JP2007150209A - Common mode filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a common mode filter which can reduce stray capacitance at a coil. <P>SOLUTION: The layer structure body 3 of the common mode filter is obtained by laminating a conductor layer 10, an insulating layer 11, a conductor layer 12, an insulating layer 13 and a conductor layer 14. The conductor layer 10 has a spiral coil conductor 16, a pull-out conductor 17 connected with the outer side end of the coil conductor 16, and a pull-out conductor 18 formed in the outer side area of the coil conductor 16. The conductor layer 12 has a spiral coil conductor 24, and a connection conductor 26 formed in the inner side area of the coil conductor 24. The conductor layer 14 has a spiral coil conductor 30. The inner side end of the coil conductor 16 and the pull-out conductor 18 are connected through the connection conductor 26. The connection conductor 26 is formed across the coil conductor 16. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a common mode filter having three coils.

Conventionally, as a common mode filter having a three-line structure having three coils, for example, as described in Patent Document 1, a plurality of insulating sheets and a plurality of coil conductor patterns are stacked to form three coils. A laminated common mode filter formed by forming is used. In such a three-line common mode filter, one of the three coils is used as a ground line coil, and the other two coils are used as signal line coils.
JP 2004-165448 A (FIGS. 3 and 4)

  However, in the above prior art, two spiral coil conductor patterns laminated via an insulating sheet are connected in series via via holes provided in the insulating sheet, thereby providing one ( 1 line) coil is formed. In such a configuration, since the area where the coil conductor patterns overlap each other in one line of coil is inevitably increased, it occurs between one end portion (input portion) and the other end portion (output portion) of the coil. Increases stray capacitance. As a result, the resonance frequency of the common mode filter is lowered, and the common mode characteristics in the high frequency band are lowered.

  An object of the present invention is to provide a common mode filter capable of reducing stray capacitance generated in a coil.

  The common mode filter of the present invention includes a spiral first coil conductor, a first conductor layer having a first lead conductor connecting the outer end of the first coil conductor and the first terminal electrode, and a spiral first coil conductor. A second conductor layer having a two-coil conductor, a second lead conductor connecting the outer end of the second coil conductor and the second terminal electrode, a spiral third coil conductor, and an outer end of the third coil conductor A third conductor layer having a third lead conductor connecting the first terminal electrode and the third terminal electrode; a first insulating layer disposed between the first conductor layer and the second conductor layer; a second conductor layer; A second insulating layer disposed between the three conductor layers, a first connecting means for connecting the inner end of the first coil conductor and the fourth terminal electrode, an inner end of the second coil conductor and the fifth terminal electrode A second connecting means for connecting the second coil, and an inner end of the third coil conductor and the sixth terminal electrode. Connecting means, wherein the first terminal electrode, the second terminal electrode, and the third terminal electrode are disposed on the same side, and the fourth terminal electrode, the fifth terminal electrode, and the sixth terminal electrode are the first terminal electrode, the second terminal electrode, The first connection means is disposed on the opposite side of the terminal electrode and the third terminal electrode, and the first connection means has a first connection portion formed to cross the first coil conductor in a layer different from the first conductor layer, The second connection means has a second connection portion formed so as to cross the second coil conductor in a layer different from the second conductor layer, and the third connection means is formed in a layer different from the third conductor layer. It has the 3rd connection part formed so that 3 coil conductors may be crossed, It is characterized by the above-mentioned.

  In such a common mode filter, the outer end of the first coil conductor is connected to the first terminal electrode via the first lead conductor, and the inner end of the first coil conductor includes a first connection portion. It is connected to the fourth terminal electrode through the connecting means. Thus, one (one line) coil including the first coil conductor is formed. The outer end of the second coil conductor is connected to the second terminal electrode via the second lead conductor, and the inner end of the second coil conductor is fifth via the second connecting means including the second connecting portion. Connected to terminal electrode. The outer end of the third coil conductor is connected to the third terminal electrode via the third lead conductor, and the inner end of the third coil conductor is connected to the sixth terminal electrode via the third connection means including the third connection portion. Connected. That is, since the coil including the second coil conductor and the coil including the third coil conductor are also formed, the common mode filter has a total of three coils.

  Here, the first connection portion is formed so as to cross the first coil conductor in a layer different from the first conductor layer. For this reason, in the coil including the first coil conductor, there are few regions where the first coil conductor and the first connection portion overlap. Similarly, in the coil including the second coil conductor, the region where the second coil conductor and the second connection portion overlap each other is small, and in the coil including the third coil conductor, the third coil conductor and the third connection portion. There are few areas where and overlap. As described above, since there is only a small area where the coil forming portions overlap each other in the coils of each line, the stray capacitance generated in each coil can be reduced.

  Preferably, the first conductor layer further includes a fourth lead conductor connected to the fourth terminal electrode, and the second conductor layer is formed in an inner region of the second coil conductor, and the inner end of the first coil conductor. And a fourth conductor for connecting the fourth lead conductor, and the fourth lead conductor and the first conductor for conductor constitute a part of the first connecting means, and the first conductor The connection portion is a connection conductor for the first coil conductor.

  By forming the connection conductor for the first coil conductor constituting a part of the first connection means in the second conductor layer, it is not necessary to increase the number of layers of the common mode filter more than necessary. Can be simplified. Further, by forming the connection conductor for the first coil conductor in the inner area of the second coil conductor in the second conductor layer, the coil including the first coil conductor can be formed with high space efficiency.

  In this case, preferably, the first conductor layer further includes a fifth lead conductor connected to the fifth terminal electrode and a sixth lead conductor connected to the sixth terminal electrode, and the fifth lead conductor is Part of the second connection means, the sixth lead conductor constitutes part of the third connection means, the second connection part is part of the fifth lead conductor, and the third connection part is 6 is a part of the lead conductor.

  By forming the fifth lead conductor constituting a part of the second connection means and the sixth lead conductor constituting a part of the third connection means on the first conductor layer, the layer of the common mode filter is further increased more than necessary. Therefore, the manufacturing process of the common mode filter can be further simplified.

