Common mode noise filter

Abstract

A common mode noise filter (1) according to an embodiment comprises an element body (2), a first conductor part (3), and a second conductor part (4). The first conductor part (3) and the second conductor part (4) are provided inside the element body (2), and are arranged in the up-down direction. The first conductor part (3) has a first spiral conductor (31) and a first lead-out conductor (32). The second conductor part (4) has a second spiral conductor (41) and a second lead-out conductor (42). The second spiral conductor (41) or the second lead-out conductor (42) is provided between the first spiral conductor (31) and the first lead-out conductor (32) in the up-down direction.

Description

Common Mode Noise Filter

[0001] The present disclosure relates generally to a common mode noise filter, and more particularly to a common mode noise filter having multiple conductor portions.

[0002] Patent Document 1 discloses a common mode noise filter including stacked first and second spiral conductors, first and second terminal electrodes, first and second lead conductors, and multiple resin insulation layers. The first lead conductor connects the inner peripheral end of the first spiral conductor to the first terminal electrode. The second lead conductor connects the inner peripheral end of the second spiral conductor to the second terminal electrode. Multiple resin insulation layers are provided between the first and second spiral conductors. The first and second lead conductors are formed on different resin insulation layers from the multiple resin insulation layers.

[0003] JP 2009-33033 A

[0004] In the above-described common-mode noise filter, when a high voltage is applied to the first spiral conductor and the first lead conductor, the following problem may occur: The electric field strength between the outermost periphery of the first spiral conductor and the first lead conductor increases, which may cause cracks or fissures to form between the outermost periphery of the first spiral conductor and the first lead conductor. In other words, the above-described conventional common-mode noise filter may have reduced resistance to high voltages.

[0005] The present disclosure provides a common mode noise filter that can suppress a decrease in resistance to high voltages.

[0006] A common mode noise filter according to one aspect of the present disclosure includes an element body, a first conductor portion, and a second conductor portion. The first conductor portion and the second conductor portion are provided inside the element body and are aligned in the vertical direction. The first conductor portion has a first spiral conductor and a first lead conductor. The first spiral conductor extends in a spiral shape. The first lead conductor is provided on a different plane from the first spiral conductor in the vertical direction, and both ends of the first spiral conductor are led out to the outer surface of the element body. The second conductor portion has a second spiral conductor and a second lead conductor. The second spiral conductor extends in a spiral shape. The second lead conductor is provided on a different plane from the second spiral conductor in the vertical direction, and both ends of the second spiral conductor are led out to the outer surface of the element body. A second spiral conductor or a second lead conductor is provided between the first spiral conductor and the first lead conductor in the vertical direction.

[0007] A common mode noise filter according to an aspect of the present disclosure has an advantage in that it is possible to suppress a decrease in resistance to high voltages.

[0008] FIG. 1 is an exploded perspective view of the common mode noise filter according to this embodiment. FIG. 2A is a plan view of the common mode noise filter according to the present embodiment. FIG. 2B is a plan view of the common mode noise filter according to the present embodiment. FIG. 2C is a plan view of the common mode noise filter according to the present embodiment. FIG. 2D is a plan view of the common mode noise filter according to the present embodiment. FIG. 3 is a side view of the common mode noise filter according to the present embodiment. FIG. 4 is a cross-sectional view of a main portion of the common mode noise filter according to the present embodiment, taken along line X1-X1 in FIGS. 2A to 2D. FIG. 5 is a cross-sectional view of a main portion of the common mode noise filter according to the present embodiment, taken along line X2-X2 in FIGS. 2A to 2D. FIG. 6 is a graph showing the communication signal attenuation characteristics of the common mode noise filter according to the present embodiment. FIG. 7 is a graph showing the common mode noise attenuation characteristics of the common mode noise filter according to the present embodiment. FIG. 8 is a cross-sectional view of a main portion of a common mode noise filter according to a first modified example. FIG. 9 is a cross-sectional view of a main portion of a common mode noise filter according to a second modified example.

[0009] The embodiments and modifications described below are merely examples of the present disclosure. The present disclosure is not limited to the embodiments and modifications, and various modifications other than these embodiments and modifications are possible depending on the design, etc., as long as they do not deviate from the technical concept of the present disclosure. The drawings described in the following embodiments and modifications are schematic drawings, and the ratios of the sizes and thicknesses of the components in the drawings do not necessarily reflect the actual dimensional ratios.

[0010] (Embodiment) (1) Overview An overview of the common-mode noise filter 1 according to this embodiment will be described below with reference to FIGS. 1 to 3. FIG. 1 is an exploded perspective view of the common-mode noise filter 1 according to this embodiment. FIGS. 2A to 2D are plan views of the common-mode noise filter 1. FIG. 3 is a side view of the common-mode noise filter 1. Note that the terms "upper" and "lower" used in this disclosure merely represent the relative positional relationships of the components of the common-mode noise filter 1 and are not intended to limit the direction in which the common-mode noise filter 1 is used. The common-mode noise filter 1 may be used in any orientation in which "lower" used in this disclosure refers to, for example, top, front, rear, left, or right. Although arrows representing up / down, left / right, and front / back are shown in FIGS. 1 and 2A to 2D, these arrows are merely used for explanatory purposes and do not represent any physical entity.

[0011] The common mode noise filter 1 according to this embodiment passes differential mode components of a signal while attenuating common mode noise components. The common mode noise filter 1 is mounted on a circuit board or electronic component of an electronic device.

[0012] 1 and 3, the common mode noise filter 1 includes an element body 2, a first conductor 3, and a second conductor 4. The first conductor 3 and the second conductor 4 are provided inside the element body 2. The first conductor 3 and the second conductor 4 are aligned in the vertical direction.

[0013] The first conductor section 3 has a first spiral conductor 31 and a first lead conductor 32. The first spiral conductor 31 extends in a spiral shape. The first lead conductor 32 is provided on a different plane from the first spiral conductor 31 in the vertical direction, and both ends of the first spiral conductor 31 are extended to the outer surface of the element body 2. Similarly, the second conductor section 4 has a second spiral conductor 41 and a second lead conductor 42. The second spiral conductor 41 extends in a spiral shape. The second lead conductor 42 is provided on a different plane from the second spiral conductor 41 in the vertical direction, and both ends of the second spiral conductor 41 are extended to the outer surface of the element body 2. In the common mode noise filter 1 of this embodiment, the second spiral conductor 41 is provided between the first spiral conductor 31 and the first lead conductor 32 in the vertical direction.

[0014] A common-mode noise filter (hereinafter referred to as a "common-mode noise filter of the comparative example") that does not have either a second spiral conductor or two second lead conductors between the first spiral conductor and the two first lead conductors in the vertical direction has the following problem. Specifically, in the common-mode noise filter of the comparative example, when a high voltage is applied to the first spiral conductor and the two first lead conductors, a voltage drop occurs depending on the number of turns of the first spiral conductor. This increases the electric field strength between the outermost periphery of the first spiral conductor and the first lead conductor with the longest conduction distance from the outermost periphery of the two first lead conductors. As a result, in the common-mode noise filter of the comparative example, cracks may occur between the outermost periphery of the first spiral conductor and the first lead conductor. In short, the common-mode noise filter of the comparative example may have reduced resistance to high voltages.

[0015] However, in the common-mode noise filter 1 of this embodiment, the second spiral conductor 41 is provided between the first spiral conductor 31 and the first lead conductor 32 in the up-down direction. This increases the distance between the first spiral conductor 31 and the first lead conductor 32 in the up-down direction. Therefore, when a high voltage is applied to the first spiral conductor 31 and the first lead conductor 32, it is possible to prevent the electric field strength between the outermost periphery 315 (see FIG. 2B ) of the first spiral conductor 31 and the first lead conductor 32 from increasing. As a result, the common-mode noise filter 1 of this embodiment has the advantage of being able to prevent cracks from occurring between the first spiral conductor 31 and the first lead conductor 32.

[0016] As described above, the common mode noise filter 1 of this embodiment has the advantage of being able to suppress a decrease in resistance to high voltages.

[0017] (2) Detailed Configuration (2-1) Overall Configuration The detailed configuration of the common mode noise filter 1 will be described below with reference to FIGS.

