JP2021141487A - Noise filter - Google Patents

Abstract

To provide a noise filter that can suppress the circuit area and volume.SOLUTION: A noise filter has a first surface and a second surface. The noise filter includes a first conductive wire that is placed on the substrate and in which one end is connected to a first end. The noise filter includes a second conductive wire that is arranged parallel to the first conductive wire on the substrate and in which one end is connected to the second end. The noise filter includes a connecting conductive wire that connects the other end of the first conductive wire and the other end of the second conductive wire in a direction in which a current flows in the same direction to the first conductive wire and the second conductive wire. The noise filter includes a capacitor that connects the connecting conductive wire and the reference potential portion. The noise filter includes a magnetic material that surrounds peripheries of the first conductive wire and the second conductive wire without surrounding a periphery of the connecting conductive wire. The magnetic material penetrates the substrate and is arranged on the first surface side and the second surface side of the substrate.SELECTED DRAWING: Figure 3

Description

The techniques disclosed herein relate to noise filters.

A noise filter is being developed in order to suppress electromagnetic noise superimposed on the conductive wire. Many of these types of noise filters are equipped with a capacitor to bypass electromagnetic noise from the conductive wire to GND. However, the capacitor has a parasitic inductance called Equivalent Series Inductance (ESL), and the wiring to which the capacitor is connected also has a parasitic inductance. Therefore, it is known that such a noise filter cannot exhibit good filter performance against electromagnetic noise in a high frequency band due to the influence of these parasitic inductances.

In Patent Document 1, two winding coils (reactors) are arranged to face each other in the same plane of the printed circuit board, or two winding coils are arranged to face each other in the vertical direction of the printed circuit board. A technique for coupling magnetic fluxes is disclosed. As a result, the filter performance is improved by canceling the equivalent series inductance of the capacitor with the negative mutual inductance.

Japanese Unexamined Patent Publication No. 2016-31965

In the technique of Patent Document 1, since two winding coils are used to generate mutual inductance, there is a problem that the area and volume of the circuit become large. In power electronics that handle large currents, the wiring width and wiring cross-sectional area are large, which is a particular problem.

One embodiment of the noise filter disclosed herein comprises a substrate with first and second surfaces. The noise filter is arranged on the substrate and includes a first conductive wire having one end connected to the first end portion. The noise filter includes a second conductive wire that is arranged parallel to the first conductive wire on the substrate and one end of which is connected to the second end portion. The noise filter includes a connecting conductive wire that connects the other end of the first conductive wire and the other end of the second conductive wire in a direction in which a current flows in the same direction as the first conductive wire and the second conductive wire. The noise filter includes a capacitor that connects the connecting conductive wire and the reference potential portion. The noise filter includes a magnetic material that surrounds the first conductive wire and the second conductive wire without surrounding the connection conductive wire. The magnetic material penetrates the substrate and is arranged on the first surface side and the second surface side of the substrate.

The noise filter of the above embodiment has a structure in which a magnetic material surrounds the first conductive wire and the second conductive wire. Further, the connecting conductive wire connecting the other end of the first conductive wire and the other end of the second conductive wire has a structure in which the periphery is not surrounded by a magnetic material, and the connecting conductive wire and the reference potential portion are capacitors. It has a structure connected by. As a result, the equivalent series inductance of the capacitor and the parasitic inductance of the connected conductive wire can be reduced by the magnetic coupling of the first conductive wire and the second conductive wire. Since it is not necessary to provide a structure (eg, two winding coils or the like) for enhancing the magnetic coupling, it is possible to suppress the circuit area and volume of the noise filter.

The magnetic material may be configured so that the first conductive wire and the second conductive wire are magnetically coupled, and the equivalent series inductance of the capacitor and the parasitic inductance of the connected conductive wire are reduced by the mutual inductance generated between them. Details of the effect will be described in Examples.