  In this case, preferably, the first insulating layer includes two first contact holes that connect the inner end of the first coil conductor, the fourth lead conductor, and the connection conductor for the first coil conductor, and the second coil conductor. And a third contact hole connecting the inner end of the third coil conductor and the sixth lead conductor, and the second insulating layer includes a second contact hole connecting the inner end of the third lead conductor and the fifth lead conductor. A fourth contact hole connecting the inner end of the three-coil conductor and the sixth lead conductor; each first contact hole constitutes a part of the first connection means; and the second contact hole is a second connection hole The third contact hole and the fourth contact hole constitute a part of the third connection means.

  Thus, by providing contact holes for connection in the first insulating layer and the second insulating layer, the first connecting means, the second connecting means, and the third connecting means can be easily formed without complicating them. .

  The first conductor layer further includes a fifth lead conductor connected to the fifth terminal electrode, the third conductor layer further includes a sixth lead conductor connected to the sixth terminal electrode, The conductor layer is formed in an inner region of the second coil conductor, and further includes a connection conductor for a third coil conductor connecting the inner end of the third coil conductor and the sixth lead conductor, and the fifth lead conductor is The second connecting means constitutes a part, the sixth lead conductor and the connection conductor for the third coil conductor constitute a part of the third connecting means, and the second connection part is a part of the fifth lead conductor. Yes, the third connecting portion may be a connecting conductor for the third coil conductor.

  By forming the fifth lead conductor constituting the second connection means in the first conductor layer and forming the connection conductor for the third coil conductor constituting the third connection means in the second conductor layer, the common mode filter Since it is not necessary to increase the number of layers more than necessary, the manufacturing process of the common mode filter can be further simplified.

  In this case, preferably, the first insulating layer includes two first contact holes that connect the inner end of the first coil conductor, the fourth lead conductor, and the connection conductor for the first coil conductor, and the second coil conductor. A second contact hole connecting the inner end of the third lead conductor and the fifth lead conductor, and the second insulating layer includes the inner end of the third coil conductor and the sixth lead conductor and the connection conductor for the third coil conductor. There are two third contact holes to be connected to each other, each first contact hole constitutes a part of the first connection means, and the second contact hole constitutes a part of the second connection means. The three contact holes constitute a part of the third connection means.

  Thus, by providing contact holes for connection in the first insulating layer and the second insulating layer, the first connecting means, the second connecting means, and the third connecting means can be easily formed without complicating them. .

  The second conductor layer further includes a fifth lead conductor connected to the fifth terminal electrode, and the third conductor layer further includes a sixth lead conductor connected to the sixth terminal electrode. The conductor layer is formed in the outer region of the first coil conductor, and is formed in the outer region of the first coil conductor and the connection conductor for the second coil conductor that connects the inner end of the second coil conductor and the fifth lead conductor. And a connection conductor for a third coil conductor connecting the inner end of the third coil conductor and the sixth lead conductor, and the connection conductor for the fifth lead conductor and the second coil conductor is a second connection. The sixth lead conductor and the connection conductor for the third coil conductor constitute a part of the third connection means, and the second connection portion is a connection conductor for the second coil conductor. The third connection portion may be a connection conductor for a third coil conductor.

  By forming the connection conductor for the second coil conductor constituting the second connection means and the connection conductor for the third coil conductor constituting the third connection means on the first conductor layer, the layer of the common mode filter is further provided. Since it is not necessary to increase more than necessary, the manufacturing process of the common mode filter can be further simplified.

  In this case, preferably, the first insulating layer includes two first contact holes that connect the inner end of the first coil conductor, the fourth lead conductor, and the connection conductor for the first coil conductor, and the second coil conductor. Two second contact holes that respectively connect the inner end of the first conductor and the fifth lead conductor and the connection conductor for the second coil conductor, and the inner end of the third coil conductor and the connection for the sixth lead conductor and the third coil conductor. The second insulating layer has two third contact holes that respectively connect the conductors, and the second insulating layer connects the inner end of the third coil conductor and the sixth lead conductor and the connection conductor for the third coil conductor, respectively. Each of the first contact holes constitutes a part of the first connection means, and each second contact hole constitutes a part of the second connection means, and each third contact hole And each 4th Contact hole forms part of the third connection means.

  Thus, by providing contact holes for connection in the first insulating layer and the second insulating layer, the first connecting means, the second connecting means, and the third connecting means can be easily formed without complicating them. .

  Further preferably, the line length of at least one of the first coil conductor and the third coil conductor is shorter than the line length of the second coil conductor.

  Since the connection conductor for the first coil conductor is formed in the inner region of the second coil conductor in the second conductor layer, there is a limit to shortening the line length of the second coil conductor. The third coil conductor is not particularly limited. Therefore, for example, when the first coil conductor or the third coil conductor is used as the ground line, the DC resistance is lowered by making the line length of the coil conductor shorter than the line length of the second coil conductor. Therefore, good filter characteristics can be obtained.

  According to the present invention, stray capacitance generated in each coil of the common mode filter can be reduced. As a result, it is possible to improve the common mode characteristics in the high frequency band.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of a common mode filter according to the present invention will be described in detail with reference to the drawings.

  First, a first embodiment of a common mode filter according to the present invention will be described with reference to FIGS. FIG. 1 is a perspective view showing a common mode filter of the present embodiment. In the figure, a common mode filter 1 is a laminated common mode filter having a three-line structure.

  The common mode filter 1 includes a laminated body 5 including a lower magnetic substrate 2, a layer structure 3, and an upper magnetic substrate 4. The layer structure 3 is disposed between the lower magnetic substrate 2 and the upper magnetic substrate 4. The lower magnetic substrate 2 and the upper magnetic substrate 4 are substrates made of a magnetic material such as sintered ferrite or composite ferrite (resin containing powdered ferrite).