[0018] As shown in FIGS. 1 and 3, the common mode noise filter 1 includes an element body 2, a first conductor portion 3, a second conductor portion 4, vias B1, B2, B3, and B4, and a magnetic member 5.

[0019] As shown in Fig. 1 , the first conductor section 3 has a first spiral conductor 31 and a first lead conductor 32. As shown in Fig. 2D , the first conductor section 3 has two first lead conductors 321 and 322 as the first lead conductor 32. As shown in Fig. 3 , the first lead conductor 321 and the first spiral conductor 31 are electrically connected via a via B1. Furthermore, the first lead conductor 322 and the first spiral conductor 31 are electrically connected via a via B2. In short, the first lead conductor 321 and the first lead conductor 322 are electrically connected via the via B1, the first spiral conductor 31, and the via B2.

[0020] Similarly, as shown in Fig. 1, the second conductor section 4 has a second spiral conductor 41 and a second lead conductor 42. As shown in Fig. 2A, the second conductor section 4 has two second lead conductors 421, 422 as the second lead conductor 42. As shown in Fig. 3, the second lead conductor 421 and the second spiral conductor 41 are electrically connected via via B3. Furthermore, the second lead conductor 422 and the second spiral conductor 41 are electrically connected via via B4. In short, the second lead conductor 421 and the second lead conductor 422 are electrically connected via via B3, the second spiral conductor 41, and via B4.

[0021] One of the first lead conductors 321 and 322 is used as a first input terminal, and the other is used as a first output terminal. One of the second lead conductors 421 and 422 is used as a second input terminal, and the other is used as a second output terminal. That is, the common mode noise filter 1 has a first input terminal, a second input terminal, a first output terminal, and a second output terminal. The common mode noise filter 1 removes common mode noise from a differential signal input via the first input terminal and the second input terminal, and outputs the signal from the first output terminal and the second output terminal.

[0022] (2-2) Element Body As shown in Figures 1 and 3, the element body 2 includes a plurality of (15 in Figures 1 and 3) insulator layers 20. The plurality of insulator layers 20 are stacked in the vertical direction.

[0023] The multiple insulator layers 20 include insulator layers 21, 22, 23, 24, 25, 26, 27, 28, 29, 2a, 2b, 2c, 2d, 2e, and 2f. The multiple insulator layers 20 are stacked in the following order from top to bottom: insulator layers 2a, 26, 2b, 27, 2c, 21, 22, 23, 24, 25, 2d, 28, 2e, 29, and 2f. Adjacent insulator layers 20 may be integrated to the extent that the boundaries between the layers are not visible.

[0024] The insulator layers 21 to 29 are non-magnetic layers. The non-magnetic layers include, for example, glass ceramic as a material. As an example, in FIG. 3, the thickness of the insulator layers 26 to 29 is greater than the thickness of the insulator layers 21 to 25. In this disclosure, "thickness" refers to the dimension in the vertical direction.

[0025] The insulating layers 2a to 2f are magnetic layers. The magnetic layers contain, for example, ferrite. For example, the thickness of the magnetic layers (insulating layers 2a to 2f) is greater than the thickness of the non-magnetic layers (insulating layers 21 to 29).

[0026] In this embodiment, as shown in Figures 1 and 3, the second extraction conductors 421, 422 are provided on a first plane inside the element body 2. The first spiral conductor 31 is provided on a second plane inside the element body 2. The second spiral conductor 41 is provided on a third plane inside the element body 2. The first extraction conductors 321, 322 are provided on a fourth plane inside the element body 2. The first to fourth planes are aligned in the vertical direction and are parallel to each other. Note that "parallel" in the present disclosure does not necessarily mean parallel in the strict sense, but also includes cases where there is an error of several degrees.

[0027] In this embodiment, the second lead conductors 421, 422 are provided between the insulator layer 21 and the insulator layer 22. The first spiral conductor 31 is provided between the insulator layer 22 and the insulator layer 23. The second spiral conductor 41 is provided between the insulator layer 23 and the insulator layer 24. The first lead conductors 321, 322 are provided between the insulator layer 24 and the insulator layer 25.

[0028] (2-3) First Spiral Conductor First, the first spiral conductor 31 will be described. When viewed from the top-bottom direction, the first spiral conductor 31 has a spiral shape. That is, the first spiral conductor 31 is a conductor formed in a spiral shape. More specifically, the first spiral conductor 31 has a shape in which a conductor is wound multiple times around an oval. The length of the area occupied by the first spiral conductor 31 in the front-to-rear direction is shorter than the length of the area occupied by the first spiral conductor 31 in the left-to-right direction. In the illustrated example, the first spiral conductor 31 has five turns, but the number of turns is not particularly limited. The first spiral conductor 31 is made of a conductive material such as silver.

[0029] 2B , the first spiral conductor 31 includes a first turn portion 311, a second turn portion 312, a third turn portion 313, a fourth turn portion 314, and a fifth turn portion 315. Of the portions 311 to 315, the first turn portion 311 is located on the innermost side, and the fifth turn portion 315 is located on the outermost side. In other words, the fifth turn portion 315 is the outermost periphery of the first spiral conductor 31.

[0030] The first conductor portion 3 further includes a via pad 33 electrically connected to the via B1 and a via pad 34 electrically connected to the via B2. Each of the via pads 33, 34 is provided on a second plane inside the element body 2, i.e., on the same plane as the first spiral conductor 31 (on the same plane). Each of the via pads 33, 34 is provided between the insulator layer 22 and the insulator layer 23. The via pad 33 is provided on the outside of the first spiral conductor 31, and the via pad 34 is provided on the inside of the first spiral conductor 31. When viewed from above and below, each of the via pads 33, 34 has a rectangular shape with rounded corners. The via pads 33, 34 are made of a conductive material such as silver.

[0031] A first end 316 on the fifth turn portion 315 (outermost periphery) side of the first spiral conductor 31 is seamlessly connected to the via pad 33. That is, the via pad 33 is a conductive via pad electrically connected to the via B1 and the first spiral conductor 31.

[0032] Similarly, the second end 317 of the first spiral conductor 31 on the first turn portion 311 side is seamlessly connected to the via pad 34. That is, the via pad 34 is a conductive via pad electrically connected to the via B2 and the first spiral conductor 31.

[0033] (2-4) First Lead Conductor Next, the first lead conductors 321 and 322 will be described. The first lead conductor 321 leads the first end 316 of the first spiral conductor 31 to the outer surface of the element body 2. Similarly, the first lead conductor 322 leads the second end 317 of the first spiral conductor 31 to the outer surface of the element body 2. As shown in Fig. 2D, each of the first lead conductors 321 and 322 is arranged on the outer edge of the element body 2. In this embodiment, the first lead conductors 321 and 322 are aligned in the left-right direction.

[0034] The first conductor portion 3 further includes a via pad 35 electrically connected to the via B1 and a via pad 36 electrically connected to the via B2. Each of the via pads 35, 36 is provided on a fourth plane within the element body 2, i.e., the same plane (coplanar) as the first lead conductors 321, 322. Each of the via pads 35, 36 is provided between the insulator layer 24 and the insulator layer 25. When viewed from the top-bottom direction, the via pad 35 is provided at a position overlapping with the via pad 33, and the via pad 36 is provided at a position overlapping with the via pad 34. When viewed from the top-bottom direction, each of the via pads 35, 36 has a rectangular shape with rounded corners. The via pads 35, 36 are made of a conductive material such as silver.

[0035] 2D , the first extraction conductor 321 of this embodiment has a rectangular shape with rounded corners when viewed from the top and bottom. A portion of the lower edge of the first extraction conductor 321 is seamlessly connected to the via pad 35. That is, the via pad 35 is a current-carrying via pad electrically connected to the via B1 and the first extraction conductor 321. As described above, the first extraction conductor 321 is electrically connected to the fifth turn portion 315 (the outermost periphery of the first spiral conductor 31) through the via pad 35, the via B1, and the via pad 33.