The first conductive wire may be arranged on the first surface of the substrate. The second conductive wire may be arranged on the second surface of the substrate. When the substrate is viewed from above vertically, at least a part of the first conductive wire and the second conductive wire may overlap. The magnetic material may be arranged so as to surround at least a part of the region where the first conductive wire and the second conductive wire overlap. The connecting conductive wire may include a first connecting conductive wire arranged on the first surface of the substrate and connected to the other end of the first conductive wire. The connecting conductive wire may include a second connecting conductive wire arranged on the second surface of the substrate and connected to the other end of the second conductive wire. The second connecting conductive wire may overlap with the first connecting conductive wire when the substrate is viewed from above vertically. The connecting conductive wire may be arranged in the overlapping region and may include via wiring that penetrates the substrate and connects the first connecting conductive wire and the second connecting conductive wire. Details of the effect will be described in Examples.

The first conductive wire and the second conductive wire may be arranged on the first surface of the substrate. The connecting conductive wire may include a first connecting conductive wire arranged on the first surface of the substrate and connected to the other end of the first conductive wire. The connecting conductive wire may include a second connecting conductive wire arranged on the second surface of the substrate. The second connecting conductive wire has a first overlapping region that overlaps with the first connecting conductive wire and a second overlapping region that overlaps with the other end of the second conductive wire when the substrate is viewed from above vertically. May be provided. The noise filter may be arranged in the first overlapping region and may include a first via wire that penetrates the substrate and connects the second connecting conductive wire and the first connecting conductive wire. The noise filter may be arranged in the second overlapping region and may include a second via wire that penetrates the substrate and connects the second connecting conductive wire to the other end of the second conductive wire. .. Details of the effect will be described in Examples.

The first conductive wire and the second conductive wire may be arranged on the first surface of the substrate. The connecting conductive wire may include a first connecting conductive wire arranged on the first surface of the substrate and connected to the other end of the first conductive wire. The connecting conductive wire may include a second connecting conductive wire that is arranged on the first surface of the substrate and connects the first connecting conductive wire and the other end of the second conductive wire. The second connecting conductive wire may include an intersecting region that intersects the first conductive wire when the substrate is viewed from above vertically. Since the second connecting conductive wire is located above the first conductive wire in the intersecting region, the second connecting conductive wire and the first conductive wire may be insulated from each other. Details of the effect will be described in Examples.

The substrate may include two through holes arranged side by side in a second direction orthogonal to the first direction in which the first conductive wire and the second conductive wire extend. The two through holes may be arranged at positions facing each other with the first conductive wire and the second conductive wire interposed therebetween. The magnetic material may include a first magnetic material portion and a second magnetic material portion that form a cyclic structure when combined. The first magnetic material portion and the second magnetic material portion may be combined via two through holes. Details of the effect will be described in Examples.

A gap may be formed at the joint portion between the first magnetic material portion and the second magnetic material portion. Details of the effect will be described in Examples.

The first magnetic material portion includes two columnar portions that can be fitted into the two through holes and a connecting portion that is configured to connect between the first ends of the two columnar portions. It may have a substantially U-shape. The second magnetic body portion may have a substantially I-shape that can be arranged so as to connect between the second ends of the two columnar portions. Details of the effect will be described in Examples.

The capacitors may include a first capacitor and a second capacitor connected in series with each other. Details of the effect will be described in Examples.

It is a figure explaining the noise transmission characteristic of the T-type noise filter of an LCL configuration. It is a figure explaining the noise transmission characteristic of the T-type noise filter of an LCL configuration. It is a figure which shows typically the perspective view of the noise filter 1a which concerns on Example 1. FIG. It is an exploded perspective view of the noise filter 1a which concerns on Example 1. FIG. It is sectional drawing in the VV line of FIG. It is a figure which shows typically the perspective view of the noise filter 1b which concerns on Example 2. FIG. It is a figure which shows typically the perspective view of the noise filter 1c which concerns on Example 3. FIG.

