions 21, 23 and the second end portion 22, and the stray capacitance at the second end portion can be further reduced. The laminated coil components 1A, 1B, and 1C also have a similar configuration.

[0062] Fig. 9(a) is a cross-sectional view showing a portion of the laminated structure of a laminated coil component of a comparative example. Fig. 9(b) is a cross-sectional view showing a portion of an example of a laminated coil component according to this embodiment. Figs. 9(a) and 9(b) show a state in which a pair of external electrodes 4, 5 or portions equivalent thereto have been removed from the laminated coil component. In Figs. 9(a) and 9(b), widths L1 and L2, which will be described later, are depicted in a deformed manner.

[0063] The laminated coil component of the comparative example shown in FIG. 9( a) includes an element body 102 corresponding to the element body 2, a plurality of coil conductors 107 corresponding to the plurality of coil conductors 7, and a plurality of vias 8. The element body 102 includes end faces 102a and 102b corresponding to the end faces 2a and 2b, respectively. The plurality of coil conductors 107 form a coil 110. The plurality of coil conductors 107 include a conductor group 107α corresponding to the first conductor group 7α and a conductor group 107β corresponding to the second conductor group 7β. The conductor group 107α includes an extension portion 116 corresponding to the extension portion 16. The conductor group 107β includes an extension portion 117 corresponding to the extension portion 17. The extension portion 116 includes a plurality of end portions 120 corresponding to the plurality of end portions 20. The extension portion 117 includes a plurality of end portions 130 corresponding to the plurality of end portions 30.

[0064] The multiple end portions 120 completely overlap when viewed from the X-axis direction and do not have regions R1, R2, R3, or R4. The edges of the multiple end portions 120 coincide when viewed from the X-axis direction. The multiple end portions 120 completely overlap when viewed from the X-axis direction and do not have regions R1, R2, R3, or R4. The edges of the multiple end portions 130 coincide when viewed from the X-axis direction. In this structure, the end faces 102a and 102b of the element body 102 protrude by a width L1 in the Y-axis direction along the multiple end portions 120 and the multiple end portions 130. The protrusion of the end faces 102a and 102b in the Y-axis direction occurs due to contraction during the formation of the element body 102. When the element body 102 contracts, the element body 102 is pulled by the surfaces of the multiple coil conductors 107 and deforms along the surfaces of the multiple coil conductors 107. The contraction of the element body 102 occurs, for example, during heat treatment during the formation of the element body 102.

[0065] In the laminated coil components 1, 1A, 1B, and 1C, the protrusion of the end faces 2a and 2b of the element body 2 in the Y-axis direction is reduced. For example, the width L2 of the protrusion of the end faces 2a and 2b in the Y-axis direction is smaller than the width L1 of the protrusion of the end faces 102a and 102b in the Y-axis direction. This structure results from the fact that the end faces 20 and 30 do not completely overlap when viewed from the X-axis direction, and at least one end 20, 30 is shifted in the Z-axis direction. For example, in the laminated coil component 1, the first end 21 and the third end 23 each have regions R1 and R2 that do not overlap with the second end 22 when viewed from the X-axis direction, and the second end 22 has regions R3 and R4 that do not overlap with the first end 21 and the third end 23 when viewed from the X-axis direction. Therefore, when the element body 2 contracts, the force pulling the element body 2 toward the surfaces of the multiple coil conductors 7 is dispersed. This is thought to be the result of the reduced protrusion of the end faces 2a and 2b of the element body 2 in the Y-axis direction.

[0066] In the laminated coil component 1, the second end 22 has regions R3 and R4 that do not overlap with either the first end 21 or the third end 23 when viewed from the X-axis direction. In this case, the laminated coil component 1 can be configured so that the region R5 where the first end 21 and the third end 23 overlap when viewed from the X-axis direction is relatively large. This makes it possible to make the laminated coil component 1 more compact and reduce variations in the current paths of the coil conductors 7. Reducing variations in the current paths of the coil conductors 7 makes it easier to ensure desired characteristics. The laminated coil components 1A and 1C also have a similar configuration.