[0036] On the other hand, the first extraction conductor 322 of this embodiment has a first portion 323 and a second portion 324. When viewed from the top-bottom direction, the first portion 323 has a rectangular shape with rounded corners. The second portion 324 extends from a part of the lower edge of the first portion 323 and is seamlessly connected to the via pad 36. In other words, the via pad 36 is a current-carrying via pad electrically connected to the via B2 and the first extraction conductor 322. As described above, the first extraction conductor 322 is electrically connected to the first turn portion 311 via the via pad 36, the via B2, and the via pad 34.

[0037] In other words, the first lead conductor 321 has a shorter conduction distance from the outermost periphery 315 of the first spiral conductor 31 than the first lead conductor 322. In other words, the first lead conductor 322 has a longer conduction distance from the outermost periphery 315 of the first spiral conductor 31 than the first lead conductor 321.

[0038] In the common-mode noise filter of the comparative example, when a high voltage is applied to the first spiral conductor and the two first lead conductors, a voltage drop occurs according to the number of turns in the first spiral conductor, which increases the electric field strength between the outermost periphery of the first spiral conductor and the first lead conductor that is the longest conductive distance from the outermost periphery, and this can cause fissures or cracks to form between the outermost periphery of the first spiral conductor and the first lead conductor.

[0039] However, in the common-mode noise filter 1 of this embodiment, the second spiral conductor 41 is provided between the first spiral conductor 31 and the first lead conductors 321, 322 in the vertical direction. With this configuration, the vertical distance between the first spiral conductor 31 and the first lead conductor 32 is increased. Therefore, when a high voltage is applied to the first spiral conductor 31 and the first lead conductors 321, 322, it is possible to prevent an increase in the electric field strength between the outermost periphery 315 of the first spiral conductor 31 and the first lead conductor 322, which is the first lead conductor 321, 322 that has a long conduction distance from the outermost periphery 315. As a result, the common-mode noise filter 1 of this embodiment has the advantage of being able to prevent cracks from occurring between the outermost periphery 315 of the first spiral conductor 31 and the first lead conductor 322. In other words, the common-mode noise filter 1 of this embodiment has the advantage of being able to further prevent a decrease in resistance to high voltages.

[0040] (2-5) Second Spiral Conductor The second spiral conductor 41 will now be described. When viewed from the top-bottom direction, the second spiral conductor 41 has a spiral shape. That is, the second spiral conductor 41 is a conductor formed in a spiral shape. More specifically, the second spiral conductor 41 has a shape in which a conductor is wound multiple times around an oval. The length of the area occupied by the second spiral conductor 41 in the front-to-rear direction is shorter than the length of the area occupied by the second spiral conductor 41 in the left-to-right direction. In the illustrated example, the number of turns in the second spiral conductor 41 is five, but the number of turns is not particularly limited. The second spiral conductor 41 is made of a conductive material such as silver.

[0041] 2C , the second spiral conductor 41 includes a first turn portion 411, a second turn portion 412, a third turn portion 413, a fourth turn portion 414, and a fifth turn portion 415. Of the portions 411 to 415, the first turn portion 411 is located on the innermost side, and the fifth turn portion 415 is located on the outermost side. In other words, the fifth turn portion 415 is the outermost periphery of the second spiral conductor 41.

[0042] As shown in FIG. 2C , the second conductor portion 4 further includes a via pad 43 electrically connected to the via B3 and a via pad 44 electrically connected to the via B4. Each of the via pads 43 and 44 is provided on a third plane inside the element body 2, i.e., on the same plane as the second spiral conductor 41 (on the same plane). Each of the via pads 43 and 44 is provided between the insulator layer 23 and the insulator layer 24. The via pad 43 is provided on the outside of the second spiral conductor 41, and the via pad 44 is provided on the inside of the second spiral conductor 41. When viewed from the top and bottom, each of the via pads 43 and 44 has a rectangular shape with rounded corners. The via pads 43 and 44 are made of a conductive material such as silver.

[0043] A first end 416 on the fifth turn portion 415 (outermost periphery) side of the second spiral conductor 41 is seamlessly connected to the via pad 43. The via pad 43 is a conductive via pad electrically connected to the via B3 and the second spiral conductor 41.

[0044] Similarly, a second end 417 of the second spiral conductor 41 on the first turn portion 411 side is seamlessly connected to the via pad 44. The via pad 44 is a conductive via pad electrically connected to the via B4 and the second spiral conductor 41.

[0045] (2-5) Second Lead Conductor Next, the second lead conductors 421, 422 will be described. The second lead conductor 421 leads the first end 416 of the second spiral conductor 41 to the outer surface of the element body 2. Similarly, the second lead conductor 422 leads the second end 417 of the second spiral conductor 41 to the outer surface of the element body 2. When viewed from the top-bottom direction, each of the second lead conductors 421, 422 is provided outside the second spiral conductor 41. More specifically, each of the second lead conductors 421, 422 is arranged on the outer edge of the element body 2. The second lead conductors 421, 422 of this embodiment are aligned in the left-right direction, as shown in FIG. 2A .

[0046] The second conductor portion 4 further includes a via pad 45 electrically connected to the via B3 and a via pad 46 electrically connected to the via B4. Each of the via pads 45, 46 is provided on a first plane within the element body 2, i.e., on the same plane (coplanar) as the second lead conductors 421, 422. Each of the via pads 45, 46 is provided between the insulator layer 21 and the insulator layer 22. When viewed from the top-bottom direction, the via pad 45 is provided at a position overlapping with the via pad 43, and the via pad 46 is provided at a position overlapping with the via pad 44. When viewed from the top-bottom direction, each of the via pads 45, 46 has a rectangular shape with rounded corners. The via pads 45, 46 are made of a conductive material such as silver.

[0047] 2A , the second extraction conductor 421 of this embodiment has a rectangular shape with rounded corners when viewed from the top and bottom. A portion of the upper edge of the second extraction conductor 421 is seamlessly connected to the via pad 45. The via pad 45 is a current-carrying via pad electrically connected to the via B3 and the second extraction conductor 421. As described above, the second extraction conductor 421 is electrically connected to the fifth turn portion 415 (the outermost periphery of the second spiral conductor 41) through the via pad 45, the via B3, and the via pad 43.

[0048] On the other hand, the second extraction conductor 422 of this embodiment has a first portion 423 and a second portion 424. When viewed from the top-bottom direction, the first portion 423 has a rectangular shape with rounded corners. The second portion 424 extends from a part of the upper edge of the first portion 423 and is seamlessly connected to the via pad 46. In other words, the via pad 46 is a current-carrying via pad electrically connected to the via B4 and the second extraction conductor 422. As described above, the second extraction conductor 422 is electrically connected to the first turn portion 411 via the via pad 46, the via B4, and the via pad 44.

[0049] In other words, the second lead conductor 421 has a shorter conductive distance from the outermost periphery 415 of the second spiral conductor 41 than the second lead conductor 422. In other words, the second lead conductor 422 has a longer conductive distance from the outermost periphery 415 of the second spiral conductor 41 than the second lead conductor 421.

[0050] In the common-mode noise filter of the comparative example, when a high voltage is applied to the second spiral conductor and the two second lead conductors, a voltage drop occurs according to the number of turns in the second spiral conductor, which increases the electric field strength between the outermost periphery of the second spiral conductor and the second lead conductor that is the longest conductive distance from the outermost periphery, and this can cause cracks to form between the outermost periphery of the second spiral conductor and the second lead conductor.

[0051] However, in the common-mode noise filter 1 of this embodiment, the first spiral conductor 31 is provided between the second spiral conductor 41 and the second lead conductors 421, 422 in the vertical direction. With this configuration, the vertical distance between the second spiral conductor 41 and the second lead conductors 421, 422 is increased. Therefore, when a high voltage is applied to the second spiral conductor 41 and the second lead conductors 421, 422, it is possible to prevent an increase in the electric field strength between the outermost periphery 415 of the second spiral conductor 41 and the second lead conductor 422, which is the second lead conductor 421, 422 that has a long conduction distance from the outermost periphery 415. As a result, the common-mode noise filter 1 of this embodiment has the effect of preventing cracks from occurring between the outermost periphery 415 of the second spiral conductor 41 and the second lead conductor 422. That is, the common-mode noise filter 1 of this embodiment has the advantage of further preventing a decrease in resistance to high voltages.