(Principle of noise reduction effect)
Before explaining the noise filter disclosed in the present specification, the noise transmission characteristic of the T-type noise filter 1 having an LCL configuration will be described with reference to FIG. The noise filter 1 includes a pair of inductors L1 and L2 connected in series with the power conductive wire, and a capacitor C connected between the power conductive wire and the reference conductive wire. Inductance of the inductor L1 is _{L 1,} the inductance of the inductor L2 is _{L 2.} The inductors L1 and L2 may be parasitic inductors of power conductive wires. One end of the capacitor C is connected to a branch portion between the pair of inductors L1 and L2, and the other end is connected to a reference conductive wire. Inductance L ₃ of the inductor L3 is the ESL of the capacitor C, which is the sum of the parasitic inductance of the wiring capacitor C is connected. Z ₁ is the internal impedance of the noise source, and Z ₂ is the impedance of the load circuit. In this noise filter 1, the inductor L1 and the inductor L2 are magnetically coupled. It is assumed that the currents I ₁ and I ₂ flowing through the inductors L1 and L2 flow in the directions shown in the drawing, and that a positive mutual inductance M is generated between the inductors L1 and L2. _Assuming that the noise voltage is V _{noise, the noise voltage VL} applied to the load circuit is expressed by the following equation.

Ｚ_Ｌ１：インダクタＬ１のインピーダンス（jω(L₁＋M)）
Ｚ_Ｌ２：インダクタＬ２のインピーダンス（jω(L₂＋M)）
Ｚ_Ｌ３：コンデンサＣの等価直列インダクタとコンデンサＣが接続される配線の寄生インダクタの和からなるインピーダンス（jω(L₃−M)）
Ｚ_Ｃ：コンデンサＣのインピーダンス（1/jωC）
ω：角周波数（２πｆ）

Z _L1 : Impedance of inductor L1 (jω (L ₁ + M))
Z _L2 : Impedance of inductor L2 (jω (L ₂ + M))
Z _L3 : Impedance consisting of the sum of the equivalent series inductor of the capacitor C and the parasitic inductor of the wiring to which the capacitor C is connected (jω (L ₃ −M))
Z _C : Impedance of capacitor C (1 / jωC)
ω: Angular frequency (2πf)

As shown in the above equation 1, in order to reduce the _{noise voltage VL} applied to the load circuit, it is important to reduce the _{numerator "Z L3} + Z _C". Since the amplitude of the noise voltage _VL is expressed by an absolute value, if the absolute value of the above equation 1 is taken and the molecule is V _num , it can be expressed by the following equation.

According to the above equation 2, it can be seen that the filter performance is maximized when the mutual inductance M is set so that _{{ω (L 3-M) -1 / ωC} becomes 0.} However, such conditions are only realized at certain arbitrary frequencies. Therefore, a noise filter circuit for reducing noise in a wide range of frequencies is not set under such conditions.

Here, the mutual inductance M generated between the inductor L1 and the inductor L2 can be expressed by the following mathematical formula using the coupling coefficient k.

The coupling coefficient k is a value indicating the degree of magnetic coupling, and in the structure disclosed in the present specification, it takes a value of 0 ≦ k ≦ 1. As shown in the above formula 2 and the above formula 3, _{if the values of k, L 1} , and L _{2 are adjusted so that the inductance L 3} and the mutual inductance M match, the molecule of the above formula 1 can be the capacitor C. Only the product of the impedance and the impedance of the load circuit remains. Since the angular frequency ω becomes larger with increasing frequency, if matching the inductance L ₃ and the mutual inductance M, the filter performance is improved with respect to electromagnetic noise of a high frequency band.

That is, as shown in FIG. 2, by an inductor L1 and inductor L2 are magnetically coupled, if Sasere reduce the inductance L ₃ by the mutual inductance M that occurs between the inductor L1 and the inductor L2, to electromagnetic noise of a high frequency band The filter performance can be improved. The techniques disclosed herein utilize this phenomenon to improve filter performance against electromagnetic noise in the high frequency band.

(Structure of noise filter 1a)
FIG. 3 shows a perspective view of the noise filter 1a according to the first embodiment. FIG. 4 shows an exploded perspective view of the noise filter 1a. FIG. 5 shows a cross-sectional view taken along the line VV of FIG. The noise filter 1a is formed by using a double-sided substrate 10 having a back surface S1 and a front surface S2. In FIG. 3, the conductive layer on the back surface S1 is shown in white, and the conductive layer on the front surface S2 is shown in light gray. The conductive layer of each layer is a metal pattern formed on an insulating substrate (printed circuit board). Further, of the magnetic material portion 71, the range visible in the perspective view is shown in dark gray.

