JP2006351954A - Stacked common mode filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stacked common mode filter capable of improving a high-frequency characteristic by reducing a floating capacity. <P>SOLUTION: A first conductor 22 exhibits a spiral shape, and is connected to a first terminal electrode. A second conductor 23 extends from a position corresponding to the internal end of the first conductor 22 to a second terminal electrode and is connected to the second terminal electrode, and has an inductance value lower than that of the first conductor 22. A third conductor 32 exhibits a spiral shape, and is connected to a third terminal electrode. A fourth conductor 33 extends from a position corresponding to the internal end of the third conductor 32 to a fourth terminal electrode and is connected to the fourth terminal electrode, and has an inductance value lower than that of the third conductor 32. The second and fourth conductors 23, 33 are positioned between the first conductor 22 and the third conductor 32 in a stacked direction, and positioned between insulators 11 and 12, and between insulators 12 and 13 which are different from each other. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a laminated common mode filter.

  As this type of laminated common mode filter, a laminated body in which a plurality of insulators are laminated, first to fourth terminal electrodes formed in the laminated body, and disposed in the laminated body, are electrically connected to each other. A first coil including first and second conductors to be connected; and a second coil including third and fourth conductors disposed in the laminate and electrically connected to each other. There are known (see, for example, Patent Document 1).

Further, the multilayer common mode filter described in Patent Literature 1 describes the following configuration. The first conductor has a spiral shape and has an outer end connected to the first terminal electrode. The second conductor extends from the position corresponding to the inner end of the first conductor to the second terminal electrode and is connected to the second terminal electrode, and has an inductance value lower than that of the first conductor. The third conductor has a spiral shape and has an outer end connected to the third terminal electrode. The fourth conductor extends from the position corresponding to the inner end of the third conductor to the fourth terminal electrode and is connected to the fourth terminal electrode, and has an inductance value lower than that of the third conductor. The second and fourth conductors are located between the first conductor and the third conductor in the stacking direction of the plurality of insulators (hereinafter, simply referred to as “stacking direction” in some cases), and It is located between the same insulators among a plurality of insulators.
JP-A-8-203737 (Patent No. 3601619)

  In the multilayer common mode filter described in Patent Document 1, since the first and third conductors are spiral, the coil areas of the first and third conductors are relatively large. For this reason, if the first conductor and the third conductor are positioned close to each other in the stacking direction of the plurality of insulators, the stray capacitance generated between the first conductor and the third conductor increases. . When the stray capacitance increases, resonance occurs at a low frequency, and as a result, the high frequency characteristics are degraded.

  An object of the present invention is to provide a multilayer common mode filter capable of reducing the stray capacitance and improving the high frequency characteristics.

  A laminated common mode filter according to the present invention includes a laminated body in which a plurality of insulators are laminated, first to fourth terminal electrodes formed in the laminated body, and is disposed in the laminated body and electrically connected to each other. A first coil that includes first and second conductors connected to each other, and a second coil that is disposed in the laminate and includes third and fourth conductors that are electrically connected to each other. The first conductor has a spiral shape, the outer end is connected to the first terminal electrode, and the second conductor is connected to the second terminal from a position corresponding to the inner end of the first conductor. It extends to the electrode and is connected to the second terminal electrode, has an inductance value lower than that of the first conductor, the third conductor has a spiral shape, and the outer end portion is connected to the third terminal electrode And the fourth conductor corresponds to the inner end of the third conductor. To the fourth terminal electrode and connected to the fourth terminal electrode, the inductance value is lower than that of the third conductor, and the second and fourth conductors are arranged in the stacking direction of the plurality of insulators. It is located between one conductor and a third conductor, and is located between different insulators among a plurality of insulators.

  In the multilayer common mode filter according to the present invention, the second and fourth conductors are positioned between the first conductor and the third conductor in the stacking direction of the plurality of insulators, and the plurality of insulators Since the first conductor and the third conductor are located between different insulators, the distance between the first conductor and the third conductor in the stacking direction is relatively large. Compared with the multilayer common mode filter described in Patent Document 1, the distance between the first conductor and the third conductor in the stacking direction is located between the second conductor and the fourth conductor. Increases by the thickness of the insulator. Thereby, the stray capacitance generated between the first conductor and the third conductor can be reduced, and the high frequency characteristics can be improved.