[0052] (2-6) Vias Each of the vias B1, B2, B3, and B4 has a length in the vertical direction as shown in Fig. 3. Each of the vias B1, B2, B3, and B4 has a cylindrical shape with its axial direction extending in the vertical direction.

[0053] The via B1 electrically connects the via pad 33 and the via pad 35. That is, the via B1 electrically connects the first spiral conductor 31 and the first lead conductor 321 through the via pad 33 and the via pad 35. Here, the insulator layers 23 and 24 are disposed between the first spiral conductor 31 and the first lead conductor 321. As shown in FIGS. 2C and 3 , the via B1 penetrates the insulator layers 23 and 24, thereby electrically connecting the first spiral conductor 31 and the first lead conductor 321 through the via pad 33 and the via pad 35.

[0054] Similarly, via B2 electrically connects via pad 34 and via pad 36. That is, via B2 electrically connects first spiral conductor 31 and first lead conductor 322 through via pad 34 and via pad 36. Here, insulator layers 23 and 24 are disposed between first spiral conductor 31 and first lead conductor 322. As shown in FIGS. 2C and 3 , via B2 penetrates through insulator layers 23 and 24, thereby electrically connecting first spiral conductor 31 and first lead conductor 322 through via pad 34 and via pad 36.

[0055] Furthermore, the via B3 electrically connects the via pad 43 and the via pad 45. That is, the via B3 electrically connects the second spiral conductor 41 and the second lead conductor 421 through the via pad 43 and the via pad 45. Here, the insulator layers 22 and 23 are disposed between the second spiral conductor 41 and the second lead conductor 421. As shown in FIGS. 2B and 3 , the via B3 penetrates the insulator layers 22 and 23, thereby electrically connecting the second spiral conductor 41 and the second lead conductor 421 through the via pad 43 and the via pad 45.

[0056] Similarly, via B4 electrically connects via pad 44 and via pad 46. That is, via B4 electrically connects second spiral conductor 41 and second lead conductor 422 through via pad 44 and via pad 46. Here, insulator layers 22 and 23 are disposed between second spiral conductor 41 and second lead conductor 422. As shown in FIGS. 2B and 3 , via B4 penetrates insulator layers 22 and 23, thereby electrically connecting second spiral conductor 41 and second lead conductor 422 through via pad 44 and via pad 46.

[0057] (2-7) Magnetic Member A magnetic member 5 is provided in the central portion of the first spiral conductor 31 and the second spiral conductor 41. As shown in Figures 1 and 3, the magnetic member 5 in this embodiment has a cylindrical shape with its axial direction extending in the vertical direction. The magnetic member 5 is made of a magnetic material such as ferrite. For this reason, the magnetic member 5 is also called a ferrite via.

[0058] By providing the magnetic member 5 in the central portion of the first spiral conductor 31 and the second spiral conductor 41, the common mode noise filter 1 has the advantage of improving its performance in attenuating common mode noise components.

[0059] In this embodiment, as shown in FIG. 3, the upper end of the magnetic member 5 is connected to the insulating layer 2c, and the lower end of the magnetic member 5 is connected to the insulating layer 2d.

[0060] (2-8) Positional Relationship Between the First Conductor Portion and the Second Conductor Portion Here, attention will be paid to the positional relationship between the first conductor portion 3 and the second conductor portion 4. Fig. 4 is a cross-sectional view of a main portion of the common mode noise filter 1 taken along line X1-X1 in Figs. 2A to 2D. Fig. 5 is a cross-sectional view of a main portion of the common mode noise filter 1 taken along line X2-X2 in Figs. 2A to 2D.

[0061] In this embodiment, as shown in Fig. 4 , the first distance D1 and the second distance D2 are the same. The first distance D1 is the distance in the up-down direction between the first spiral conductor 31 of the first conductor portion 3 and the second lead conductor 422 of the second conductor portion 4. The second distance D2 is the distance in the up-down direction between the first spiral conductor 31 of the first conductor portion 3 and the second spiral conductor 41 of the second conductor portion 4. More specifically, the first distance D1 here is the distance in the up-down direction between the upper surface of the outermost periphery 315 of the first spiral conductor 31 of the first conductor portion 3 and the lower surface of the second lead conductor 422 of the second conductor portion 4. Similarly, the second distance D2 here is the distance in the up-down direction between the lower surface of the outermost periphery 315 of the first spiral conductor 31 of the first conductor portion 3 and the upper surface of the outermost periphery 415 of the second spiral conductor 41 of the second conductor portion 4. In this disclosure, "being the same" is not limited to being completely the same, but also includes being different to the extent that it does not cause practical problems. For example, if the difference between the two distances is within 5% of either value, they may be considered to be "the same" and the present disclosure may be applied.

[0062] 5 , the second distance D2 is equal to a third distance D3, which is the distance in the vertical direction between the second spiral conductor 41 of the second conductor portion 4 and the first lead conductor 322 of the first conductor portion 3. More specifically, the third distance D3 here is the distance in the vertical direction between the lower surface of the outermost periphery 415 of the second spiral conductor 41 of the second conductor portion 4 and the upper surface of the first lead conductor 322 of the first conductor portion 3.

[0063] As described above, in this embodiment, the first distance D1 (see FIG. 4 ), the second distance D2 (see FIGS. 4 and 5 ), and the third distance D3 (see FIG. 5 ) are the same. With this configuration, when a high voltage is applied to the first spiral conductor 31 and the first lead conductors 321, 322, it is possible to efficiently prevent an increase in electric field strength between the outermost periphery 315 of the first spiral conductor 31 and the first lead conductor 322, which is the first lead conductor 321, 322 that has a long conduction distance from the outermost periphery 315. As a result, the common-mode noise filter 1 has the effect of efficiently preventing cracks from occurring between the outermost periphery 315 of the first spiral conductor 31 and the first lead conductor 322. Similarly, when a high voltage is applied to the second spiral conductor 41 and the second lead conductors 421, 422, the common mode noise filter 1 has the effect of efficiently preventing cracks from occurring between the outermost periphery 415 of the second spiral conductor 41 and the second lead conductor 422, of the second lead conductors 421, 422, which has the longest conductive distance from the outermost periphery 415. As described above, the common mode noise filter 1 has the advantage of efficiently preventing a decrease in resistance to high voltages.

[0064] (2-9) Performance Comparison Next, attention will be focused on the results of a comparison between the performance of the common mode noise filter 1 of this embodiment and the performance of a common mode noise filter of a comparative example. Fig. 6 is a graph showing the communication signal attenuation characteristics of the common mode noise filter 1. Fig. 7 is a graph showing the common mode noise attenuation characteristics of the common mode noise filter 1.

[0065] Graph G11, shown by a solid line in FIG. 6, is a graph showing the communication signal attenuation characteristics of the common-mode noise filter 1 of this embodiment. On the other hand, graph G21, shown by a dashed line in FIG. 6, is a graph showing the communication signal attenuation characteristics of the common-mode noise filter of the comparative example. In this disclosure, the "communication signal attenuation characteristics" refer to the attenuation characteristics for a communication signal (e.g., an input differential signal) and indicate the degree to which the communication signal is attenuated depending on the frequency. Graphs G11 and G21 in FIG. 6 are approximately identical in the frequency band from 1 to 10,000 MHz. In other words, the common-mode noise filter 1 of this embodiment can suppress the attenuation of differential mode components that it passes to approximately the same level as the common-mode noise filter of the comparative example. In short, the communication signal attenuation characteristics of the common-mode noise filter 1 of this embodiment have performance equivalent to that of the common-mode noise filter of the comparative example.

[0066] Furthermore, graph G12, shown by a solid line in FIG. 7, is a graph showing the common-mode noise attenuation characteristics of the common-mode noise filter 1 of this embodiment. Meanwhile, graph G22, shown by a dashed line in FIG. 7, is a graph showing the common-mode noise attenuation characteristics of the common-mode noise filter of the comparative example. In this disclosure, the "common-mode noise attenuation characteristics" refer to the attenuation characteristics for common-mode noise components, and are characteristics that indicate the degree to which common-mode noise components are attenuated depending on frequency. Graphs G12 and G22 in FIG. 7 are approximately identical in the frequency band of 1 to 10,000 MHz. Therefore, the common-mode noise filter 1 of this embodiment can attenuate common-mode noise components to the same extent as the common-mode noise filter of the comparative example. In other words, as shown in FIG. 7, the common-mode noise attenuation characteristics of the common-mode noise filter 1 of this embodiment and the common-mode noise attenuation characteristics of the comparative example have equivalent performance.