  Terminal electrodes 6 </ b> A to 8 </ b> A are provided on one side surface of the stacked body 5, and terminal electrodes 6 </ b> B to 8 </ b> B are provided on the other side surface of the stacked body 5. The terminal electrode 6A is disposed between the terminal electrodes 7A and 8A, and the terminal electrode 6B is disposed between the terminal electrodes 7B and 8B. The terminal electrodes 6 </ b> A to 8 </ b> A and the terminal electrodes 6 </ b> B to 8 </ b> B are formed in a U shape so as to cover the lower surface, the side surface, and the upper surface of the multilayer body 5.

  FIG. 2 is an exploded perspective view of the laminate 5. In the figure, the layer structure 3 is formed by laminating an insulating layer 9, a conductor layer 10, an insulating layer 11, a conductor layer 12, an insulating layer 13, a conductor layer 14 and an insulating layer 15 in order from the bottom. The insulating layers 9, 11, 13, and 15 are formed of a resin material (for example, polyimide resin or epoxy resin) that is excellent in electrical and magnetic insulation and has good workability. The conductor layers 10, 12, and 14 are formed of a metal material (for example, Cu, Al, etc.) excellent in conductivity and workability.

  The lowermost insulating layer 9 is a layer for improving the adhesiveness with the conductor layer 10 even when the upper surface of the lower magnetic substrate 2 is uneven.

  The conductor layer 10 is formed on the insulating layer 9. As shown in FIG. 3, the conductor layer 10 includes a rectangular spiral coil conductor 16, a lead conductor 17 connected to the coil conductor 16, and lead conductors 18 to 20 formed in an outer region of the coil conductor 16. have. Further, the conductor layer 10 has extraction electrodes 21A to 23A formed on one side edge of the insulating layer 9, and extraction electrodes 21B to 23B formed on the other side edge of the insulating layer 9. is doing. The extraction electrode 21A is disposed between the extraction electrodes 22A and 23A, and the extraction electrode 21B is disposed between the extraction electrodes 22B and 23B.

  One end of the lead conductor 17 is connected to the outer end of the coil conductor 16, and the other end of the lead conductor 17 is connected to the lead electrode 21A. The lead conductors 18 to 20 extend in a bent shape and are connected to the lead electrodes 21B to 23B, respectively. The leading end portions of the lead conductors 18 to 20 (end portions opposite to the lead electrodes 21 </ b> B to 23 </ b> B) are located on one side of the coil conductor 16.

  The conductor layer 12 is formed on the insulating layer 11. As shown in FIG. 4, the conductor layer 12 has a rectangular spiral coil conductor 24, a lead conductor 25 connected to the coil conductor 24, and a connection conductor 26 formed in an inner region of the coil conductor 24. is doing. The conductor layer 12 has lead electrodes 27A to 29A formed on one side edge of the insulating layer 11, and lead electrodes 27B to 29B formed on the other side edge of the insulating layer 11. is doing. The extraction electrode 27A is disposed between the extraction electrodes 28A and 29A, and the extraction electrode 27B is disposed between the extraction electrodes 28B and 29B.

  One end of the lead conductor 25 is connected to the outer end of the coil conductor 24, and the other end of the lead conductor 25 is connected to the lead electrode 28A. The connection conductor 26 is a conductor for connecting the inner end of the coil conductor 16 in the conductor layer 10 and the lead conductor 18.

  The conductor layer 14 is formed on the insulating layer 13. As shown in FIG. 5, the conductor layer 14 includes a rectangular spiral coil conductor 30 and a lead conductor 31 connected to the coil conductor 30. The conductor layer 14 has extraction electrodes 32A to 34A formed on one side edge of the insulating layer 13 and extraction electrodes 32B to 34B formed on the other side edge of the insulating layer 13. is doing. The extraction electrode 32A is disposed between the extraction electrodes 33A and 34A, and the extraction electrode 32B is disposed between the extraction electrodes 33B and 34B. One end of the lead conductor 31 is connected to the outer end of the coil conductor 30, and the other end of the lead conductor 31 is connected to the lead electrode 34A.

  Here, as shown in FIG. 6A, the connection conductor 26 of the conductor layer 12 is formed so as to cross the coil conductor 16 of the conductor layer 10 vertically. The straight portion 19a on the leading end side of the lead conductor 19 in the conductor layer 10 is formed so as to cross the coil conductor 24 of the conductor layer 12 vertically as shown in FIG. 6B. The straight portion 20a on the leading end side of the lead conductor 20 in the conductor layer 10 is formed so as to cross the coil conductor 30 of the conductor layer 14 vertically as shown in FIG. 6C.

  The line length of the coil conductor 16 is shorter than the line length of the coil conductors 24 and 30. For this reason, the lead conductors 18 to 20 can be provided in the outer region of the coil conductor 16 in the conductor layer 10.

  In the insulating layer 11, a contact hole 35 a that connects the inner end of the coil conductor 16 and one end of the connection conductor 26, a contact hole 35 b that connects the other end of the connection conductor 26 and the lead conductor 18, and the coil conductor 24 A contact hole 35c that connects the inner end and the lead conductor 19 and a contact hole 35d that connects the inner end of the coil conductor 30 and the lead conductor 20 are formed. The contact holes 35 a to 35 d are formed by embedding a magnetic material such as silver or palladium in a through hole provided in the insulating layer 11.

  In addition, a contact hole 36 that connects the inner end of the coil conductor 30 and the lead conductor 20 is formed in the insulating layer 13. The structure of the contact hole 36 is the same as that of the contact holes 35a to 35d.

  In addition to forming the connection conductor 26 in the inner region of the coil conductor 24, by providing such contact holes 35a to 35d, 36, the electrical connection between the coil conductor 16 and the lead conductor 18, the coil conductor 24 and the lead The electrical connection with the conductor 19 and the electrical connection between the coil conductor 30 and the lead conductor 20 can be performed in a space efficient and simple configuration.