  Preferably, the inner end portion of the first conductor and the inner end portion of the third conductor are positioned so as to be shifted from the stacking direction. In this case, the area of the overlapping area in the first coil (first conductor and second conductor) and the second coil (third conductor and fourth conductor) when viewed from the stacking direction is reduced. The stray capacitance generated between the first coil and the second coil can be reduced. As a result, the high frequency characteristics can be further improved.

  Preferably, the interval between the first conductor and the third conductor in the stacking direction is set to 20 μm or more. In this case, the stray capacitance generated between the first conductor and the third conductor can be reduced to about 3.4 pF or less.

  Preferably, among the plurality of insulators, the insulator located between the first conductor and the third conductor is a nonmagnetic material, and the remaining insulators are magnetic materials. In this case, the differential mode impedance is reduced, and a laminated common mode filter capable of supporting a high frequency band can be obtained.

  Preferably, the multilayer body includes a first part positioned so as to surround the first to fourth conductors, and a second part positioned so as to sandwich the first part in the stacking direction. Among the plurality of insulators, the insulator included in the first portion is a nonmagnetic material, and the remaining insulators are magnetic materials. In this case, the differential mode impedance is further reduced, and it is possible to obtain a laminated common mode filter that can cope with a higher frequency band.

  According to the present invention, it is possible to provide a stacked common mode filter capable of reducing stray capacitance and improving high frequency characteristics.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description, the same reference numerals are used for the same elements or elements having the same function, and redundant description is omitted. In the description, the terms “upper” and “lower” may be used, which correspond to the vertical direction of each figure.

  With reference to FIGS. 1 to 3, the configuration of the multilayer common mode filter CF according to the present embodiment will be described. FIG. 1 is a perspective view showing a multilayer common mode filter according to the present embodiment. FIG. 2 is a schematic diagram for explaining a cross-sectional configuration of the multilayer common mode filter according to the present embodiment. FIG. 3 is an exploded view of the element body included in the multilayer common mode filter according to the present embodiment.

  As shown in FIGS. 1 to 3, the multilayer common mode filter CF includes a rectangular parallelepiped element body 1, first and second coils 21 and 31, and a first element formed on a side surface of the element body 1. To fourth terminal electrodes 3 to 6. The first and second coils 21 and 31 are arranged in the element body 1. The first coil 21 is electrically connected to the first terminal electrode 3 and the second terminal electrode 4. The second coil 31 is electrically connected to the third terminal electrode 5 and the fourth terminal electrode 6. The first coil 21 and the second coil 31 are magnetically coupled to each other.

  As shown in FIG. 3, the element body 1 is a laminated body formed by laminating a plurality (9 layers in this embodiment) of insulators 11 to 19. The actual laminated common mode filter CF is integrated to such an extent that the boundaries between the insulators 11 to 19 cannot be visually recognized. The insulators 11 to 19 are configured by firing a green sheet.

  The first coil 21 has a first conductor 22 and a second conductor 23. The first conductor 22 is located on the insulator 11. The first conductor 22 has a spiral shape. The outer end portion of the first conductor 22 is drawn to the side surface of the element body 1 and exposed to the side surface, and is connected to the first terminal electrode 3. The outer end portion of the first conductor 22 functions as a lead conductor.

  A through-hole conductor 41 penetrating the insulator 11 in the thickness direction is formed at a position corresponding to the inner end portion of the first conductor 22 in the insulator 11. The first conductor 22 is electrically connected to the through-hole conductor 41 at its inner end.

  The second conductor 23 is located on the insulator 12. Thereby, the 1st conductor 22 and the 2nd conductor 23 will be located in a different layer. One end portion of the second conductor 23 is drawn to the side surface of the element body 1 (the side surface opposite to the side surface from which the outer end portion of the first conductor 22 is drawn) and exposed to the side surface, and the second terminal Connected to electrode 4. The other end of the second conductor 23 extends to a position where the through-hole conductor 41 is formed, that is, a position corresponding to the inner end of the first conductor 22. The second conductor 23 has a shorter line length and a lower inductance value than the first conductor 22. One end of the second conductor 23 functions as a lead conductor.

  The other end of the second conductor 23 is electrically connected to the through-hole conductor 41 in a state where the insulators 11 and 12 are laminated. As a result, the first conductor 22 and the second conductor 23 are electrically connected to each other to form the first coil 21.