[0067] As described above, the common-mode noise filter 1 of this embodiment has the advantage of being able to suppress a decrease in resistance to high voltage while maintaining performance (communication signal attenuation characteristics and common-mode noise attenuation characteristics) equivalent to that of the common-mode noise filter of the comparative example.

[0068] (3) Advantages In the common mode noise filter 1 according to this embodiment, the second spiral conductor 41 is provided between the first spiral conductor 31 and the first lead conductors 321 and 322 in the vertical direction.

[0069] This increases the vertical distance between the first spiral conductor 31 and the first lead conductors 321, 322. Therefore, when a high voltage is applied to the first spiral conductor 31 and the first lead conductors 321, 322, it is possible to prevent an increase in electric field strength between the outermost periphery 315 of the first spiral conductor 31 and the first lead conductor 322, which is the first lead conductor 321, 322 that has a long conduction distance from the outermost periphery 315. As a result, the common mode noise filter 1 has the effect of preventing cracks from occurring between the first spiral conductor 31 and the first lead conductor 32. In other words, the common mode noise filter 1 of this embodiment has the advantage of preventing a decrease in resistance to high voltages.

[0070] Furthermore, in the common mode noise filter 1 of this embodiment, there is no need to increase the thickness of the insulator layers 21 to 25 in order to suppress a decrease in resistance to high voltages. Therefore, the common mode noise filter 1 of this embodiment has the advantage of being able to suppress a decrease in resistance to high voltages while maintaining performance (communication signal attenuation characteristics and common mode noise attenuation characteristics) equivalent to that of the common mode noise filter of the comparative example.

[0071] In the common mode noise filter 1 according to this embodiment, the second spiral conductor 41 is provided between the first spiral conductor 31 and the first lead conductors 321 and 322 in the vertical direction. In addition, the first spiral conductor 31 is provided between the second spiral conductor 41 and the second lead conductors 421 and 422 in the vertical direction.

[0072] This advantageously prevents cracks from occurring between the first spiral conductor 31 and the first lead conductor 32 when a high voltage is applied to the first spiral conductor 31 and the first lead conductors 321 and 322. Furthermore, the common mode noise filter 1 advantageously prevents cracks from occurring between the outermost periphery 415 of the second spiral conductor 41 and the second lead conductor 422 when a high voltage is applied to the second spiral conductor 41 and the second lead conductors 421 and 422. In other words, the common mode noise filter 1 of this embodiment has the advantage of being able to further prevent a decrease in resistance to high voltages.

[0073] In the common mode noise filter 1 according to this embodiment, the first distance D1 (see FIG. 4), the second distance D2 (see FIGS. 4 and 5), and the third distance D3 (see FIG. 5) are the same. The first distance D1 is the distance in the up-down direction between the first spiral conductor 31 of the first conductor portion 3 and the second lead conductor 422 of the second conductor portion 4. The second distance D2 is the distance in the up-down direction between the first spiral conductor 31 of the first conductor portion 3 and the second spiral conductor 41 of the second conductor portion 4. The third distance D3 is the distance in the up-down direction between the second spiral conductor 41 of the second conductor portion 4 and the first lead conductor 322 of the first conductor portion 3.

[0074] This makes it possible to prevent an increase in electric field strength between the outermost periphery 315 of the first spiral conductor 31 and the first lead conductor 322, of the first lead conductors 321 and 322, which has a long conductive distance from the outermost periphery 315, when a high voltage is applied to the first spiral conductor 31 and the first lead conductor 321, 322. As a result, the common-mode noise filter 1 exhibits an effect of efficiently preventing fissures or cracks from occurring between the outermost periphery 315 of the first spiral conductor 31 and the first lead conductor 322, of the first lead conductors 321 and 322. Similarly, when a high voltage is applied to the second spiral conductor 41 and the second lead conductors 421, 422, the common-mode noise filter 1 exhibits an effect of efficiently preventing fissures or cracks from occurring between the outermost periphery 415 of the second spiral conductor 41 and the second lead conductor 422, of the second lead conductors 421 and 422, which has a long conductive distance from the outermost periphery 415. As described above, the common mode noise filter 1 has the advantage of being able to efficiently suppress a decrease in resistance to high voltages.

[0075] (4) Modifications The above-described embodiment is merely one of various embodiments of the present disclosure. The above-described embodiment can be modified in various ways depending on the design, etc., as long as the object of the present disclosure can be achieved. The following modifications may be realized in appropriate combination. The same components as those in the above-described embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

[0076] (4-1) First Modification First, a common mode noise filter 1A according to a first modification will be described with reference to Fig. 8. Fig. 8 is a cross-sectional view of a main part showing the configuration of the common mode noise filter 1A of the first modification.

[0077] In the common mode noise filter 1 of the above-described embodiment, the second spiral conductor 41 is provided between the first spiral conductor 31 and the first lead conductor 32 in the vertical direction. Also, in the common mode noise filter 1 of the above-described embodiment, the first spiral conductor 31 is provided between the second spiral conductor 41 and the second lead conductor 42 in the vertical direction. However, as shown in Fig. 8 , in the common mode noise filter 1A of the first modified example, the second lead conductor 42A is provided between the first spiral conductor 31A and the first lead conductor 32A in the vertical direction. Also, in the common mode noise filter 1A of the first modified example, the first lead conductor 32A is provided between the second spiral conductor 41A and the second lead conductor 42A in the vertical direction.

[0078] The detailed configuration of the common mode noise filter 1A of the first modified example will be described below.

[0079] The common mode noise filter 1A of the first modified example includes an element body 2, a first conductor portion 3A, a second conductor portion 4A, and vias B1, B2, B3, and B4.

[0080] The first conductor portion 3A has a first spiral conductor 31A, a first lead conductor 32A, and via pads 33, 34, 35, and 36. The first conductor portion 3A has two first lead conductors 321 and 322A as the first lead conductor 32A. Similarly, the second conductor portion 4A has a second spiral conductor 41A, a second lead conductor 42A, and via pads 43, 44, 45, and 46. The second conductor portion 4A has two second lead conductors 421 and 422A as the second lead conductor 42A. The first spiral conductor 31A and the second spiral conductor 41A of the first modified example have the same configuration as the first spiral conductor 31 and the second spiral conductor 41 of the above-described embodiment, and therefore detailed description thereof will be omitted as appropriate.

[0081] The first lead conductor 322A leads the second end 317 of the first spiral conductor 31A to the outer surface of the element body 2. As shown in FIG. 8 , the first lead conductor 322A is electrically connected to the first turn portion 311 (not shown in FIG. 8 ) via the via pad 34, the via B2, and the via pad 36. Similarly, the second lead conductor 422A leads the second end 417 of the second spiral conductor 41A to the outer surface of the element body 2. The second lead conductor 422A is electrically connected to the first turn portion 411 via the via pad 44, the via B4, and the via pad 46.

[0082] In the first modified example, the second spiral conductor 41A is provided on a first plane inside the element body 2. The first lead conductors 321 and 322A are provided on a second plane inside the element body 2. The second lead conductors 421 and 422A are provided on a third plane inside the element body 2. The first spiral conductor 31A is provided on a fourth plane inside the element body 2. The first to fourth planes are aligned in the vertical direction and parallel to each other.

[0083] In the first modified example, the second spiral conductor 41A is provided between the insulator layer 21 and the insulator layer 22. The first lead conductors 321 and 322A are provided between the insulator layer 22 and the insulator layer 23. The second lead conductors 421 and 422A are provided between the insulator layer 23 and the insulator layer 24. The first spiral conductor 31A is provided between the insulator layer 24 and the insulator layer 25.