[0067] In the laminated coil component 1, the multiple coil conductors 7 include a first coil conductor 11, a second coil conductor 12, and a third coil conductor 13. The first coil conductor 11 includes a first end portion 21. The second coil conductor 12 includes a second end portion 22. The third coil conductor 13 includes a third end portion 23. The length of the current path in the first and third coil conductors 11 and 13 is shorter than the length of the current path in the second coil conductor 12. In this case, among the first, second, and third end portions 21, 22, and 23, the current path in the first and third end portions 21 and 23 is shorter than the current path in the second end portion 22. This can further reduce the DC resistance of the multiple coil conductors 7 including the first, second, and third end portions 21, 22, and 23. The laminated coil components 1A and 1C also have a similar configuration.

[0068] In the laminated coil component 1, the first coil conductor 11 extends linearly in the Y-axis direction from a connecting portion 20a where the first coil conductor 11 and the external electrode 4 are connected. In this case, the current path of the first end portion 21 can be configured to be the shortest. The laminated coil components 1A, 1B, and 1C also have a similar configuration.

[0069] In the laminated coil component 1, the multiple coil conductors 7 form a coil 10 having a coil axis AX extending in the X-axis direction. In the Z-axis direction, the shortest distance between the second end portion 22 and the coil axis AX is shorter than the shortest distance between the first end portion 21 and the coil axis AX. In this case, the laminated coil component 1 can be made compact while ensuring sufficient space for arranging the second end portion 22. The laminated coil components 1A, 1B, and 1C also have a similar configuration.

[0070] In the laminated coil component 1A, the first end portion 21A and the third end portion 23A do not overlap with the second end portion 22A when viewed in the X-axis direction. In this case, the proximity effect between the first and third end portions 21A, 23A and the second end portion 22A, and the stray capacitance at the second end portion 22A can be further reduced.

[0071] The multiple coil conductors 7 may include a first conductor group 7α and a second conductor group 7β. The first conductor group 7α may include multiple end portions 20 exposed from the element body 2 at the end face 2a and connected to the external electrode 4. The second conductor group 7β may include at least one end portion 30 exposed from the element body 2 at the end face 2b and connected to the external electrode 5. The first conductor group 7α may include a first end portion 21, a second end portion 22, and a third end portion 23. The number of end portions 30 included in the second conductor group 7β may be fewer than the number of end portions 20 included in the first conductor group 7α. In this case, a desired magnetic path length can be ensured by configuring the number of end portions 30 included in the second conductor group 7β to be different from the number of end portions 20 included in the first conductor group 7α. Because the number of end portions 30 included in the second conductor group 7β is fewer than the number of end portions 20 included in the first conductor group 7α, the proximity effect and the influence of stray capacitance in the second conductor group 7β can be easily reduced.

[0072] The number of the end portions 30 in the second conductor group 7β may be 1. In this case, since the number of the end portions 30 included in the second conductor group 7β is 1, the proximity effect does not occur in the second conductor group 7β, and the influence of stray capacitance at the end portions 30 can be further reduced.

[0073] In the laminated coil component 1C, the multiple coil conductors 7 further include a fourth end portion 24C. The fourth end portion 24C is exposed from the element body 2 at the end surface 2a and connected to the external electrode 4. The first, second, third, and fourth end portions 21C, 22C, 23C, and 24C are aligned in order in the X-axis direction as viewed from the Z-axis direction. The second end portion 22C and the fourth end portion 24C at least partially overlap each other in the X-axis direction. Each of the second end portion 22C and the fourth end portion 24C has a region R4 that does not overlap with the third end portion 23C as viewed from the X-axis direction. In this case, even if four or more end portions 20 are exposed from the element body 2 at the end surface 2a, compactness can be achieved and desired characteristics can be easily achieved.

[0074] The above describes embodiments and modifications of the present invention, but the present invention is not necessarily limited to the above-described embodiments and modifications, and various modifications are possible without departing from the spirit of the present invention.

[0075] For example, the laminated coil components 1, 1A, 1B, and 1C are not limited to a configuration in which the coil axis AX of the coil 10 extends in the X-axis direction. The coil 10 may be configured to have a coil axis AX extending in the Z-axis direction.

[0076] For example, the configuration of the laminated coil component 1C may be combined with the configuration of the laminated coil component 1A. For example, in the laminated coil component 1C, like the laminated coil component 1A, the first end portion 21C and the third end portion 23C may not overlap with each other as with the second end portion 22C and the fourth end portion 24C, respectively, when viewed in the X-axis direction. In this case, the first end portion 21C, the second end portion 22C, the third end portion 23C, and the fourth end portion 24C are arranged in a zigzag pattern when viewed in the Y-axis direction.