  As described above, the terminal electrodes 6A to 8A and the terminal electrodes 6B to 8B are provided on both side surfaces of the multilayer body 5 configured as described above. The terminal electrode 6A is electrically connected to the extraction electrodes 21A, 27A, 32A, the terminal electrode 7A is electrically connected to the extraction electrodes 22A, 28A, 33A, and the terminal electrode 8A is electrically connected to the extraction electrodes 23A, 29A, 34A. It is connected to the. The terminal electrode 6B is electrically connected to the extraction electrodes 21B, 27B, 32B, the terminal electrode 7B is electrically connected to the extraction electrodes 22B, 28B, 33B, and the terminal electrode 8B is electrically connected to the extraction electrodes 23B, 29B, 34B. It is connected to the.

  In the common mode filter 1 as described above, the terminal electrode 6A, the extraction electrode 21A, the extraction conductor 17, the coil conductor 16, the contact hole 35a, the connection conductor 26, the contact hole 35b, the extraction conductor 18, the extraction electrode 21B, and the terminal electrode 6B are The coil 37A is configured to be electrically connected in series. The terminal electrode 7A, the extraction electrode 28A, the extraction conductor 25, the coil conductor 24, the contact hole 35c, the extraction conductor 19, the extraction electrode 22B, and the terminal electrode 7B constitute a coil 37B that is electrically connected in series. The terminal electrode 8A, the extraction electrode 34A, the extraction conductor 31, the coil conductor 30, the contact holes 36 and 35d, the extraction conductor 20, the extraction electrode 23B, and the terminal electrode 8B constitute a coil 37C that is electrically connected in series. . Thereby, the common mode filter 1 has three coils 37A to 37C.

  The terminal electrodes 6A to 8A are used as input electrodes for the coils 37A to 37C, respectively, and the terminal electrodes 6B to 8B are used as output electrodes for the coils 37A to 37C, respectively. The coil 37A is configured as a ground (GND) line coil, and the coils 37B and 37C are configured as signal line coils.

  Here, in the coil 37 </ b> A, the connection conductor 26 is formed so as to cross the coil conductor 16, and therefore, there are very few regions that overlap vertically with the insulating layer 11 interposed therebetween. Further, in the coil 37B, since the straight portion 19a on the distal end side of the lead conductor 19 is formed so as to cross the coil conductor 24, there are very few regions that overlap vertically with the insulating layer 11 in between. Further, in the coil 37C, since the straight portion 20a on the leading end side of the lead conductor 20 is formed so as to cross the coil conductor 30, there are very few regions overlapping vertically with the insulating layers 11 and 13 therebetween.

  Next, a procedure for manufacturing the above-described common mode filter 1 will be described. First, the laminated body 5 is produced as follows.

  That is, the insulating layer 9 is formed by applying and curing the above resin material on the lower magnetic substrate 2 by, for example, spin coating, dipping, spraying, or the like. Subsequently, a conductive thin film is formed on the insulating layer 9 by, for example, electroplating or sputtering, and further the pattern of the coil conductor 16, the lead conductors 17 to 20, the lead electrodes 21A to 23A and the lead electrodes 21B to 23B is formed by photolithography. By forming the conductor layer 10, the conductor layer 10 is formed. In addition, as a formation method of the conductor layer 10, you may use a lamination | stacking construction method etc. other than said thin film construction method.

  Subsequently, the insulating layer 11 is formed on the conductor layer 10 in the same manner as the method for forming the insulating layer 9. Then, contact holes 35a to 35d are formed in the insulating layer 11 by, for example, an etching method and an electroplating method. Subsequently, by forming a pattern of the coil conductor 24, the lead conductor 25, the connection conductor 26, the lead electrodes 27 </ b> A to 29 </ b> A and the lead electrodes 27 </ b> B to 29 </ b> B on the insulating layer 11 by a method similar to the method for forming the conductor layer 10. The conductor layer 12 is formed.

  Subsequently, in the same manner as the method for forming the insulating layer 11, the insulating layer 13 is formed on the conductor layer 12, and the contact hole 36 is further formed in the insulating layer 13. Subsequently, by forming a pattern of the coil conductor 30, the lead conductor 31, the lead electrodes 32A to 34A and the lead electrodes 32B to 34B on the insulating layer 13 by a method similar to the method for forming the conductor layers 10 and 12, the conductors Layer 14 is formed.

  Subsequently, the insulating layer 15 is formed on the conductor layer 14 in the same manner as the method for forming the insulating layer 9. Subsequently, an adhesive such as an epoxy resin is applied on the insulating layer 15 to form an adhesive layer (not shown), and the upper magnetic substrate 4 is attached to the upper surface of the adhesive layer. Thereby, said laminated body 5 is obtained.

  Thereafter, the terminal electrodes 6 </ b> A to 8 </ b> A are formed on one side surface portion of the multilayer body 5, and the terminal electrodes 6 </ b> B to 8 </ b> B are formed on the other side surface portion of the multilayer body 5. Specifically, for example, a Cr / Cu film or a Ti / Cu film is formed on the side surface of the laminate 5 by mask sputtering, and then electroplating is performed using Ni / Sn, whereby the terminal electrodes 6A to 8A. And the terminal electrodes 6B-8B are formed. As described above, the common mode filter 1 is completed.

  As described above, in the present embodiment, since there is only a small overlapping region in one line of the coil 37A, it occurs between the terminal electrodes 6A and 6B (between the input portion and the output portion of the coil 37A). The stray capacitance can be reduced. Similarly, stray capacitance generated between the terminal electrodes 7A and 7B of the coil 37B can be reduced, and stray capacitance generated between the terminal electrodes 8A and 8B of the coil 37C can be reduced. Thereby, it is possible to increase the resonance frequency of the common mode filter 1 and obtain the common mode filter 1 having good high frequency characteristics.

  Further, since the line length of the coil conductor 16 used as the ground line is shorter than the line length of the coil conductors 24 and 30 used as the signal line, the DC resistance can be kept low. As a result, it is possible to realize the common mode filter 1 having a three-line structure with excellent characteristics.

  Furthermore, since a part of the coil 37A is provided on the conductor layer 12, a part of the coil 37B is provided on the conductor layer 10, and a part of the coil 37C is provided on the conductor layer 10, even if there are only three conductor layers. Three coils can be formed. Thereby, since the manufacturing process of the common mode filter 1 can be simplified, the manufacturing cost can be suppressed. Moreover, since the height dimension of the common mode filter 1 can be reduced, it is advantageous for downsizing of the element.

