Common mode filter

Abstract

The technical problem of the present invention is to achieve higher common mode attenuation characteristics and lower differential insertion loss characteristics in a common mode filter having a structure in which a magnetic body is disposed in an inner diameter region surrounded by a coil pattern. A common mode filter (1) is provided with coil patterns (110, 210) and a magnetic body (3) disposed in an inner diameter region (A). The inner diameter region (A) includes regions (A1, A2) located on the + X direction side and the-X direction side, respectively, when viewed from a virtual line (Ly) extending in the Y direction, which is the short side direction. The coil patterns (110, 210) have sections (111, 211) and sections (112, 212) located on the + X direction side and the-X direction side, respectively, when viewed from a virtual line (Ly). The number of the coil conductors constituting the sections (111, 211) is one more than the number of the coil conductors constituting the sections (112, 212). The magnetic body (3) is disposed so as to be offset toward the region (A2) side.

Description

Technical Field

[0001] This disclosure relates to a common-mode filter, and more particularly to a common-mode filter having a plurality of coil patterns stacked via an insulating layer. Background Technology

[0002] Patent Document 1 discloses a chip-type common-mode filter having two coil patterns stacked via an insulating layer. When viewed from above in the stacking direction, the common-mode filter described in Patent Document 1 has a magnetic material disposed in the inner diameter region surrounded by the coil patterns.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 4683071 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] In this common-mode filter, higher common-mode attenuation characteristics and lower differential insertion loss characteristics are sought with a limited planar size.

[0008] This disclosure describes a technique for achieving higher common-mode attenuation characteristics and lower differential insertion loss characteristics in a common-mode filter having a structure in which a magnetic body is arranged in an inner diameter region surrounded by a coil pattern.

[0009] means for solving problems

[0010] A common-mode filter according to one aspect of the present disclosure comprises: a first coil pattern having a plurality of spiral turns wound in a spiral manner; a second coil pattern having a plurality of spiral turns wound in a spiral manner stacked on the first coil pattern via an insulating layer; and a magnetic body disposed, when viewed from a top view in a stacking direction, in an inner diameter region surrounded by the first coil pattern and the second coil pattern, the inner diameter region having a shape in which the dimension in a first direction is larger than the dimension in a second direction orthogonal to the first direction, the inner diameter region comprising: a first region located on one side in the first direction when viewed from a virtual line passing through the center of the inner diameter region and extending along the second direction; and a second region located on the other side in the first direction when viewed from the virtual line, the first coil pattern being surrounded by the first coil pattern. The second coil pattern includes: a first section located on one side of a first direction when viewed from a virtual line; and a second section located on the other side of the first direction when viewed from a virtual line. The second coil pattern includes: a third section located on one side of the first direction when viewed from a virtual line; and a fourth section located on the other side of the first direction when viewed from a virtual line. The number of coil conductors constituting the first section is one more in at least a portion of the circumferential positions than the number of coil conductors constituting the second section in at least a portion of the circumferential positions. The number of coil conductors constituting the third section is one more in at least a portion of the circumferential positions than the number of coil conductors constituting the fourth section in at least a portion of the circumferential positions. The magnetic body is disposed offset towards the second region side.

[0011] Invention Effects

[0012] According to this disclosure, a technique is provided to achieve higher common-mode attenuation characteristics and lower differential insertion loss characteristics in a common-mode filter having a structure in which a magnetic body is arranged in an inner diameter region surrounded by a coil pattern. Attached Figure Description

[0013] Figure 1 This is a general perspective view showing the appearance of a common-mode filter 1 according to one embodiment of the present disclosure.

[0014] Figure 2 This is a top view to illustrate the general shape of the pattern of conductor layer 100.

[0015] Figure 3 This is a rough top view of the insulating layer 10.

[0016] Figure 4 This is a top view to illustrate the general shape of the pattern of conductor layer 200.

[0017] Figure 5 This is a rough top view of the insulating layer 20.

[0018] Figure 6 This is a top view to illustrate the general shape of the conductor layer 300 pattern.

[0019] Figure 7 This is a rough top view of the insulating layer 30.

[0020] Figure 8 This is the equivalent circuit diagram of common-mode filter 1.