[0084] That is, the second lead conductor 42A is provided between the first spiral conductor 31A and the first lead conductor 32A in the up-down direction. For example, the second lead conductor 42A in the first modified example extends from the via pad 44 toward the outer surface of the element body 2 so as to pass between the first spiral conductor 31A and the first lead conductor 32A in the up-down direction. With the above configuration, the distance between the first spiral conductor 31A and the first lead conductor 32A in the up-down direction is increased. Therefore, when a high voltage is applied to the first spiral conductor 31A and the first lead conductors 321, 322A, it is possible to suppress an increase in the electric field intensity between the outermost periphery 315 of the first spiral conductor 31A and the first lead conductor 322A, which is the first lead conductor 321, 322A that has a long conduction distance from the outermost periphery 315. As a result, the common-mode noise filter 1A of the first modification has the effect of suppressing the occurrence of fissures or cracks between the outermost periphery 315 of the first spiral conductor 31A and the first lead conductor 322A. In other words, the common-mode noise filter 1A of the first modification has the advantage of further suppressing the decrease in resistance to high voltages.

[0085] Similarly, in the first modified example, the first extraction conductor 32A is provided between the second spiral conductor 41A and the second extraction conductor 42A in the vertical direction. For example, the first extraction conductor 32A in the first modified example extends from the via pad 34 toward the outer surface of the element body 2 so as to pass between the second spiral conductor 41A and the second extraction conductor 42A in the vertical direction. With the above configuration, the distance between the second spiral conductor 41A and the second extraction conductor 42A in the vertical direction is increased. Therefore, when a high voltage is applied to the second spiral conductor 41A and the second extraction conductor 421, 422A, it is possible to suppress an increase in the electric field strength between the outermost periphery 415 of the second spiral conductor 41A and the second extraction conductor 422A, which is the second extraction conductor 421, 422A that has a long conduction distance from the outermost periphery 415. As a result, the common-mode noise filter 1A of the first modification has the effect of suppressing the occurrence of fissures or cracks between the outermost periphery 415 of the second spiral conductor 41A and the second lead conductor 422A. In other words, the common-mode noise filter 1A of the first modification has the advantage of further suppressing the decrease in resistance to high voltages.

[0086] Here, attention will be paid to the positional relationship between the first conductor portion 3A and the second conductor portion 4A.

[0087] In the first modified example, as shown in FIG. 8 , the fourth distance D4 and the fifth distance D5 are the same. The fourth distance D4 is the distance between the second spiral conductor 41A of the second conductor portion 4A and the first lead conductor 322A of the first conductor portion 3A in the vertical direction. The fifth distance D5 is the distance between the first lead conductor 322A of the first conductor portion 3A and the second lead conductor 422A of the second conductor portion 4A in the vertical direction. More specifically, the fourth distance D4 here is the distance between the bottom surface of the outermost periphery 415 of the second spiral conductor 41A of the second conductor portion 4A and the top surface of the first lead conductor 322A of the first conductor portion 3A in the vertical direction. Similarly, the fifth distance D5 here is the distance between the bottom surface of the first lead conductor 322A of the first conductor portion 3A and the top surface of the second lead conductor 422A of the second conductor portion 4A in the vertical direction.

[0088] Furthermore, the fifth distance D5 is the same as a sixth distance D6, which is the distance in the vertical direction between the second lead conductor 422A of the second conductor portion 4A and the first spiral conductor 31A of the first conductor portion 3A. More specifically, the sixth distance D6 is the distance in the vertical direction between the lower surface of the second lead conductor 422A of the second conductor portion 4A and the upper surface of the outermost periphery 315 of the first spiral conductor 31A of the first conductor portion 3A.

[0089] As described above, in the first modified example, the fourth distance D4, the fifth distance D5, and the sixth distance D6 are the same. With this configuration, when a high voltage is applied to the first spiral conductor 31A and the first lead conductors 321, 322A, the second spiral conductor 41A can efficiently suppress an increase in electric field strength between the outermost periphery 315 of the first spiral conductor 31A and the first lead conductor 322A, which is the first lead conductor 321, 322A that has a long conduction distance from the outermost periphery 315. As a result, the common-mode noise filter 1A of the first modified example exhibits the effect of efficiently suppressing the occurrence of fissures or cracks between the outermost periphery 315 of the first spiral conductor 31A and the first lead conductor 322A. Similarly, when a high voltage is applied to the second spiral conductor 41A and the second lead conductors 421, 422A, the common mode noise filter 1A of the first modified example has the effect of efficiently suppressing the occurrence of fissures or cracks between the outermost periphery 415 of the second spiral conductor 41A and the second lead conductor 422A, of the second lead conductors 421, 422A, which has the longest conduction distance from the outermost periphery 415. As described above, the common mode noise filter 1A of the first modified example has the advantage of efficiently suppressing a decrease in resistance to high voltages.

[0090] (4-2) Second Modification Next, a common mode noise filter 1B according to a second modification will be described with reference to Fig. 9. Fig. 9 is a cross-sectional view of a main part showing the configuration of the common mode noise filter 1B of the second modification.

[0091] In the common mode noise filter 1 of the above-described embodiment, the second spiral conductor 41 is provided between the first spiral conductor 31 and the first lead conductor 32 in the vertical direction. Also, in the common mode noise filter 1 of the above-described embodiment, the first spiral conductor 31 is provided between the second spiral conductor 41 and the second lead conductor 42 in the vertical direction. However, as shown in Fig. 9, in a common mode noise filter 1B of the second modified example, a second lead conductor 42B is provided between the first spiral conductor 31B and the first lead conductor 32B in the vertical direction. Also, in the common mode noise filter 1B of the second modified example, the first spiral conductor 31B is provided between the second spiral conductor 41B and the second lead conductor 42B in the vertical direction.

[0092] The detailed configuration of the common mode noise filter 1B of the second modified example will be described below.

[0093] The common mode noise filter 1B of the second modified example includes an element body 2, a first conductor portion 3B, a second conductor portion 4B, and vias B1, B2, B3, and B4.

[0094] The first conductor portion 3B has a first spiral conductor 31B, a first lead conductor 32B, and via pads 33, 34, 35, and 36. The first conductor portion 3B has two first lead conductors 321 and 322B as the first lead conductor 32B. Similarly, the second conductor portion 4B has a second spiral conductor 41B, a second lead conductor 42B, and via pads 43, 44, 45, and 46. The second conductor portion 4B has two second lead conductors 421 and 422B as the second lead conductor 42B. The first spiral conductor 31B and the second spiral conductor 41B of the second modified example have the same configuration as the first spiral conductor 31 and the second spiral conductor 41 of the above-described embodiment, and therefore detailed description thereof will be omitted as appropriate.

[0095] The first lead conductor 322B leads the second end 317 of the first spiral conductor 31B to the outer surface of the element body 2. The first lead conductor 322B is electrically connected to the first turn portion 311 (not shown in FIG. 9 ) via the via pad 36, the via B2, and the via pad 34. Similarly, the second lead conductor 422B leads the second end 417 of the second spiral conductor 41B to the outer surface of the element body 2. As shown in FIG. 9 , the second lead conductor 422B is electrically connected to the first turn portion 411 via the via pad 46, the via B4, and the via pad 44.

[0096] In the second modified example, the second spiral conductor 41B is provided on a first plane inside the element body 2. The first spiral conductor 31B is provided on a second plane inside the element body 2. The second lead conductors 421, 422B are provided on a third plane inside the element body 2. The first lead conductors 321, 322B are provided on a fourth plane inside the element body 2. The first to fourth planes are aligned in the vertical direction and parallel to each other.

[0097] In the second modification, the second spiral conductor 41B is provided between the insulator layer 21 and the insulator layer 22. The first spiral conductor 31B is provided between the insulator layer 22 and the insulator layer 23. The second lead conductors 421 and 422B are provided between the insulator layer 23 and the insulator layer 24. The first lead conductors 321 and 322B are provided between the insulator layer 24 and the insulator layer 25.

[0098] That is, the second lead conductor 42B is provided between the first spiral conductor 31B and the first lead conductor 32B in the vertical direction. For example, the second lead conductor 42B in the second modified example extends from the via pad 44 toward the outer surface of the element body 2 so as to pass between the first spiral conductor 31B and the first lead conductor 32B in the vertical direction. With the above configuration, the distance between the first spiral conductor 31B and the first lead conductor 32B in the vertical direction is increased. Therefore, when a high voltage is applied to the first spiral conductor 31B and the first lead conductors 321, 322B, it is possible to suppress an increase in the electric field strength between the outermost periphery 315 of the first spiral conductor 31B and the first lead conductor 322B, which is one of the first lead conductors 321, 322B and has a long conduction distance from the outermost periphery 315. As a result, the common-mode noise filter 1B of the second modification has the effect of suppressing the occurrence of fissures or cracks between the outermost periphery 315 of the first spiral conductor 31B and the first lead conductor 322B. In other words, the common-mode noise filter 1B of the second modification has the advantage of further suppressing the decrease in resistance to high voltages.