  The second coil 31 has a third conductor 32 and a fourth conductor 33. The third conductor 32 is located on the insulator 14. The third conductor 32 has a spiral shape. The outer end portion of the third conductor 32 is drawn out to the side surface of the element body 1 (the side surface from which the outer end portion of the first conductor 22 is drawn) and is exposed to the side surface. Connected. The outer end portion of the third conductor 32 functions as a lead conductor.

  A through-hole conductor 43 that penetrates the insulator 13 in the thickness direction is formed at a position corresponding to the inner end portion of the third conductor 32 in the insulator 13. The through-hole conductor 43 is electrically connected to the inner end portion of the third conductor 32 in a state where the insulators 13 and 14 are laminated.

  The fourth conductor 33 is located on the insulator 13. Thereby, the 3rd conductor 32 and the 4th conductor 33 will be located in a different layer. One end portion of the fourth conductor 33 is drawn to the side surface of the element body 1 (the side surface opposite to the side surface from which the outer end portions of the first and third conductors 22 and 32 are drawn) and exposed to the side surface. , Connected to the fourth terminal electrode 6. The other end of the fourth conductor 33 extends to a position where the through-hole conductor 43 is formed, that is, a position corresponding to the inner end of the third conductor 32. The fourth conductor 33 has a shorter line length and a lower inductance value than the third conductor 32. One end of the fourth conductor 33 functions as a lead conductor.

  The other end of the fourth conductor 33 is electrically connected to the through-hole conductor 43 at one end thereof. As a result, the third conductor 32 and the fourth conductor 33 are electrically connected to each other to form the second coil 31.

  In the first conductor 22 and the third conductor 32, most of the spiral portions of the conductors 22 and 32 are viewed from the stacking direction of the insulators 11 to 19 (hereinafter simply referred to as “stacking direction”). It extends to overlap each other. In the present embodiment, the inner end of the first conductor 22 and the inner end of the third conductor 32 are at the same position when viewed from the stacking direction.

  In the multilayer common mode filter CF, as described above, the first conductor 22 is located on the insulator 11, the second conductor 23 is located on the insulator 12, and the fourth conductor 33 is the insulator 13. Located above, the third conductor 32 is located on the insulator 14. Therefore, the second conductor 23 and the fourth conductor 33 are located between the first conductor 22 and the third conductor 32 in the stacking direction. The second conductor 23 is located between the insulator 11 and the insulator 12, and the fourth conductor 33 is located between the insulator 12 and the insulator 13, and the second conductor 23 and the fourth conductor The conductor 33 is located between the different insulators 11 and 12 and between the insulators 12 and 13.

  Between the first conductor 22 and the third conductor 32, three layers of insulators 11, 12, and 13 exist. As a result, the first conductor 22 and the third conductor 32 are arranged with a gap G1 corresponding to the thickness of the three layers of insulators 11, 12, and 13 when viewed in the stacking direction. . The gap G1 between the first conductor 22 and the third conductor 32 is set to a length that allows the first coil 21 and the second 31 to be magnetically coupled. The distance G1 between the first conductor 22 and the third conductor 32 is preferably set to 80 μm or less. If the gap G1 between the first conductor 22 and the third conductor 32 is larger than 80 μm, the magnetic coupling between the first coil 21 and the second 31 becomes weak, and the characteristics as a common mode filter cannot be secured. It is.

  One layer of the insulator 12 exists between the second conductor 23 and the fourth conductor 33. As a result, the second conductor 23 and the fourth conductor 33 are arranged with a gap G2 corresponding to the thickness of the one-layer insulator 12 when viewed in the stacking direction.

  The insulators 15 to 17 are located on the insulator 11 and function as a base layer for protecting the first conductor 22. The insulators 18 and 19 are located under the insulator 14. The insulators 15 to 19 are also used to adjust the thickness of the element body 1 to a predetermined dimension. The number of insulators 15 to 17 is not limited to three layers, and may be one layer or two layers, or may be four or more layers. The insulators 18 and 19 are not limited to two layers and may not be stacked.

  Next, a method for manufacturing the stacked common mode filter CF will be described.