[0021] Figure 9 This is a general top view to illustrate the pattern shape of the conductor layer 100A according to the modified example.

[0022] Figure 10 This is a general top view of the insulating layer 10A according to the modified example.

[0023] Figure 11 This is a general top view to illustrate the pattern shape of the conductor layer 200A according to the modified example.

[0024] Figure 12 This is a general top view of the insulating layer 20A according to the modified example.

[0025] Figure 13 This is a general top view to illustrate the pattern shape of the conductor layer 300A according to the modified example.

[0026] Figure 14 This is a general top view of the insulating layer 30A according to the modified example.

[0027] Explanation of reference numerals in the attached figures

[0028] 1 Common-mode filter

[0029] 2 body

[0030] 3-5 magnetic bodies

[0031] 3a Convex edge

[0032] 3b Concave edge

[0033] 10, 10A, 20, 20A, 30, 30A insulation layers

[0034] Openings 11–15, 17, 21–27, 31–34, and 37

[0035] 100, 100A, 200, 200A, 300, 300A conductor layers

[0036] 110 and 210 coil patterns

[0037] 110A, 210A peripheral end

[0038] 110B, 210B inner peripheral end

[0039] Intervals 111, 112, 211, 212

[0040] Lead-out sections 113, 213, 325a, and 326b

[0041] Connecting patterns 121-125, 221-226, and 321-326

[0042] A inner diameter area

[0043] Areas A1 and A2

[0044] E1~E4 terminal electrodes

[0045] Lx, Ly virtual lines

[0046] R1, R2 circumferential positions Detailed Implementation

[0047] Hereinafter, with reference to the accompanying drawings, embodiments of the technology involved in this disclosure will be described in detail.

[0048] Figure 1 This is a general perspective view showing the appearance of a common-mode filter 1 according to one embodiment of the present disclosure.

[0049] The common-mode filter 1 according to the first embodiment is a surface-mount chip component, such as... Figure 1 As shown, it includes: a substrate 2, and four terminal electrodes E1 to E4 embedded in the substrate 2. As described later, three conductor layers 100, 200, and 300, which are stacked via insulating layers, are embedded in the substrate 2.

[0050] Figure 2 This is a top view to illustrate the general shape of the pattern of conductor layer 100.

[0051] Conductor layer 100 is the lowest conductor layer and has a spiral coil pattern 110 and connecting patterns 121-125. The outer peripheral end 110A of the coil pattern 110 is connected to the connecting pattern 121 via a lead-out portion 113. The inner peripheral end 110B of the coil pattern 110 is connected to the connecting pattern 125. The connecting pattern 125 can be considered as part of the coil pattern 110, in which case the front end of the connecting pattern 125 constitutes the inner peripheral end of the coil pattern 110. The coil pattern 110 is wound clockwise from the outer peripheral end 110A toward the inner peripheral end 110B, while the lead-out portion 113 is not wound clockwise but extends linearly in the -X direction from the outer peripheral end 110A toward the inner peripheral end 110B. The connecting patterns 122-124 are independently provided within the conductor layer 100 without being connected to other conductor patterns.

[0052] The coil pattern 110, when viewed from above in the stacking direction (Z direction), is approximately elliptical, with the X direction as its major axis and the Y direction as its minor axis. Therefore, the inner diameter region A enclosed by the coil pattern 110 has a shape where its dimension in the X direction is larger than its dimension in the Y direction. Here, assuming a virtual line Ly passing through the center of the inner diameter region A of the coil pattern 110 and extending along the Y direction, the coil pattern 110 is divided into a section 111 located on the +X direction side when viewed from the virtual line Ly, and a section 112 located on the -X direction side when viewed from the virtual line Ly. Figure 2 As shown, in this embodiment, both the outer peripheral end 110A and the inner peripheral end 110B of the coil pattern 110 belong to interval 111. That is, both the outer peripheral end 110A and the inner peripheral end 110B of the coil pattern 110 are located on the +X direction side when viewed from the virtual line Ly. Furthermore, the circumferential position of the inner peripheral end 110B of the coil pattern 110 is further forward in the winding direction from the outer peripheral end 110A to the inner peripheral end 110B compared to the circumferential position of the outer peripheral end 110A of the coil pattern 110. As a result, the number N of coil conductors constituting interval 112 is 12 (N=12), while the number N of coil conductors constituting interval 111 is 13 (N=13), which is one more than the number of coil conductors constituting interval 112.