[0077] For example, the configuration of the laminated coil component 1C may be combined with the configuration of the laminated coil component 1B. For example, in the laminated coil component 1C, the first end portion 21C, the second end portion 22C, the third end portion 23C, and the fourth end portion 24C may be arranged in steps in the Y-axis direction so as to be spaced apart in that order from the side surface 2c, similar to the laminated coil component 1B. [Explanation of symbols]

[0078] 1, 1A, 1B, 1C... multilayer coil component, 2... element body, 4, 5... external electrode, 7... coil conductor, 7α... first conductor group, 7β... second conductor group, 10... coil, 11... first coil conductor, 12... second coil conductor, 13... third coil conductor, 20, 30... end, 21, 21A, 21B, 21C... first end, 22, 22A, 22B, 22C... second end, 23, 23A, 23B, 23C... third end, 24C... fourth end, AX... coil axis, R1, R2, R3, R4, R5, R6... region.

Claims

1. an element body including a first and a second surface; a coil disposed inside the element body, the coil including a plurality of coil conductors stacked in a first direction and electrically connected to each other; a pair of external electrodes spaced apart from each other and disposed on the outer surface of the element body, and electrically connected to each other via the plurality of coil conductors; the pair of external electrodes includes a first external electrode provided on the first surface and a second external electrode provided on the second surface, the plurality of coil conductors include first, second, and third end portions exposed from the element body on the first surface and connected to the first external electrode, and include a first coil conductor including the first end portion, a second coil conductor including the second end portion, and a third coil conductor including the third end portion; the first, second, and third ends are aligned in order in the first direction when viewed from a second direction that is along the first surface and perpendicular to the first direction, the first end portion and the third end portion at least partially overlap each other when viewed from the first direction, each of the first end and the third end has a region that does not overlap with the second end when viewed from the first direction; each of the plurality of coil conductors includes an annular portion formed in an annular shape and an extending portion connecting the annular portion and the first external electrode; the extending portion of the first coil conductor extends linearly toward the first end portion, the extending portion of the second coil conductor extends in a curved manner toward the second end portion.

2. 2. The laminated coil component according to claim 1, wherein the second end portion includes, when viewed from the first direction, a region that does not overlap with the first end portion and a region that does not overlap with the third end portion.

3. 3. The laminated coil component according to claim 1, wherein the second end portion has a region that does not overlap with either the first end portion or the third end portion when viewed from the first direction.

4. the plurality of coil conductors include a first coil conductor including the first end, a second coil conductor including the second end, and a third coil conductor including the third end; The laminated coil component according to claim 3 , wherein lengths of the current paths of the first and third coil conductors are shorter than a length of the current path of the second coil conductor.

5. 5. The laminated coil component according to claim 4, wherein the first coil conductor extends linearly from a connecting portion where the first coil conductor and the first external electrode are connected in a third direction intersecting the first and second directions.

6. The coil has a coil axis extending in the first direction, 6. The laminated coil component according to claim 1, wherein a shortest distance between the second end portion and the coil axis in the second direction is shorter than a shortest distance between the first end portion and the coil axis.

7. The laminated coil component according to claim 1 , wherein the first end portion and the third end portion do not overlap with the second end portion when viewed from the first direction.

8. the plurality of coil conductors include a first conductor group including a plurality of end portions exposed from the element body on the first surface and connected to the first external electrode, and a second conductor group including at least one end portion exposed from the element body on the second surface and connected to the second external electrode, the first conductor group includes the first end, the second end, and the third end; The laminated coil component according to claim 1 , wherein the number of the end portions included in the second conductor group is smaller than the number of the end portions included in the first conductor group.

9. The laminated coil component according to claim 8 , wherein the number of the end portions in the second conductor group is one.

10. the plurality of coil conductors further include fourth ends exposed from the element body on the first surface and connected to the first external electrode; When viewed from the second direction, the first, second, third, and fourth ends are aligned in order in the first direction, the second end and the fourth end at least partially overlap each other in the first direction, 10. The laminated coil component according to claim 1, wherein each of the second end portion and the fourth end portion has a region that does not overlap with the third end portion when viewed from the first direction.

Images