  A second embodiment of a common mode filter according to the present invention will be described with reference to FIGS. In the figure, the same or equivalent members as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  FIG. 7 is an exploded perspective view showing the main part of the common mode filter of the present embodiment. In the figure, the common mode filter laminate 5 of the present embodiment has a layer structure 40 instead of the layer structure 3 of the first embodiment. The layer structure 40 is formed by laminating the insulating layer 9, the conductor layer 41, the insulating layer 42, the conductor layer 43, the insulating layer 44, the conductor layer 45, and the insulating layer 15 in order from the bottom.

  The conductor layer 41 is formed on the insulating layer 9. As shown in FIG. 8, the conductor layer 41 includes a rectangular spiral coil conductor 46, a lead conductor 47 connected to the coil conductor 46, and lead conductors 48 and 49 formed in an outer region of the coil conductor 46. And extraction electrodes 21A to 23A and extraction electrodes 21B to 23B.

  One end of the lead conductor 47 is connected to the outer end of the coil conductor 46, and the other end of the lead conductor 47 is connected to the lead electrode 21A. The lead conductors 48 and 49 extend in a bent shape and are connected to the lead electrodes 21B and 22B, respectively. The leading end portions of the lead conductors 48 and 49 (end portions opposite to the lead electrodes 21B and 22B) are located on one side of the coil conductor 46.

  The conductor layer 43 is formed on the insulating layer 42. As shown in FIG. 9, the conductor layer 43 includes a rectangular spiral coil conductor 50, a lead conductor 51 connected to the coil conductor 50, and connection conductors 52 and 53 formed in an inner region of the coil conductor 50. And extraction electrodes 27A to 29A and extraction electrodes 27B to 29B.

  One end of the lead conductor 51 is connected to the outer end of the coil conductor 50, and the other end of the lead conductor 51 is connected to the lead electrode 28A. The connection conductor 52 is a conductor for connecting the inner end of the coil conductor 46 in the conductor layer 41 and the lead conductor 48. The connection conductor 53 will be described later.

  The conductor layer 45 is formed on the insulating layer 44. As shown in FIG. 10, the conductor layer 45 includes a rectangular spiral coil conductor 54, a lead conductor 55 connected to the coil conductor 54, a lead conductor 56 formed in the outer region of the coil conductor 54, and a lead It has electrodes 32A to 34A and extraction electrodes 32B to 34B.

  One end of the lead conductor 55 is connected to the outer end of the coil conductor 54, and the other end of the lead conductor 55 is connected to the lead electrode 34A. The lead conductor 56 extends in a bent shape and is connected to the lead electrode 34B. The leading end of the lead conductor 56 is located on the same side as the leading ends of the lead conductors 48 and 49 with respect to the coil conductor 54.

  The connection conductor 53 formed on the conductor layer 43 is a conductor for connecting the inner end of the coil conductor 54 and the lead conductor 56.

  Here, the connection conductor 52 of the conductor layer 43 is formed so as to cross the coil conductor 46 of the conductor layer 41 vertically as shown in FIG. The straight portion 49a on the leading end side of the lead conductor 49 in the conductor layer 41 is formed so as to cross the coil conductor 50 of the conductor layer 43 vertically as shown in FIG. As shown in FIG. 11C, the connection conductor 53 of the conductor layer 43 is formed so as to cross the coil conductor 54 of the conductor layer 45 vertically.

  The line length of the coil conductor 46 is shorter than the line length of the coil conductor 50. Therefore, the lead conductors 48 and 49 can be provided in the outer region of the coil conductor 46 in the conductor layer 41.

  In the insulating layer 42, a contact hole 57 a that connects the inner end of the coil conductor 46 and one end of the connection conductor 52, a contact hole 57 b that connects the other end of the connection conductor 52 and the lead conductor 48, and the coil conductor 50 A contact hole 57c that connects the inner end and the lead conductor 49 is formed.

  In the insulating layer 44, a contact hole 58 a that connects the inner end of the coil conductor 54 and one end of the connection conductor 53, and a contact hole 58 b that connects the other end of the connection conductor 53 and the lead conductor 56 are formed. .

  In the common mode filter of the present embodiment as described above, the terminal electrode 6A, the extraction electrode 21A, the extraction conductor 47, the coil conductor 46, the contact hole 57a, the connection conductor 52, the contact hole 57b, the extraction conductor 48, the extraction electrode 21B, and the terminal The electrode 6B constitutes a coil 59A that is electrically connected in series. The terminal electrode 7A, the extraction electrode 28A, the extraction conductor 51, the coil conductor 50, the contact hole 57c, the extraction conductor 49, the extraction electrode 22B, and the terminal electrode 7B constitute a coil 59B that is electrically connected in series. The terminal electrode 8A, the extraction electrode 34A, the extraction conductor 55, the coil conductor 54, the contact hole 58a, the connection conductor 53, the contact hole 58b, the extraction conductor 56, the extraction electrode 34B, and the terminal electrode 8B are electrically connected in series. 59C is configured.

  Here, in the coil 59A, since the connection conductor 52 is formed so as to cross the coil conductor 46, there are very few regions that overlap vertically with the insulating layer 42 interposed therebetween. Further, in the coil 59B, since the straight portion 49a on the distal end side of the lead conductor 49 is formed so as to cross the coil conductor 50, there are very few regions overlapping vertically with the insulating layer 42 interposed therebetween. Further, in the coil 59C, since the connection conductor 53 is formed so as to cross the coil conductor 54, there are very few regions that overlap vertically with the insulating layer 44 interposed therebetween. Thereby, the stray capacitance generated in each line of the coils 59A to 59C can be reduced as in the first embodiment.