[0053] exist Figure 2 In the example shown, in interval 112, the number of coil conductors N is 12 (N=12) at any circumferential position. Conversely, in interval 111, the number of coil conductors N in the right-hand (clockwise) region from circumferential position R1 to circumferential position R2 is 13 (N=13), while the number of coil conductors N in other regions is 12 (N=12). Circumferential position R1 is the position of the outer circumferential end 110A of coil pattern 110. Circumferential position R2 is the position of the right-hand (clockwise) end of connecting pattern 125, corresponding to the inner circumferential end when connecting pattern 125 is considered part of coil pattern 110.

[0054] The inner diameter region A of coil pattern 110 is divided into region A1, which is located on the +X direction side when viewed from the virtual line Ly, and region A2, which is located on the -X direction side when viewed from the virtual line Ly. The entire connecting pattern 125 is located in region A1.

[0055] like Figure 2As shown, a magnetic body 3, as part of the substrate 2, is disposed in the inner diameter region A of the coil pattern 110. The magnetic body 3 is arranged such that it axially penetrates the inner diameter region A of the coil patterns 110 and 210. The magnetic body 3 is composed of a mixture of a material with a higher permeability than the insulating material such as resin constituting other parts of the substrate 2, such as ferrite powder or metallic magnetic powder, and a resin binder. The magnetic body 3 is not located in the center of the inner diameter region A of the coil pattern 110, but is disposed offset towards region A2. Figure 2 In the example shown, the virtual line Ly crosses the magnetic body 3, with a portion (most of) of the magnetic body 3 located in region A2 and the remainder located in region A1. Thus, because the magnetic body 3 is offset towards region A2, the interval 112 of the coil pattern 110 is closer to the magnetic body 3 than the interval 111 of the coil pattern 110.

[0056] More specifically, when the area of ​​the portion located in region A1 of the XY cross-section of the magnetic body 3 is set as Sa, and the area of ​​the portion located in region A2 is set as Sb, Sa < Sb. The area Sb is preferably at least twice the area Sa, and can also be at least 2.3 times. Furthermore, when the maximum dimension of the portion located in region A1 of the magnetic body 3 in the Y direction is set as La, and the maximum dimension of the portion located in region A2 is set as Lb, La < Lb. The dimension Lb is preferably at least 1.2 times the dimension La. Moreover, assuming a virtual line Lx extending along the X direction through the center of the inner diameter region A of the coil pattern 110, when the distance along the virtual line Lx between the portion of the magnetic body 3 located in region A1 and the innermost circumference of the coil pattern 110 is set as Wa, and the distance along the virtual line Lx between the portion of the magnetic body 3 located in region A2 and the innermost circumference of the coil pattern 110 is set as Wb, Wa > Wb. The distance Wa is preferably at least 1.5 times the distance Wb, and can also be at least 1.9 times. Figure 2 As shown by the dashed line, the distance Wa is defined by the distance between a portion of the connecting pattern 125, i.e., the portion located on the extension line of the innermost circumference of the coil pattern 110, and the magnetic body 3.

[0057] Figure 3 This is a rough top view of the insulating layer 10.

[0058] The insulating layer 10 is located between the conductor layer 100 and the conductor layer 200, and has openings 11-15 and 17. The openings 11-15 are respectively provided at positions that expose the connecting patterns 121-125. A magnetic body 3 is embedded in the opening 17.

[0059] Figure 4 This is a top view to illustrate the general shape of the pattern of conductor layer 200.