The noise filter 1a includes an output side conductive wire 11, an input side conductive wire 12, a ground plate 15, capacitors 31 and 32, a connection pad 63, via wiring 41, connection conductive wires 61 and 62, and a magnetic core 70. ..

An output-side conductive wire 11 and a connecting conductive wire 61 are formed on the back surface S1. The end portion E11 on the + x direction side of the output side conductive wire 11 is an output end portion and is connected to an arbitrary load. An input-side conductive wire 12 and a connecting conductive wire 62 are formed on the surface S2. The end E21 on the −x direction side of the input-side conductive wire 12 is an input end and is connected to a power converter (not shown) such as a converter or an inverter which is a noise source. The output-side conductive wire 11 and the input-side conductive wire 12 have a straight flat plate structure and face each other via an insulating substrate. As a result, both electric wires are arranged in parallel while being insulated from each other, and are arranged in close proximity to each other in a straight line. When the double-sided substrate 10 is viewed from vertically above (+ z direction), the output-side conductive wire 11 and the input-side conductive wire 12 have a region A1 that overlaps with each other (see FIG. 4).

The connecting conductive wire 61 arranged on the back surface S1 is integrally formed with the output-side conductive wire 11, and protrudes from the end portion E12 in the −y direction. The connecting conductive wire 62 arranged on the surface S2 is integrally formed with the input-side conductive wire 12, and projects from the end E22 in the −y direction and extends in the −x direction. The connecting conductive wire 62 includes an overlapping region DA1 that overlaps with the connecting conductive wire 61 when the double-sided substrate 10 is viewed from vertically above (+ z direction) (see FIG. 3). The via wiring 41 is arranged in the overlapping region DA1 and penetrates the double-sided substrate 10 to connect the connecting conductive wires 61 and 62. As a result, the end E22 of the input-side conductive wire 12 and the end E12 of the output-side conductive wire 11 are electrically connected. Therefore, the input-side conductive wire 12 and the output-side conductive wire 11 are arranged in a direction in which a current flows in the same direction when a current flows between the end portion E21 and the end portion E11.

As shown in FIG. 4, the double-sided substrate 10 includes two through holes H1 and H2 arranged side by side in the y direction. The through holes H1 and H2 are arranged at positions facing each other with the output-side conductive wire 11 and the input-side conductive wire 12 interposed therebetween. The magnetic core 70 includes a substantially U-shaped magnetic material portion 71 and a substantially I-shaped magnetic material portion 72. The magnetic bodies 71 and 72 form an annular structure when combined. The magnetic body portion 71 includes columnar portions P1 and P2 and a connecting portion J1. The connecting portion J1 is a portion that connects the end portion of the columnar portion P1 on the + z direction side and the end portion of the columnar portion P2 on the + z direction side. The columnar portions P1 and P2 have a shape that can be fitted into the through holes H1 and H2. The magnetic material portion 72 can be combined so as to connect the end portion of the columnar portion P1 on the −z direction side and the end portion of the columnar portion P2 on the −z direction side.

By combining the magnetic material portions 71 and 72 through the through holes H1 and H2, the magnetic material core 70 that penetrates the double-sided substrate 10 and is arranged on the back surface S1 side and the front surface S2 side of the double-sided substrate 10 is formed. be able to. As a result, the magnetic core 70 can be arranged so as to surround at least a part of the region A1 where the output side conductive wire 11 and the input side conductive wire 12 overlap. Further, the magnetic core 70 does not surround the connecting conductive wires 61 and 62. An insulating layer for preventing contact may be arranged between the outer circumferences of the output side conductive wire 11 and the input side conductive wire 12 and the inner circumference of the magnetic core 70.

As shown in FIG. 5, a gap G1 is formed at the joint portion between the magnetic material portions 71 and 72. By adjusting the gap G1, the mutual inductance between the output-side conductive wire 11 and the input-side conductive wire 12 can be adjusted. The gap G1 may be adjusted by an insulator spacer (not shown). Further, by using a combination of the U-shaped magnetic material portion 71 and the I-shaped magnetic material portion 72, one of the joint portions of both can be made flat. Therefore, it is possible to reduce the processing difficulty of the magnetic core 70 and facilitate the adjustment of the gap G1.