  A third embodiment of a common mode filter according to the present invention will be described with reference to FIGS. In the figure, the same or equivalent members as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  FIG. 12 is an exploded perspective view showing a main part of the common mode filter of the present embodiment. In the figure, the laminate 5 of the common mode filter of this embodiment has a layer structure 60 instead of the layer structure 3 in the first embodiment. The layer structure 60 is formed by laminating the insulating layer 9, the conductor layer 61, the insulating layer 62, the conductor layer 63, the insulating layer 64, the conductor layer 65, and the insulating layer 15 in order from the bottom.

  The conductor layer 61 is formed on the insulating layer 9. As shown in FIG. 13, the conductor layer 61 includes a rectangular spiral coil conductor 66, a lead conductor 67 connected to the coil conductor 66, a lead conductor 68 and a connection conductor formed in an outer region of the coil conductor 66. 69, 70, extraction electrodes 21A to 23A, and extraction electrodes 21B to 23B.

  One end of the lead conductor 67 is connected to the outer end of the coil conductor 66, and the other end of the lead conductor 67 is connected to the lead electrode 21A. The lead conductor 68 extends in a bent shape and is connected to the lead electrode 21B. The leading end of the lead conductor 68 (the end opposite to the lead electrode 21 </ b> B) and the connection conductor 69 are located on one side of the coil conductor 66, and the connection conductor 70 sandwiches the coil conductor 66. It is located on the opposite side of 69.

  The conductor layer 63 is formed on the insulating layer 62. As shown in FIG. 14, the conductor layer 63 includes a rectangular spiral coil conductor 71, a lead conductor 72 connected to the coil conductor 71, a connection conductor 73 formed in an inner region of the coil conductor 71, a coil It has an extraction conductor 74 formed in the outer region of the conductor 71, extraction electrodes 27A to 29A, and extraction electrodes 27B to 29B.

  One end of the lead conductor 72 is connected to the outer end of the coil conductor 71, and the other end of the lead conductor 72 is connected to the lead electrode 28A. The connection conductor 73 is a conductor for connecting the inner end of the coil conductor 66 and the lead conductor 68 in the conductor layer 63. The leading end portion of the lead conductor 74 is located on the same side as the connection conductor 69 with respect to the coil conductor 71.

  The conductor layer 65 is formed on the insulating layer 64. As shown in FIG. 15, the conductor layer 65 includes a rectangular spiral coil conductor 75, a lead conductor 76 connected to the coil conductor 75, a lead conductor 77 formed in the outer region of the coil conductor 75, and a lead It has electrodes 32A to 34A and extraction electrodes 32B to 34B.

  One end of the lead conductor 76 is connected to the outer end of the coil conductor 75, and the other end of the lead conductor 76 is connected to the lead electrode 34A. The lead conductor 77 extends in a bent shape and is connected to the lead electrode 34B. The leading end of the lead conductor 77 is located on the same side as the connection conductor 70 with respect to the coil conductor 75.

  The connection conductor 69 formed on the conductor layer 61 is a conductor for connecting the inner end of the coil conductor 71 and the lead conductor 74 in the conductor layer 63. The connection conductor 70 formed in the conductor layer 61 is a conductor for connecting the inner end of the coil conductor 75 in the conductor layer 65 and the lead conductor 77.

  Here, the connection conductor 73 of the conductor layer 63 is formed so as to cross the coil conductor 66 of the conductor layer 61 vertically as shown in FIG. As shown in FIG. 16B, the connection conductor 69 of the conductor layer 61 is formed so as to cross the coil conductor 71 of the conductor layer 63 vertically. The connection conductor 70 of the conductor layer 61 is formed so as to cross the coil conductor 75 of the conductor layer 65 vertically as shown in FIG.

  The line length of the coil conductor 66 is shorter than the line length of the coil conductors 71 and 75. For this reason, the connection conductors 69 and 70 can be provided in regions on both sides of the coil conductor 66 in the conductor layer 61, respectively.

  In the insulating layer 62, a contact hole 78 a that connects the inner end of the coil conductor 66 and one end of the connection conductor 73, a contact hole 78 b that connects the other end of the connection conductor 73 and the lead conductor 68, and the coil conductor 71 A contact hole 78c that connects the inner end and one end of the connection conductor 69, a contact hole 78d that connects the other end of the connection conductor 69 and the lead conductor 74, an inner end of the coil conductor 75, and one end of the connection conductor 70 A contact hole 78e to be connected and a contact hole 78f to connect the other end of the connection conductor 70 and the lead conductor 77 are formed.

  In the insulating layer 64, a contact hole 79 a that connects the inner end of the coil conductor 75 and one end of the connection conductor 70 and a contact hole 79 b that connects the other end of the connection conductor 70 and the lead conductor 77 are formed. .

  In the common mode filter of the present embodiment as described above, the terminal electrode 6A, the extraction electrode 21A, the extraction conductor 67, the coil conductor 66, the contact hole 78a, the connection conductor 73, the contact hole 78b, the extraction conductor 68, the extraction electrode 21B, and the terminal The electrode 6B constitutes a coil 80A that is electrically connected in series. The terminal electrode 7A, the extraction electrode 28A, the extraction conductor 72, the coil conductor 71, the contact hole 78c, the connection conductor 69, the contact hole 78d, the extraction conductor 74, the extraction electrode 28B, and the terminal electrode 7B are electrically connected in series. 80B is configured. Terminal electrode 8A, extraction electrode 34A, extraction conductor 76, coil conductor 75, contact holes 79a and 78e, connection conductor 70, contact holes 78f and 79b, extraction conductor 77, extraction electrode 34B and terminal electrode 8B are electrically connected in series. This constitutes the coil 80C.

  Here, in the coil 80A, since the connection conductor 73 is formed so as to cross the coil conductor 66, there are very few regions that overlap vertically with the insulating layer 62 interposed therebetween. Further, in the coil 80B, since the connection conductor 69 is formed so as to cross the coil conductor 71, there are very few regions that overlap vertically with the insulating layer 62 interposed therebetween. Further, in the coil 80C, since the connection conductor 70 is formed so as to cross the coil conductor 75, there are very few regions that overlap vertically with the insulating layers 62 and 64 interposed therebetween. Thereby, the stray capacitance generated in each line of the coils 80A to 80C can be reduced as in the first embodiment.