First, a non-magnetic green sheet that constitutes the insulators 11 to 13 is prepared. As the non-magnetic green sheet, for example, a slurry obtained by applying a slurry using a mixed powder of Fe ₂ O ₃ , ZnO and CuO as a raw material on a film by a doctor blade method can be used. The thickness of the nonmagnetic green sheet can be set to about 18 μm, for example. Instead of a mixed powder of Fe ₂ O ₃ , ZnO and CuO, a dielectric material (such as a mixed powder of TiO ₂ , CuO, NiO and MnCO) or an oxide ceramic material (Al ₂ O ₃ , SiO ₂ , ZrO) ₂ , forsterite, steatite, cordierite, or a mixed powder thereof) may be used.

  Moreover, the magnetic body green sheet which comprises the insulators 14-19 is prepared. The magnetic green sheet is a slurry made of, for example, ferrite (eg, Ni—Cu—Zn ferrite, Ni—Cu—Zn—Mg ferrite, Cu—Zn ferrite, or Ni—Cu ferrite) powder as a raw material. Can be used which is formed by coating the film by a doctor blade method. The thickness of the magnetic green sheet is, for example, about 20 μm.

  Next, through holes are formed by laser processing or the like at predetermined positions of the nonmagnetic green sheets constituting the insulators 11 and 13, that is, positions where the through hole conductors 41 and 43 are to be formed.

  Next, conductor patterns corresponding to the first to fourth conductors 22, 23, 32, and 33 are formed on each green sheet that constitutes the insulators 11 to 14. Each conductor pattern is formed, for example, by screen-printing a conductor paste (conductor material) mainly composed of silver or nickel and then drying. Each through hole is filled with a conductor paste when each conductor pattern is formed.

  Next, the green sheets are sequentially laminated and pressure-bonded, cut into chips, and then fired at a predetermined temperature (for example, 800 to 900 degrees). As a result, the element body 1 is formed. The element body 1 has, for example, a length in the longitudinal direction after completion of 1.25 mm, a width of 1.0 mm, and a height of 0.5 mm. The width of the first to fourth conductors 22, 23, 32, 33 after firing is set to about 50 μm, for example. The thickness of the first to fourth conductors 22, 23, 32, 33 after firing is set to about 12 μm, for example.

  Next, first to fourth terminal electrodes 3 to 6 are formed on the element body 1. Thereby, the laminated common mode filter CF is obtained. The first to fourth terminal electrodes 3 to 6 are baked at a predetermined temperature (for example, about 700 ° C.) after transferring an electrode paste mainly composed of silver, nickel, or copper to the outer surface of the element body 1, and further electric It is formed by plating. For electroplating, Cu / Ni / Sn, Ni / Sn, Ni / Au, Ni / Pd / Au, Ni / Pd / Ag, Ni / Ag, or the like can be used. The common mode impedance of the multilayer common mode filter CF can be set to 90Ω, for example.

  As described above, in the present embodiment, the second and fourth conductors 23 and 33 are located between the first conductor 22 and the third conductor 32 in the stacking direction and are different from each other. 12 and between the insulators 12 and 13, the distance between the first conductor 22 and the third conductor 32 in the stacking direction is relatively large. Compared with the multilayer common mode filter described in Patent Document 1, the distance between the first conductor 22 and the third conductor 32 in the stacking direction is between the second conductor 23 and the fourth conductor 33. The thickness is increased by the thickness of the insulator 12 positioned therebetween. Thereby, the stray capacitance generated between the first conductor 22 and the third conductor 23 can be reduced, and the high frequency characteristics of the multilayer common mode filter CF can be improved.

  A stray capacitance is also generated between the second conductor 23 and the fourth conductor 33. However, the first and third conductors 22 and 32 have a much larger conductor area than the second and fourth conductors 23 and 33, and the stray capacitance generated between the first coil 21 and the second coil 31 is The stray capacitance generated between the first conductor 22 and the third conductor 23 becomes dominant.

  By the way, in the multilayer common mode filter CF according to this embodiment, the insulators 11 to 13 positioned between the first conductor 22 and the third conductor 32 among the plurality of insulators 11 to 19 are nonmagnetic. And the remaining insulators 14 to 19 are magnetic bodies. The first conductor 22 and the third conductor 32 are also in contact with the magnetic material. Thereby, the impedance of the differential mode is reduced, and a common mode filter that can cope with a high frequency band can be obtained.