The connection conductive wire 62 and the ground plate 15 are connected via a capacitor 31, a connection pad 63, and a capacitor 32. That is, the connecting conductive wire 62 and the ground plate 15 are connected by capacitors 31 and 32 connected in series with each other. By adopting a structure in which a plurality of capacitors are connected in series, it is possible to provide redundancy so that the connecting conductive wire 62 does not short-circuit with the ground plate 15 even if any of the capacitors fails in a short circuit. In the examples of FIGS. 3 to 5, the capacitors 31 and 32 are three parallel chip capacitors (multilayer ceramic capacitors).

As described above, the noise filter 1a includes the parasitic inductance of the input side conductive wire 12, the capacitors 31 and 32 inserted between the connection path between the connection conductive wire 62 and the ground plate 15, and the output side conductivity. It is a T-type noise filter having an LCL configuration composed of the parasitic inductance of the wire 11.

(effect)
The noise filter 1a of this embodiment has a structure in which the magnetic core 70 collectively surrounds the output side conductive wire 11 and the input side conductive wire 12. As a result, a higher magnetic field coupling can be obtained than in a structure in which the output side conductive wire 11 and the input side conductive wire 12 simply run in parallel. Further, the connecting conductive wires 61 and 62 connecting the end E12 of the output side conductive wire 11 and the end E22 of the input side conductive wire 12 have a structure in which the magnetic core 70 does not surround the periphery, and the connecting conductive wire 61 and 62 are not surrounded by the magnetic core 70. The wire 62 and the ground plate 15 are connected by capacitors 31 and 32. As a result, the sum of the equivalent series inductance of the capacitors 31 and 32 and the parasitic inductance of the connecting conductive wires 61 and 62 can be reduced by the mutual inductance generated between the output side conductive wire 11 and the input side conductive wire 12. As shown by the above formula 2, it is possible to exhibit high filter performance against electromagnetic noise in the high frequency band. As a method of increasing the mutual inductance, the cross-sectional area of the annular magnetic path formed by the magnetic core 70 (eg, the cross-sectional area of the xy planes of the columnar portions P1 and P2, and the disconnection of the zx plane of the magnetic body portion 72). There is a method of increasing the area) and a method of decreasing the gap G1.

By providing a structure in which the output side conductive wire 11 and the input side conductive wire 12 are surrounded by the magnetic material core 70, another structure for enhancing the magnetic coupling between the two electric wires (eg, two winding coils, etc.). There is no need to prepare. Therefore, it is possible to suppress the circuit area and volume of the noise filter 1a. Further, the portion where the output side conductive wire 11 and the input side conductive wire 12 penetrate the magnetic core 70 can be formed into a linear shape. Since the area ratio of the conductive wire to the noise filter 1a can be reduced as compared with the case where the conductive wire is processed into a coil shape, the circuit area can be suppressed.

The mutual inductance generated between the input-side conductive wire 12 and the output-side conductive wire 11 does not necessarily have to match the sum of the equivalent series inductance of the capacitors 31 and 32 and the parasitic inductance of the connecting conductive wires 61 and 62. If the mutual inductance is "M" and the sum of the equivalent series inductance of the capacitors 31 and 32 and the parasitic inductance of the connecting conductive wires 61 and 62 is "L ₃ ", then M is such that _{| L 3-} M | <L _3. By adjusting, the filter performance of the noise filter 1a can be improved.

FIG. 6 shows a perspective view of the noise filter 1b according to the second embodiment. The common parts of the noise filter 1b of the second embodiment and the noise filter 1a of the first embodiment are designated by the same reference numerals, and the description thereof will be omitted. Further, the parts peculiar to the second embodiment are distinguished by adding "b" to the end of the reference numerals.