[0060] The conductor layer 200 has a spiral coil pattern 210 and connecting patterns 221-226. The outer peripheral end 210A of the coil pattern 210 is connected to the connecting pattern 222 via a lead-out portion 213. The inner peripheral end 210B of the coil pattern 210 is connected to the connecting pattern 226. The connecting pattern 226 can be considered as part of the coil pattern 210, in which case the front end of the connecting pattern 226 constitutes the inner peripheral end of the coil pattern 210. The coil pattern 210 is wound clockwise from the outer peripheral end 210A toward the inner peripheral end 210B, and in contrast, the lead-out portion 213 extends linearly from the connecting pattern 222 toward the outer peripheral end 210A in the +X direction. The connecting patterns 221, 223, 224, and 225 are provided independently within the conductor layer 200 without being connected to other conductor patterns. The connecting patterns 221 to 225 are connected to the connecting patterns 121 to 125 respectively through the openings 11 to 15 provided in the insulating layer 10.

[0061] The number of turns in coil pattern 210 is approximately the same as the number of turns in coil pattern 110, and each turn of coil pattern 210 overlaps with the corresponding turn of coil pattern 110 in the Z direction. In cases where the number of turns in coil pattern 110 differs from that in coil pattern 210 due to factors such as the position of the lead-out portion, it is preferable that the difference in the number of turns between coil pattern 110 and coil pattern 210 be less than 1 / 2 turn in order to ensure its function as a common-mode filter.

[0062] Here, assuming a virtual line Ly extending along the Y direction through the center of the inner diameter region of the coil pattern 210, the coil pattern 210 is divided into a section 211 located on the +X direction side when viewed from the virtual line Ly, and a section 212 located on the -X direction side when viewed from the virtual line Ly. Figure 4 As shown, in this embodiment, the outer peripheral end 210A of the coil pattern 210 is located on the virtual line Ly, and the inner peripheral end 210B of the coil pattern 210 belongs to the interval 211. That is, the inner peripheral end 210B of the coil pattern 210 is located on the +X direction side when viewed from the virtual line Ly. Furthermore, the circumferential position of the inner peripheral end 210B of the coil pattern 210 is further forward in the winding direction from the outer peripheral end 210A to the inner peripheral end 210B compared to the circumferential position of the outer peripheral end 210A of the coil pattern 210. As a result, the number N of coil conductors constituting the interval 212 is 12 (N=12), while the number N of coil conductors constituting the interval 211 is 13 (N=13), which is one more than the number of coil conductors constituting the interval 212.

[0063] exist Figure 4In the example shown, the number of coil conductors N in interval 211 is 13 (N=13) at any circumferential position, and the number of coil conductors N in interval 212 is 12 (N=12) at any circumferential position. The right-hand (clockwise) end of connecting pattern 226 is located on the virtual line Ly, which corresponds to the inner circumferential end when connecting pattern 226 is considered as part of coil pattern 210. The entirety of connecting patterns 225 and 226 is located in region A1.

[0064] The position of the magnetic body 3 in the inner diameter region of coil pattern 210 and Figure 2 The same. That is, the magnetic body 3 is offset towards region A2. As a result, the distance between the magnetic body 3 and the interval 212 of the coil pattern 210 is closer than that between the interval 211 of the coil pattern 210.

[0065] like Figure 4 As shown, the outer peripheral edge of the magnetic body 3, viewed from above in the stacking direction (Z direction), includes: a convex edge 3a located in region A2 and along the innermost circumferential turn of the coil pattern 210, and a concave edge 3b cut out in a manner that avoids the connecting pattern 226 constituting the inner peripheral end of the coil pattern 210. The concave edge 3b intersects the virtual line Ly.

[0066] Figure 5 This is a rough top view of the insulating layer 20.

[0067] The insulating layer 20 is located between the conductor layer 200 and the conductor layer 300, and has openings 21 to 27. The openings 21 to 26 are respectively provided at positions that expose the connecting patterns 221 to 226. A magnetic body 3 is embedded in the opening 27.

[0068] Figure 6 This is a top view to illustrate the general shape of the conductor layer 300 pattern.

[0069] The semiconductor layer 300 has connection patterns 321 to 326. Connection patterns 321 to 326 are connected to connection patterns 221 to 226 via openings 21 to 26 provided in the insulating layer 20, respectively. In addition, connection pattern 325 is connected to connection pattern 323 via lead-out portion 325a. Connection pattern 326 is connected to connection pattern 324 via lead-out portion 326a.

[0070] Figure 7 This is a rough top view of the insulating layer 30.