  The present invention is not limited to the above embodiment. For example, the structure in which three coils are formed using a coil conductor, a lead conductor, and a connection conductor is not particularly limited to the above three embodiments.

  In the above embodiment, the lead conductor and the connection conductor are formed in any one of the three conductor layers having the coil conductor. However, the lead conductor and the connection conductor may be formed in a layer completely different from the conductor layer having the coil conductor. . Further, as means for connecting the inner end of the coil conductor and the corresponding terminal electrode, other than the structure in which the contact hole is provided in the insulating layer, for example, a lead wire or the like may be used.

  In the above embodiment, the coil conductor formed in the conductor layer has a rectangular spiral shape. However, the spiral shape of the coil conductor may be a circular shape or an elliptical shape.

It is a perspective view which shows 1st Embodiment of the common mode filter concerning this invention. It is a disassembled perspective view of the laminated body shown in FIG. It is a top view which shows the 1st conductor layer from the bottom shown in FIG. It is a top view which shows the 2nd conductor layer from the bottom shown in FIG. FIG. 3 is a plan view showing a third conductor layer from the bottom shown in FIG. 2. It is a schematic plan view which shows the positional relationship of the coil conductor shown in FIGS. 3-5 and the conductor which crosses this coil conductor. It is a disassembled perspective view which shows the laminated body which is the principal part of 2nd Embodiment of the common mode filter concerning this invention. It is a top view which shows the 1st conductor layer from the bottom shown in FIG. It is a top view which shows the 2nd conductor layer from the bottom shown in FIG. It is a top view which shows the 3rd conductor layer from the bottom shown in FIG. It is a schematic plan view which shows the positional relationship of the coil conductor shown in FIGS. 8-10, and the conductor which crosses this coil conductor. It is a disassembled perspective view which shows the laminated body which is the principal part of 3rd Embodiment of the common mode filter concerning this invention. It is a top view which shows the 1st conductor layer from the bottom shown in FIG. It is a top view which shows the 2nd conductor layer from the bottom shown in FIG. FIG. 13 is a plan view showing a third conductor layer from the bottom shown in FIG. 12. It is a schematic plan view which shows the positional relationship of the coil conductor shown in FIGS. 13-15, and the conductor which crosses this coil conductor.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Common mode filter, 6A ... Terminal electrode (1st terminal electrode), 6B ... Terminal electrode (4th terminal electrode), 7A ... Terminal electrode (2nd terminal electrode), 7B ... Terminal electrode (5th terminal electrode), 8A ... terminal electrode (third terminal electrode), 8B ... terminal electrode (sixth terminal electrode), 10 ... conductor layer (first conductor layer), 11 ... insulating layer (first insulating layer), 12 ... conductor layer (first) 2 conductor layers), 13 ... insulating layer (second insulating layer), 14 ... conductor layer (third conductor layer), 16 ... coil conductor (first coil conductor), 17 ... lead conductor (first lead conductor), 18 ... Leader (fourth lead conductor, first connecting means), 19 ... Leader conductor (fifth lead conductor, second connecting means), 19a ... Straight line part (second connecting part), 20 ... Leader conductor (sixth lead) Conductor, third connecting means), 20a ... straight line portion (third connecting portion), 24 ... coil conductor (second coil conductor), 2 ... Lead conductor (second lead conductor), 26 ... Connection conductor (connection conductor for the first coil conductor, first connection portion, first connection means), 30 ... Coil conductor (third coil conductor), 31 ... Lead conductor (Third lead conductor), 35a, 35b ... contact hole (first contact hole, first connecting means), 35c ... contact hole (second contact hole, second connecting means), 35d ... contact hole (third contact hole) , Third connecting means), 36 ... contact hole (fourth contact hole, third connecting means), 41 ... conductor layer (first conductor layer), 42 ... insulating layer (first insulating layer), 43 ... conductor layer ( Second conductor layer), 44 ... insulating layer (second insulating layer), 45 ... conductor layer (third conductor layer), 46 ... coil conductor (first coil conductor), 47 ... lead conductor (first lead conductor), 48 ... Lead conductor (fourth lead conductor) , First connection means), 49... Extraction conductor (fifth extraction conductor, second connection means), 49 a... Linear portion (second connection portion), 50... Coil conductor (second coil conductor), 51. Second conductor), 52... Connecting conductor (connecting conductor for the first coil conductor, first connecting portion, first connecting means), 53... Connecting conductor (connecting conductor for the third coil conductor, third connecting portion) (Third connecting means), 54 ... coil conductor (third coil conductor), 55 ... lead conductor (third lead conductor), 56 ... lead conductor (sixth lead conductor, third connecting means), 57a, 57b ... contact holes (1st contact hole, 1st connection means), 57c ... Contact hole (2nd contact hole, 2nd connection means), 58a, 58b ... Contact hole (3rd contact hole, 3rd connection means), 61 ... Conductor layer (First conductor layer), 62. Edge layer (first insulating layer), 63 ... conductor layer (second conductor layer), 64 ... insulating layer (second insulating layer), 65 ... conductor layer (third conductor layer), 66 ... coil conductor (first coil) Conductor), 67 ... lead conductor (first lead conductor), 68 ... lead conductor (fourth lead conductor, first connecting means), 69 ... connection conductor (connecting conductor for second coil conductor, second connecting portion, second conductor 2 connection means), 70 ... connection conductor (connection conductor for third coil conductor, third connection portion, third connection means), 71 ... coil conductor (second coil conductor), 72 ... lead conductor (second lead conductor) , 73 ... Connection conductor (connection conductor for first coil conductor, first connection portion, first connection means), 74 ... Lead conductor (fifth lead conductor, second connection means), 75 ... Coil conductor (third Coil conductor), 76 ... lead conductor (third lead conductor), 77 ... lead conductor (sixth lead conductor, third connecting means), 78 78b, contact holes (first contact hole, first connection means), 78c, 78d, contact holes (second contact hole, second connection means), 78e, 78f, contact holes (third contact hole, third connection). Means), 79a, 79b ... contact holes (fourth contact hole, third connection means).