The output-side conductive wire 11b and the input-side conductive wire 12b are arranged parallel to each other on the surface S2 of the double-sided substrate 10. The connecting conductive wire 61b is formed integrally with the output-side conductive wire 11b, projects from the end E12 in the −y direction, and extends in the + x direction. The connecting conductive wire 64b is arranged on the back surface S1. The connecting conductive wire 64b overlaps the overlapping region DA11 that overlaps with the connecting conductive wire 61b and the end E22 of the input side conductive wire 12b when the double-sided substrate 10 is viewed from vertically above (+ z direction). It includes a region DA12. The via wiring 41b is arranged in the overlapping region DA11 and penetrates the double-sided substrate 10 to connect the connecting conductive wires 61b and 64b. The via wiring 42b is arranged in the overlapping region DA12, and penetrates the double-sided substrate 10 to connect the connecting conductive wire 64b and the input side conductive wire 12b. As a result, the end E22 of the input-side conductive wire 12b and the end E12 of the output-side conductive wire 11b are electrically connected.

(effect)
In the noise filter 1b of the second embodiment, the connecting conductive wire 64b that intersects the output side conductive wire 11b when the double-sided substrate 10 is viewed from vertically above is opposite to the surface S2 on which the output side conductive wire 11b is arranged. By arranging it on the back surface S1 of the above, a grade separation structure is formed. As a result, even when the output side conductive wire 11b and the input side conductive wire 12b are arranged on the same surface of the substrate, a current can be passed through both conductive wires in the same direction. Also in the noise filter 1b of the second embodiment, it is possible to enhance the filter effect and suppress the circuit area and the volume in the same manner as the noise filter 1a of the first embodiment.

FIG. 7 shows a perspective view of the noise filter 1c according to the third embodiment. The common parts of the noise filter 1c of the third embodiment and the noise filter 1b of the second embodiment are designated by the same reference numerals, and the description thereof will be omitted. Further, the parts peculiar to Example 3 are distinguished by adding "c" to the end of the reference numerals.

The output-side conductive wire 11b and the input-side conductive wire 12b are arranged parallel to each other on the surface S2 of the single-sided substrate 10c. The single-sided substrate 10c is a substrate in which a metal pattern is formed only on the surface S2. The connecting conductive wire 64c is arranged above the surface S2 (in the + z direction). The connecting conductive wire 64c overlaps with the output side conductive wire 11b, the end portion E22 of the input side conductive wire 12b, and the end portion E13 of the connecting conductive wire 61b when the single-sided substrate 10c is viewed from vertically above (+ z direction). There is. Further, the connecting conductive wire 64c is bent so that the intersecting region A2 intersecting the output side conductive wire 11b projects upward (+ z direction) from the surface S2. As a result, the connecting conductive wire 64c and the output-side conductive wire 11b are arranged apart from each other, so that they are insulated from each other. The end portion of the connecting conductive wire 64c in the −y direction is fixed to the surface of the end portion E13 of the connecting conductive wire 61b. The end of the connecting conductive wire 64c in the + y direction is fixed to the surface of the end E22 of the input-side conductive wire 12b. The connecting conductive wire 64c may be fixed by welding or soldering.

Although specific examples of the present invention have been described in detail above, these are merely examples and do not limit the scope of claims. The techniques described in the claims include various modifications and modifications of the specific examples illustrated above. In addition, the technical elements described in the present specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the techniques illustrated in the present specification or drawings can achieve a plurality of purposes at the same time, and achieving one of the purposes itself has technical usefulness.

(Modification example)
The number and placement of via wiring and capacitors are examples. Further, the resistance of the via wiring may be reduced by arranging the plurality of via wiring so as to be connected in parallel. Further, although the noise filter of the present specification uses three parallel capacitors, it is also possible to use one capacitor.

The shape of the magnetic core 70 may be any shape as long as it collectively encloses the input-side conductive wire and the output-side conductive wire.

The technique disclosed in the present specification is not limited to the example of the T-type noise filter having an LCL configuration, and can be applied to other types of noise filters.

The output-side conductive wire 11 or the input-side conductive wire 12 is an example of the first conductive wire. The input-side conductive wire 12 or the output-side conductive wire 11 is an example of the second conductive wire.