[0099] Similarly, in the second modified example, the first spiral conductor 31B is provided between the second spiral conductor 41B and the second lead conductors 421, 422B in the vertical direction. This configuration increases the vertical distance between the second spiral conductor 41B and the second lead conductors 421, 422B. Therefore, when a high voltage is applied to the second spiral conductor 41B and the second lead conductors 421, 422B, it is possible to prevent an increase in the electric field strength between the outermost periphery 415 of the second spiral conductor 41B and the second lead conductor 422B, which is the second lead conductor 421, 422B that has a long conduction distance from the outermost periphery 415. As a result, the common-mode noise filter 1B of the second modified example exhibits the advantage of being able to prevent cracks from occurring between the outermost periphery 415 of the second spiral conductor 41B and the second lead conductor 422B. That is, the common mode noise filter 1B of the second modified example has the advantage of being able to further suppress a decrease in resistance to high voltages.

[0100] Here, attention will be paid to the positional relationship between the first conductor portion 3B and the second conductor portion 4B.

[0101] In the second modified example, as shown in Fig. 9 , the seventh distance D7 and the eighth distance D8 are the same. The seventh distance D7 is the distance in the up-down direction between the second spiral conductor 41B of the second conductor portion 4B and the first spiral conductor 31B of the first conductor portion 3B. The eighth distance D8 is the distance in the up-down direction between the first spiral conductor 31B of the first conductor portion 3B and the second lead conductor 422B of the second conductor portion 4B. More specifically, the seventh distance D7 here is the distance in the up-down direction between the lower surface of the outermost periphery 415 of the second spiral conductor 41B of the second conductor portion 4B and the upper surface of the outermost periphery 315 of the first spiral conductor 31B of the first conductor portion 3B. Similarly, the eighth distance D8 here is, more specifically, the distance in the vertical direction between the lower surface of the outermost periphery 315 of the first spiral conductor 31B of the first conductor portion 3B and the upper surface of the second extraction conductor 422B of the second conductor portion 4B.

[0102] Furthermore, the eighth distance D8 is the same as a ninth distance D9, which is the distance in the up-down direction between the second lead conductor 422B of the second conductor portion 4B and the first lead conductor 322B of the first conductor portion 3B. More specifically, the ninth distance D9 is the distance in the up-down direction between the bottom surface of the second lead conductor 422B of the second conductor portion 4B and the top surface of the first lead conductor 322B of the first conductor portion 3B.

[0103]

[0047] As a result, in the second modified example, the seventh distance D7, the eighth distance D8, and the ninth distance D9 are the same. With this configuration, when a high voltage is applied to the first spiral conductor 31B and the first lead conductors 321, 322B, the second spiral conductor 41B can efficiently suppress an increase in electric field strength between the outermost periphery 315 of the first spiral conductor 31B and the first lead conductor 322B, which is the first lead conductor 321, 322B that has a long conduction distance from the outermost periphery 315. As a result, the common-mode noise filter 1B of the second modified example exhibits the effect of efficiently suppressing the occurrence of fissures or cracks between the outermost periphery 315 of the first spiral conductor 31B and the first lead conductor 322B. Similarly, the common-mode noise filter 1B of the second modification has the effect of efficiently preventing, when a high voltage is applied to the second spiral conductor 41B and the second lead conductors 421, 422B, cracks from occurring between the outermost periphery 415 of the second spiral conductor 41B and the second lead conductor 422B, of the second lead conductors 421, 422B, which has the longest conduction distance from the outermost periphery 415. As described above, the common-mode noise filter 1B of the second modification has the advantage of efficiently preventing a decrease in resistance to high voltages.

[0104] (4-3) Other Modifications Other modifications of the above-described embodiment are listed below. The following modifications may be implemented in appropriate combination.

[0105] In the above-described embodiment, each of the first spiral conductor 31 and the second spiral conductor 41 has a shape in which a conductor is wound multiple times around an oval. However, each of the first spiral conductor 31 and the second spiral conductor 41 may have a shape in which a conductor is wound multiple times around a circle or a rectangle.

[0106] In the above-described embodiment, the shape of the first lead conductor 321 is a rectangle with rounded corners when viewed from the top and bottom. However, the shape of the first lead conductor 321 is not limited to the shape of the above-described embodiment, as long as it allows the first end 316 of the first spiral conductor 31 to be led out to the outer surface of the element body 2. Similarly, the shape of the first lead conductor 322 is not limited to the shape of the above-described embodiment, as long as it allows the second end 317 of the first spiral conductor 31 to be led out to the outer surface of the element body 2.

[0107] In the above-described embodiment, the shape of the second lead conductor 421 is a rectangle with rounded corners when viewed from the top and bottom. However, the shape of the second lead conductor 421 is not limited to the shape of the above-described embodiment, as long as it allows the first end 416 of the second spiral conductor 41 to be led out to the outer surface of the element body 2. Similarly, the shape of the second lead conductor 422 is not limited to the shape of the above-described embodiment, as long as it allows the second end 417 of the second spiral conductor 41 to be led out to the outer surface of the element body 2.

[0108] In the above embodiment, the via B1 electrically connects the first spiral conductor 31 and the first lead conductor 321 through the via pads 33 and 35. However, the via B1 may electrically connect the first spiral conductor 31 and the first lead conductor 321 without going through the via pads 33 and 35. Similarly, the via B2 may electrically connect the first spiral conductor 31 and the first lead conductor 322 without going through the via pads 34 and 36. That is, the first conductor portion 3 does not have to have the via pads 33, 34, 35, and 36.

[0109] In the above embodiment, the via B3 electrically connects the second spiral conductor 41 and the second lead conductor 421 through the via pads 43 and 45. However, the via B3 may electrically connect the second spiral conductor 41 and the second lead conductor 421 without the via pads 43 and 45. Similarly, the via B4 may electrically connect the second spiral conductor 41 and the second lead conductor 422 without the via pads 44 and 46. That is, the second conductor portion 4 does not have to have the via pads 43, 44, 45, and 46.

[0110] In the above-described embodiment, the common mode noise filter 1 includes the magnetic member 5, but it does not necessarily have to include the magnetic member 5.

[0111] In the above-described embodiment, the common mode noise filter 1 has a rectangular parallelepiped shape with its axis extending in the vertical direction, but it may also have a cylindrical, square pyramidal, or truncated conical shape with its axis extending in the vertical direction.

[0112] 1 and 3 , in the above-described embodiment, the second lead conductor 42 is provided on the first plane, the first spiral conductor 31 is provided on the second plane, the second spiral conductor 41 is provided on the third plane, and the first lead conductor 32 is provided on the fourth plane. However, it is sufficient that the second spiral conductor 41 is provided between the first spiral conductor 31 and the first lead conductor 32, and that the first spiral conductor 31 is provided between the second spiral conductor 41 and the second lead conductor 42. For example, the first lead conductor 32 may be provided on the first plane, the second spiral conductor 41 on the second plane, the first spiral conductor 31 on the third plane, and the second lead conductor 42 on the fourth plane.

[0113] 8 , the second spiral conductor 41A is provided on the first plane, the first lead conductor 32A is provided on the second plane, the second lead conductor 42A is provided on the third plane, and the first spiral conductor 31A is provided on the fourth plane. However, it is sufficient that the second lead conductor 42A is provided between the first spiral conductor 31A and the first lead conductor 32A, and that the first lead conductor 32A is provided between the second spiral conductor 41A and the second lead conductor 42A. For example, the first spiral conductor 31A may be provided on the first plane, the second lead conductor 42A on the second plane, the first lead conductor 32A on the third plane, and the second spiral conductor 41A on the fourth plane.