[0071] The insulating layer 30 is the uppermost insulating layer and has openings 31-34 and 37. Openings 31-34 are respectively positioned to expose the connecting patterns 321-324. A magnetic material 3 is embedded in opening 37. Furthermore, Figure 1The terminal electrodes E1 to E4 shown are connected to the connection patterns 321 to 324 via openings 31 to 34, respectively.

[0072] With this structure, the outer peripheral end of coil pattern 110 is connected to terminal electrode E1, the outer peripheral end of coil pattern 210 is connected to terminal electrode E2, the inner peripheral end of coil pattern 110 is connected to terminal electrode E3, and the inner peripheral end of coil pattern 210 is connected to terminal electrode E4. Thus, as... Figure 8 As shown, coil pattern 110 connected between terminal electrode E1 and terminal electrode E3 and coil pattern 210 connected between terminal electrode E2 and terminal electrode E4 are coupled.

[0073] Furthermore, according to the common-mode filter 1 of this embodiment, the magnetic body 3 is not disposed in the center of the inner diameter region of the coil patterns 110, 210, but is disposed offset towards region A2. Therefore, the inductance of the regions 112, 212 with fewer coil conductors is increased. That is, the difference between the inductance generated in the regions 112, 212 with fewer coil conductors and the inductance generated in the regions 111, 211 with more coil conductors is reduced. As a result, higher common-mode attenuation characteristics and lower differential insertion loss characteristics can be obtained.

[0074] Furthermore, connecting patterns 125, 225, and 226 are arranged on the region A1 side, thus effectively utilizing the inner diameter region A of the coil patterns 110 and 210. That is, the inner diameter region A of the coil patterns 110 and 210 has a shape with the X direction as its long side. The connecting patterns 125, 225, and 226 are arranged in the space on the +X direction side, which is created by offsetting the magnetic body 3 to the -X direction side. This allows the magnetic body 3 and the connecting patterns 125, 225, and 226 to be accommodated in the inner diameter region A of the coil patterns 110 and 210 without increasing the size of the coil patterns 110 and 210.

[0075] Furthermore, the planar shape of the magnetic body 3 is not simply circular or rectangular; it has a convex edge 3a in region A2 and a concave edge 3b near the connecting pattern 226. This ensures a planar distance from the connecting patterns 125, 225, and 226, and further increases the volume of the magnetic body 3. Moreover, by positioning the front end of the connecting pattern 226 approximately on the virtual line Ly, the number of turns of the coil pattern 210 is maximized. As a result, the concave edge 3b of the magnetic body 3 intersects the virtual line Ly.

[0076] Figure 9 , Figure 11 as well as Figure 13 These are approximate top views illustrating the pattern shapes of conductor layers 100A, 200A, and 300A according to the modified examples. Additionally, Figure 10 , Figure 12 as well as Figure 14 These are approximate top views of insulating layers 10A, 20A, and 30A according to the modified examples.

[0077] exist Figures 9-14 In the variant shown, in addition to having magnetic bodies 4 and 5 located in the outer region of coil patterns 110 and 210, it is similar to... Figures 2-7 The structures shown are different. Magnetic bodies 4 and 5 are another part of body 2, and can also be made of the same magnetic material as magnetic body 3. Other basic structures are the same as... Figures 2-7 Since the structures shown are the same, the same reference numerals are used to label the same elements, and repeated descriptions are omitted.

[0078] Magnetic body 4 is located in the outer region of coil patterns 110 and 210, and is located on the +X direction side of coil patterns 110 and 210. Magnetic body 5 is located in the outer region of coil patterns 110 and 210, and is located on the -X direction side of coil patterns 110 and 210. By adding such magnetic bodies 4 and 5, the inductance of coil patterns 110 and 210 can be further improved. In this embodiment, the planar shape of the base body 2 is a rectangle with the X direction as the long side and the Y direction as the short side. Therefore, the X direction side of the outer region of coil patterns 110 and 210 has more space than the Y direction side. By arranging magnetic bodies 4 and 5 in this space, the inductance can be improved.

[0079] The above describes the implementation of the technology involved in this disclosure. However, the technology involved in this disclosure is not limited to the above implementation. Various changes can be made without departing from its spirit, and these are of course included within the scope of this disclosure.