  In the present embodiment, the insulators 11 to 14 and 17 may be nonmagnetic materials, and the insulators 15, 16, 18 and 19 may be magnetic materials. In this case, as shown in FIG. 4, the first coil 21 (first and second conductors 22 and 23) and the second coil 31 (third and fourth conductors 32 and 33) in the element body 1. The insulators 11 to 14 and 17 included in the first portion 1a located so as to surround the first portion 1a are nonmagnetic materials, and the second portion 1b located so as to sandwich the insulators 11 to 14 and 17 in the stacking direction. The insulators 15, 16, 18, and 19 included are magnetic materials. That is, the conductors 22 and 23 of the first coil 21 and the conductors 32 and 33 of the second coil 31 are in contact with the nonmagnetic material. The first conductor 22 and the third conductor 32 do not contact the magnetic body. As a result, the differential mode impedance is further reduced, and a common mode filter that can cope with a higher frequency band can be obtained.

  Next, with reference to FIGS. 5 and 6, the configuration of a modified example of the multilayer common mode filter CF according to the present embodiment will be described. FIG. 5 is a schematic diagram for explaining a cross-sectional configuration of a modified example of the multilayer common mode filter according to the present embodiment. FIG. 6 is an exploded configuration diagram illustrating an element body included in a modification of the multilayer common mode filter according to the present embodiment. The multilayer common mode filter CF according to the modification is different from the multilayer common mode filter CF according to the embodiment described above with respect to the shapes of the first to fourth conductors 22, 23, 32, and 33.

  The multilayer common mode filter CF according to the modification is similar to the multilayer common mode filter CF shown in FIG. 1, the element body 1, the first and second coils 21, 31, and the first to fourth elements. Terminal electrodes 3 to 6 are provided. The first coil 21 has a first conductor 22 and a second conductor 23. The second coil 31 has a third conductor 32 and a fourth conductor 33.

  In the present modification, the inner end portion of the first conductor 22 and the inner end portion of the third conductor 32 are positioned so as to be shifted from the stacking direction. That is, the position of the through-hole conductor 41 and the position of the through-hole conductor 43 are deviated from the stacking direction. Thereby, in this modification, the stacking direction in the first coil 21 (first conductor 22 and second conductor 23) and the second coil 31 (third conductor 32 and fourth conductor 33). As a result, the area of the overlapping region is reduced. Thereby, the stray capacitance generated between the first coil 21 and the second coil 31 can be reduced. As a result, the high frequency characteristics of the multilayer common mode filter CF can be further improved.

  Here, the relationship between the gap G1 in the stacking direction of the first conductor 22 and the third conductor 32 and the stray capacitance CS generated between the first conductor 22 and the third conductor 32 will be described. To do.

  The present inventors conducted the following experiment in order to clarify the relationship between the gap G1 and the stray capacitance CS. That is, five samples (samples 1 to 5) of the stacked common mode filters having different intervals G1 were prepared, and the stray capacitance CS of each sample 1 to 5 was measured. The measurement results are shown in the table of FIG. Each sample 1 to 5 is designed so that the number of specimens is 60 and the common mode impedance is 90Ω.

  Sample 1 uses a stacked common mode filter having the same configuration as the stacked common mode filter CF of the present embodiment. The interval G1 was set to about 14 μm.

  Sample 2 was a stacked common mode filter having the same configuration as the stacked common mode filter CF of the present embodiment. The interval G1 was set to about 20 μm.

  For sample 3, a multilayer common mode filter having the same configuration as that of the multilayer common mode filter CF of the present embodiment was used. The interval G1 was set to about 30 μm.

  Sample 4 was a stacked common mode filter having the same configuration as the stacked common mode filter CF of the present embodiment. The interval G1 was set to about 40 μm.

  For Sample 5, a multilayer common mode filter having the same configuration as that of the multilayer common mode filter CF according to the modification of the present embodiment was used. The interval G1 was set to about 41 μm.

  As can be seen from the measurement results shown in FIG. 7, it can be seen that the stray capacitance CS can be reduced to about 3.4 pF or less by setting the gap G1 to 20 μm or more.

  The preferred embodiments of the present invention have been described above, but the present invention is not necessarily limited to these embodiments.