[0114] 9 , the second spiral conductor 41B is provided on the first plane, the first spiral conductor 31B on the second plane, the second lead conductor 42B on the third plane, and the first lead conductor 32B on the fourth plane. However, it is sufficient that the second lead conductor 42B is provided between the first spiral conductor 31B and the first lead conductor 32B, and that the first spiral conductor 31B is provided between the second spiral conductor 41B and the second lead conductor 42B. For example, the first lead conductor 32B may be provided on the first plane, the second lead conductor 42B on the second plane, the first spiral conductor 31B on the third plane, and the second spiral conductor 41B on the fourth plane.

[0115] (Summary) A common mode noise filter (1, 1A, 1B) of a first aspect includes an element body (2), a first conductor portion (3, 3A, 3B), and a second conductor portion (4, 4A, 4B). The first conductor portion (3, 3A, 3B) and the second conductor portion (4, 4A, 4B) are provided inside the element body (2) and are aligned in the vertical direction. The first conductor portion (3, 3A, 3B) has a first spiral conductor (31, 31A, 31B) and a first lead conductor (32, 32A, 32B). The first spiral conductor (31, 31A, 31B) extends in a spiral shape. The first lead conductor (32, 32A, 32B) is provided on a different plane from the first spiral conductor (31, 31A, 31B) in the vertical direction, and both ends of the first spiral conductor (31, 31A, 31B) are each drawn to the outer surface of the element body (2). The second conductor portion (4, 4A, 4B) has a second spiral conductor (41, 41A, 41B) and a second lead conductor (42, 42A, 42B). The second spiral conductor (41, 41A, 41B) extends in a spiral shape. The second lead conductor (42, 42A, 42B) is provided on a different plane from the second spiral conductor (41, 41A, 41B) in the vertical direction, and both ends of the second spiral conductor (41, 41A, 41B) are each drawn to the outer surface of the element body (2). A second spiral conductor (41, 41A, 41B) or a second lead conductor (42, 42A, 42B) is provided between the first spiral conductor (31, 31A, 31B) and the first lead conductor (32, 32A, 32B) in the vertical direction.

[0116] This embodiment has the advantage of being able to suppress a decrease in resistance to high voltage.

[0117] In the common mode noise filter (1) of the second aspect, the second spiral conductor (41) is provided between the first spiral conductor (31) and the first lead conductor (32) in the vertical direction in the first aspect. The first spiral conductor (31) is provided between the second spiral conductor (41) and the second lead conductor (42) in the vertical direction.

[0118] This embodiment has the advantage that the decrease in resistance to high voltage can be further suppressed.

[0119] In the common mode noise filter (1) of the third aspect, in the second aspect, the first distance (D1), the second distance (D2), and the third distance (D3) are the same. The first distance (D1) is the distance between the second lead conductor (42) and the first spiral conductor (31) in the vertical direction. The second distance (D2) is the distance between the first spiral conductor (31) and the second spiral conductor (41) in the vertical direction. The third distance (D3) is the distance between the second spiral conductor (41) and the first lead conductor (32) in the vertical direction.

[0120] This embodiment has the advantage that the decrease in resistance to high voltage can be efficiently suppressed.

[0121] In the common mode noise filter (1A) of the fourth aspect, in the first aspect, a second lead conductor (42A) is provided between the first spiral conductor (31A) and the first lead conductor (32A) in the vertical direction. The first lead conductor (32A) is provided between the second spiral conductor (41A) and the second lead conductor (42A) in the vertical direction.

[0122] This embodiment has the advantage that the decrease in resistance to high voltage can be further suppressed.

[0123] In the common mode noise filter (1A) of the fifth aspect, in the fourth aspect, the fourth distance (D4), the fifth distance (D5), and the sixth distance (D6) are the same. The fourth distance (D4) is the distance between the second spiral conductor (41A) and the first lead conductor (32A) in the vertical direction. The fifth distance (D5) is the distance between the first lead conductor (32A) and the second lead conductor (42A) in the vertical direction. The sixth distance (D6) is the distance between the second lead conductor (42A) and the first spiral conductor (31A) in the vertical direction.

[0124] This embodiment has the advantage that the decrease in resistance to high voltage can be efficiently suppressed.

[0125] In the common mode noise filter (1B) of the sixth aspect, in the first aspect, a second lead conductor (42B) is provided between the first spiral conductor (31B) and the first lead conductor (32B) in the vertical direction. The first spiral conductor (31B) is provided between the second spiral conductor (41B) and the second lead conductor (42B) in the vertical direction.

[0126] This embodiment has the advantage that the decrease in resistance to high voltage can be further suppressed.

[0127] In the common mode noise filter (1B) of the seventh aspect, in the sixth aspect, the seventh distance (D7), the eighth distance (D8), and the ninth distance (D9) are the same. The seventh distance (D7) is the distance between the second spiral conductor (41B) and the first spiral conductor (31B) in the vertical direction. The eighth distance (D8) is the distance between the first spiral conductor (31B) and the second lead conductor (42B) in the vertical direction. The ninth distance (D9) is the distance between the second lead conductor (42B) and the first lead conductor (32B) in the vertical direction.

[0128] This embodiment has the advantage that the decrease in resistance to high voltage can be efficiently suppressed.

[0129] 1, 1A, 1B Common mode noise filter 2 Element body 3, 3A, 3B First conductor portion 4, 4A, 4B Second conductor portion 31, 31A, 31B First spiral conductor 32, 32A, 32B First lead conductor 41, 41A, 41B Second spiral conductor 42, 42A, 42B Second lead conductor D1 First distance D2 Second distance D3 Third distance D4 Fourth distance D5 Fifth distance D6 Sixth distance D7 Seventh distance D8 Eighth distance D9 Ninth distance

Claims

1. A common mode noise filter comprising: an element body; and a first conductor portion and a second conductor portion arranged inside the element body and aligned in a vertical direction, wherein the first conductor portion has a first spiral conductor extending in a spiral shape; and a first lead-out conductor arranged on a different plane from the first spiral conductor in the vertical direction, and leading out each of both ends of the first spiral conductor to the outer surface of the element body, wherein the second conductor portion has a second spiral conductor extending in a spiral shape; and a second lead-out conductor arranged on a different plane from the second spiral conductor in the vertical direction, and leading out each of both ends of the second spiral conductor to the outer surface of the element body, wherein the second spiral conductor or the second lead-out conductor is arranged between the first spiral conductor and the first lead-out conductor in the vertical direction.

2. A common mode noise filter as described in claim 1, wherein the second spiral conductor is provided between the first spiral conductor and the first lead-out conductor in the vertical direction, and the first spiral conductor is provided between the second spiral conductor and the second lead-out conductor in the vertical direction.

3. A common mode noise filter as described in claim 2, wherein a first distance, which is the distance between the second lead-out conductor and the first spiral conductor in the vertical direction, a second distance, which is the distance between the first spiral conductor and the second spiral conductor in the vertical direction, and a third distance, which is the distance between the second spiral conductor and the first lead-out conductor in the vertical direction, are the same.

4. A common mode noise filter as described in claim 1, wherein the second lead-out conductor is provided between the first spiral conductor and the first lead-out conductor in the vertical direction, and the first lead-out conductor is provided between the second spiral conductor and the second lead-out conductor in the vertical direction.

5. A common mode noise filter as described in claim 4, wherein a fourth distance, which is the distance between the second spiral conductor and the first lead-out conductor in the vertical direction, a fifth distance, which is the distance between the first lead-out conductor and the second lead-out conductor in the vertical direction, and a sixth distance, which is the distance between the second lead-out conductor and the first spiral conductor in the vertical direction, are the same.

6. A common mode noise filter as claimed in claim 1, wherein the second lead-out conductor is provided between the first spiral conductor and the first lead-out conductor in the vertical direction, and the first spiral conductor is provided between the second spiral conductor and the second lead-out conductor in the vertical direction.

7. A common mode noise filter as described in claim 6, wherein a seventh distance, which is the distance between the second spiral conductor and the first spiral conductor in the vertical direction, an eighth distance, which is the distance between the first spiral conductor and the second lead-out conductor in the vertical direction, and a ninth distance, which is the distance between the second lead-out conductor and the first lead-out conductor in the vertical direction, are the same.

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