Claims (9)

A first conductor layer having a spiral first coil conductor and a first lead conductor connecting the outer end of the first coil conductor and the first terminal electrode;
A second conductor layer having a spiral second coil conductor, and a second lead conductor connecting the outer end of the second coil conductor and the second terminal electrode;
A third conductor layer having a spiral third coil conductor and a third lead conductor connecting the outer end of the third coil conductor and the third terminal electrode;
A first insulating layer disposed between the first conductor layer and the second conductor layer;
A second insulating layer disposed between the second conductor layer and the third conductor layer;
First connection means for connecting an inner end of the first coil conductor and a fourth terminal electrode;
Second connection means for connecting the inner end of the second coil conductor and a fifth terminal electrode;
A third connecting means for connecting the inner end of the third coil conductor and the sixth terminal electrode;
The first terminal electrode, the second terminal electrode and the third terminal electrode are disposed on the same side;
The fourth terminal electrode, the fifth terminal electrode, and the sixth terminal electrode are disposed on opposite sides of the first terminal electrode, the second terminal electrode, and the third terminal electrode,
The first connection means includes a first connection portion formed to cross the first coil conductor in a layer different from the first conductor layer,
The second connection means has a second connection portion formed to cross the second coil conductor in a layer different from the second conductor layer,
The common mode filter, wherein the third connection means includes a third connection portion formed to cross the third coil conductor in a layer different from the third conductor layer. The first conductor layer further includes a fourth lead conductor connected to the fourth terminal electrode,
The second conductor layer further includes a connection conductor for a first coil conductor that is formed in an inner region of the second coil conductor and connects the inner end of the first coil conductor and the fourth lead conductor;
The fourth lead conductor and the connection conductor for the first coil conductor constitute a part of the first connection means,
The common mode filter according to claim 1, wherein the first connection portion is a connection conductor for the first coil conductor. The first conductor layer further includes a fifth lead conductor connected to the fifth terminal electrode, and a sixth lead conductor connected to the sixth terminal electrode,
The fifth lead conductor constitutes a part of the second connecting means;
The sixth lead conductor constitutes a part of the third connecting means;
The second connecting portion is a part of the fifth lead conductor;
The common mode filter according to claim 2, wherein the third connection portion is a part of the sixth lead conductor. The first insulating layer includes two first contact holes connecting the inner end of the first coil conductor, the fourth lead conductor, and the connection conductor for the first coil conductor, and the second coil conductor. A second contact hole that connects the inner end and the fifth lead conductor; and a third contact hole that connects the inner end of the third coil conductor and the sixth lead conductor;
The second insulating layer has a fourth contact hole that connects an inner end of the third coil conductor and the sixth lead conductor,
Each of the first contact holes constitutes a part of the first connection means,
The second contact hole constitutes a part of the second connection means,
4. The common mode filter according to claim 3, wherein the third contact hole and the fourth contact hole constitute a part of the third connection means. The first conductor layer further includes a fifth lead conductor connected to the fifth terminal electrode,
The third conductor layer further includes a sixth lead conductor connected to the sixth terminal electrode;
The second conductor layer further includes a connection conductor for a third coil conductor that is formed in an inner region of the second coil conductor and connects the inner end of the third coil conductor and the sixth lead conductor,
The fifth lead conductor constitutes a part of the second connecting means;
The sixth lead conductor and the connection conductor for the third coil conductor constitute a part of the third connection means,
The second connecting portion is a part of the fifth lead conductor;
The common mode filter according to claim 2, wherein the third connection portion is a connection conductor for the third coil conductor. The first insulating layer includes two first contact holes connecting the inner end of the first coil conductor, the fourth lead conductor, and the connection conductor for the first coil conductor, and the second coil conductor. A second contact hole connecting an inner end and the fifth lead conductor;
The second insulating layer has two third contact holes that respectively connect an inner end of the third coil conductor and the sixth lead conductor and a connection conductor for the third coil conductor,
Each of the first contact holes constitutes a part of the first connection means,
The second contact hole constitutes a part of the second connection means,
6. The common mode filter according to claim 5, wherein each of the third contact holes constitutes a part of the third connecting means. The second conductor layer further includes a fifth lead conductor connected to the fifth terminal electrode,
The third conductor layer further includes a sixth lead conductor connected to the sixth terminal electrode;
The first conductor layer is formed in an outer region of the first coil conductor, and includes a connection conductor for a second coil conductor that connects an inner end of the second coil conductor and the fifth lead conductor, and the first conductor layer. A connection conductor for a third coil conductor that is formed in an outer region of the coil conductor and connects the inner end of the third coil conductor and the sixth lead conductor;
The fifth lead conductor and the connection conductor for the second coil conductor constitute a part of the second connection means,
The sixth lead conductor and the connection conductor for the third coil conductor constitute a part of the third connection means,
The second connection portion is a connection conductor for the second coil conductor,
The common mode filter according to claim 2, wherein the third connection portion is a connection conductor for the third coil conductor. The first insulating layer includes two first contact holes connecting the inner end of the first coil conductor, the fourth lead conductor, and the connection conductor for the first coil conductor, and the second coil conductor. Two second contact holes for connecting the inner end and the fifth lead conductor and the connection conductor for the second coil conductor, respectively, the inner end of the third coil conductor, the sixth lead conductor and the third coil Two third contact holes for connecting the conductor connection conductors, respectively,
The second insulating layer has two fourth contact holes for connecting the inner end of the third coil conductor and the sixth lead conductor and the connection conductor for the third coil conductor, respectively.
Each of the first contact holes constitutes a part of the first connection means,
Each of the second contact holes constitutes a part of the second connection means,
8. The common mode filter according to claim 7, wherein each of the third contact holes and each of the fourth contact holes constitutes a part of the third connection means.   The common mode filter according to claim 2, wherein a line length of at least one of the first coil conductor and the third coil conductor is shorter than a line length of the second coil conductor. .

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