  In the present embodiment and the modification thereof, the first conductor 22 and the third conductor 32 are each one layer, but the present invention is not limited to this. In order to increase the impedance of each of the coils 21 and 31, the first and third conductors 22 and 32 may have two or more layers. In this case, the first and third conductors 22 and 32 having two or more layers are electrically connected through a through-hole conductor or the like.

  The first and third conductors 22 and 32 may be formed separately in portions that function as lead conductors and located in different layers. In this case, the first and third conductors 22 and 32 and the portion functioning as the lead conductor are electrically connected via a through-hole conductor or the like.

  The distance between the first conductor 22 and the second conductor 23, the distance between the second conductor 23 and the third conductor 32, and the distance between the third conductor 32 and the fourth conductor 33 are one layer. However, the present invention is not limited to this. Each interval may be an interval corresponding to the thickness of two or more insulators.

  The present invention can also be applied to a stacked common mode filter array having a plurality of sets of the first coil 21 and the second coil 31. Further, the present invention can be applied not only to the laminated common mode filter array manufactured by the green sheet laminating technique described above but also to the laminated common mode filter array manufactured by a printing technique, a thin film technique or the like.

It is a perspective view which shows the lamination type common mode filter which concerns on this embodiment. It is a schematic diagram for demonstrating the cross-sectional structure of the laminated | stacked common mode filter which concerns on this embodiment. It is the block diagram which decomposed | disassembled and showed the element body contained in the laminated | stacked common mode filter which concerns on this embodiment. It is a schematic diagram for demonstrating the cross-sectional structure of the laminated | stacked common mode filter which concerns on this embodiment. It is a schematic diagram for demonstrating the cross-sectional structure of the modification of the laminated | stacked common mode filter which concerns on this embodiment. It is the block diagram which decomposed | disassembled and showed the element | base_body included in the modification of the laminated | stacked common mode filter which concerns on this embodiment. It is a graph which shows the relationship between the space | interval in the lamination direction of a 1st conductor and a 3rd conductor, and the stray capacitance which generate | occur | produces between a 1st conductor and a 3rd conductor.

Explanation of symbols

  CF: multilayer common mode filter, 1 ... element body, 1a ... first part, 1b ... second part, 3-6 ... first to fourth terminal electrodes, 11-19 ... insulator, 21 ... first DESCRIPTION OF SYMBOLS 1 coil, 22 ... 1st conductor, 23 ... 2nd conductor, 31 ... 2nd coil, 32 ... 3rd conductor, 33 ... 4th conductor, 41, 43 ... Through-hole conductor.

Claims (5)

A laminate in which a plurality of insulators are laminated;
First to fourth terminal electrodes formed in the laminate;
A first coil disposed in the laminate and including first and second conductors electrically connected to each other;
A second coil that is disposed within the laminate and includes third and fourth conductors that are electrically connected to each other; and
The first conductor has a spiral shape, and an outer end is connected to the first terminal electrode,
The second conductor extends from a position corresponding to the inner end of the first conductor to the second terminal electrode and is connected to the second terminal electrode, and has an inductance greater than that of the first conductor. Low value,
The third conductor has a spiral shape and has an outer end connected to the third terminal electrode.
The fourth conductor extends from a position corresponding to the inner end of the third conductor to the fourth terminal electrode and is connected to the fourth terminal electrode, and has an inductance greater than that of the third conductor. Low value,
The second and fourth conductors are located between the first conductor and the third conductor in the stacking direction of the plurality of insulators, and between different insulators among the plurality of insulators. A laminated common mode filter characterized by being located in   2. The multilayer common mode filter according to claim 1, wherein an inner end portion of the first conductor and an inner end portion of the third conductor are shifted from each other as viewed from the stacking direction. .   The multilayer common mode filter according to claim 1 or 2, wherein an interval in the stacking direction between the first conductor and the third conductor is set to 20 µm or more.   The insulator positioned between the first conductor and the third conductor among the plurality of insulators is a non-magnetic body, and the remaining insulator is a magnetic body. The laminated common mode filter according to any one of claims 1 to 3. The multilayer body includes a first portion positioned so as to surround the first to fourth conductors, and a second portion positioned so as to sandwich the first portion in the stacking direction,
The insulator included in the first portion among the plurality of insulators is a non-magnetic body, and the remaining insulator is a magnetic body. The laminated common mode filter described in the paragraph.

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