[0080] The technologies involved in this disclosure include, but are not limited to, the following structural examples.

[0081] A common-mode filter according to one aspect of the present disclosure comprises: a first coil pattern having a plurality of spiral turns wound in a spiral manner; a second coil pattern having a plurality of spiral turns wound in a spiral manner stacked on the first coil pattern via an insulating layer; and a magnetic body disposed, when viewed from a top view in a stacking direction, in an inner diameter region surrounded by the first coil pattern and the second coil pattern, the inner diameter region having a shape in which the dimension in a first direction is larger than the dimension in a second direction orthogonal to the first direction, the inner diameter region comprising: a first region located on one side in the first direction when viewed from a virtual line passing through the center of the inner diameter region and extending along the second direction; and a second region located on the other side in the first direction when viewed from the virtual line, the first coil pattern being surrounded by the first coil pattern. The second coil pattern includes: a first section located on one side of a first direction when viewed from a virtual line; and a second section located on the other side of the first direction when viewed from a virtual line. The second coil pattern includes: a third section located on one side of the first direction when viewed from a virtual line; and a fourth section located on the other side of the first direction when viewed from a virtual line. The number of coil conductors constituting the first section is one more in at least a portion of the circumferential positions than the number of coil conductors constituting the second section in at least a portion of the circumferential positions. The number of coil conductors constituting the third section is one more in at least a portion of the circumferential positions than the number of coil conductors constituting the fourth section in at least a portion of the circumferential positions. The magnetic body is disposed offset towards the second region side.

[0082] In the aforementioned common-mode filter, the inner circumferential ends of both the first and second coil patterns can be located in the first region. This ensures the distance between the inner circumferential ends of the first and second coil patterns and the plane of the magnetic material, and further increases the volume of the magnetic material.

[0083] In the aforementioned common-mode filter, the outer peripheral edge of the magnetic body, viewed from above in the stacking direction, may include: a convex edge located in the second region and along the innermost circumferential turns of the first and second coil patterns, and a concave edge cut to avoid the inner circumferential end of the second coil pattern. This ensures a safe distance between the inner circumferential end of the second coil pattern and the planar distance of the magnetic body, further increasing the volume of the magnetic body. In this case, the concave edge may intersect with a virtual line. This increases the number of turns of the second coil pattern.

Claims

1. A common-mode filter, wherein, have: The first coil pattern has multiple spiral turns. The second coil pattern is stacked on top of the first coil pattern via an insulating layer and wound in a spiral shape multiple turns; as well as A magnetic material, when viewed from above in the stacking direction, is disposed in the inner diameter region surrounded by the first coil pattern and the second coil pattern. The inner diameter region has a shape in which the dimension in the first direction is larger than the dimension in the second direction, which is orthogonal to the first direction. The inner diameter region includes: a first region located on one side in the first direction when viewed from the center of the inner diameter region by a virtual line extending along the second direction; and a second region located on the other side in the first direction when viewed from the virtual line. The first coil pattern includes: a first interval located on one side in the first direction when viewed from the virtual line; and a second interval located on the other side in the first direction when viewed from the virtual line. The second coil pattern includes: a third section located on one side in the first direction when viewed from the virtual line; and a fourth section located on the other side in the first direction when viewed from the virtual line. The coil conductors constituting the first interval have one more conductor in at least a portion of their circumferential positions than the coil conductors constituting the second interval in at least a portion of their circumferential positions. The coil conductors constituting the third interval have one more conductor in at least a portion of their circumferential positions than the coil conductors constituting the fourth interval in at least a portion of their circumferential positions. The magnetic material is offset toward the second region.

2. The common-mode filter according to claim 1, wherein, The inner circumferential ends of both the first coil pattern and the second coil pattern are located in the first region.

3. The common-mode filter according to claim 2, wherein, The outer peripheral edge of the magnet, viewed from above in the stacking direction, includes: a convex edge located in the second region and along the innermost circumferential turns of the first and second coil patterns, and a concave edge cut out in a manner that avoids the inner peripheral end of the second coil pattern.

4. The common-mode filter according to claim 3, wherein, The concave edge intersects with the virtual line.

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