1, 1a, 1b, 1c: Noise filter 10 Double-sided board 11: Output side conductive wire 12: Input side conductive wire 15: Ground plate 31, 32: Capacitor 41: Via wiring 70: Magnetic material core 71, 72: Magnetic material part

Claims (9)

A substrate having a first surface and a second surface,
A first conductive wire arranged on the substrate and one end connected to the first end portion,
A second conductive wire arranged parallel to the first conductive wire on the substrate and having one end connected to the second end portion.
A connecting conductive wire connecting the other end of the first conductive wire and the other end of the second conductive wire in a direction in which a current flows in the same direction as the first conductive wire and the second conductive wire.
A capacitor that connects the connecting conductive wire and the reference potential portion,
A magnetic material that surrounds the first conductive wire and the second conductive wire without surrounding the circumference of the connecting conductive wire, and penetrates the substrate to the first surface side of the substrate and the said. The magnetic material arranged on the second surface side and
Noise filter with. The magnetic material is configured to magnetically couple the first conductive wire and the second conductive wire, and reduce the equivalent series inductance of the capacitor and the parasitic inductance of the connected conductive wire by the mutual inductance generated between them. The noise filter according to claim 1. The first conductive wire is arranged on the first surface of the substrate.
The second conductive wire is arranged on the second surface of the substrate.
When the substrate is viewed from above vertically, at least a part of the first conductive wire and the second conductive wire overlap with each other.
The magnetic material is arranged so as to surround at least a part of the region where the first conductive wire and the second conductive wire overlap.
The connecting conductive wire is
A first connecting conductive wire arranged on the first surface of the substrate and connected to the other end of the first conductive wire,
A second connecting conductive wire arranged on the second surface of the substrate and connected to the other end of the second conductive wire, and the first connecting conductive wire when the substrate is viewed from vertically above. The second connecting conductive wire having an overlapping region overlapping with the above-mentioned second connecting conductive wire,
Via wiring, which is arranged in the overlapping region and penetrates the substrate to connect the first connecting conductive wire and the second connecting conductive wire,
The noise filter according to claim 1 or 2. The first conductive wire and the second conductive wire are arranged on the first surface of the substrate.
The connecting conductive wire is
A first connecting conductive wire arranged on the first surface of the substrate and connected to the other end of the first conductive wire,
A first overlapping region which is a second connecting conductive wire arranged on the second surface of the substrate and which overlaps with the first connecting conductive wire when the substrate is viewed from vertically above. A second connecting conductive wire having a second overlapping region that overlaps with the other end of the second conductive wire.
A first via wiring arranged in the first overlapping region and penetrating the substrate to connect the second connecting conductive wire and the first connecting conductive wire.
A second via wiring arranged in the second overlapping region, penetrating the substrate and connecting the second connecting conductive wire and the other end of the second conductive wire,
The noise filter according to claim 1 or 2. The first conductive wire and the second conductive wire are arranged on the first surface of the substrate.
The connecting conductive wire is
A first connecting conductive wire arranged on the first surface of the substrate and connected to the other end of the first conductive wire,
A second connecting conductive wire arranged on the first surface of the substrate and connecting the first connecting conductive wire and the other end of the second conductive wire.
The second connecting conductive wire having an intersecting region intersecting with the first conductive wire when the substrate is viewed from above vertically.
With
Claim 1 in which the second connecting conductive wire and the first conductive wire are insulated from each other by being located above the first conductive wire in the intersecting region. Or the noise filter according to 2. The substrate is two through holes arranged side by side in a second direction orthogonal to the first direction in which the first conductive wire and the second conductive wire extend, and the first conductive wire and the second conductive wire. It is provided with the above-mentioned two through holes arranged at positions facing each other across a wire.
The magnetic material includes a first magnetic material portion and a second magnetic material portion which form a cyclic structure when combined.
The noise filter according to any one of claims 1 to 5, wherein the first magnetic material portion and the second magnetic material portion are combined via the two through holes. The noise filter according to claim 6, wherein a gap is formed at a joint portion between the first magnetic material portion and the second magnetic material portion. The first magnetic material portion is
Two columnar parts that can be fitted into the two through holes,
A connecting portion configured to connect between the first ends of the two columnar portions, and a connecting portion.
It has a substantially U-shape with
The noise filter according to claim 6 or 7, wherein the second magnetic material portion has a substantially I-shape that can be arranged so as to connect between the second end portions of the two columnar portions. The noise filter according to any one of claims 1 to 8, wherein the capacitor includes a first capacitor and a second capacitor connected in series with each other.

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