JP2002203718A - Laminated common mode choke coil - Google Patents

Abstract

(57) [Summary] A magnetic coupling between two coils is small.
In order to increase the magnetic coupling between the two coils, a fine processing technology and a lamination technology for controlling and forming an extremely thin insulator were required. Also, increasing the number of turns increases the resistance value. SOLUTION: A first magnetic substrate, a laminated body in which an insulator layer formed on a surface of the first magnetic substrate by a thick film forming means and two coil patterns are stacked in a thickness direction, A second magnetic substrate sandwiching the laminate between the first magnetic substrate and the first magnetic substrate, and two coils are formed in the laminate. One extraction electrode of each of the two coils and a plurality of coil patterns electrically coupled to each of the two coil patterns are formed on the same insulator layer formed between the two coil patterns. . [Effect] It is possible to reduce resistance while maintaining excellent electrical characteristics.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated common mode choke coil for removing common mode noise in a differential transmission line or the like.

[0002]

2. Description of the Related Art There is a common mode choke coil of this type in which a pair of wires 53 and 54 are wound around a core 51 as shown in FIG. Since such a common mod choke coil is formed by winding a wire around a core, there is a limit to miniaturization. Therefore, in recent years, a solid-state laminated common mode choke coil that does not use a wire has been developed for miniaturization.

As shown in FIG. 6, a magnetic green sheet 61 on which a first coil pattern 63 is formed and a magnetic green sheet 62 on which a second coil pattern 64 is formed, as shown in FIG. Are laminated alternately and integrally fired, and an external electrode is formed on the side surface of the laminate. In this laminated common mode choke coil, the first coil pattern 63 between the magnetic layers is spirally connected, and the second coil pattern 64 between the magnetic layers is spirally connected, so that two coils are formed in the laminated body. It is formed.

As shown in FIG. 8, a plurality of insulator layers 82A, 82B, 82C, 82D and spiral coil patterns 83, 84 are provided on the surface of a magnetic substrate 81A, as shown in FIG. And the extraction electrode 83
A and 84A are stacked in the thickness direction, a magnetic substrate 81B is stacked on the laminated body of the insulator layer and the coil pattern, and the laminated body of the insulator layer and the coil pattern is sandwiched between the magnetic substrate 81A and the magnetic substrate 81B. There is something. The multilayer common mode choke coil is connected to an extraction electrode 8 connected to the inner end of the spiral coil pattern 83.
An extraction electrode 84A connected to 3A and the inner end of the spiral coil pattern 84 is formed on the insulator layer 82B formed between the spiral coil patterns 83 and 84.

[0005]

The conventional laminated common mode choke coil shown in FIG. 6 utilizes the green sheet laminating technology, and therefore has high productivity and can be made smaller than that of FIG. However, in this laminated common mode choke coil, since the entire periphery of the coil pattern is filled with a magnetic material, the flow of magnetic flux does not have an ideal distribution such as φ1 and φ2 as shown in FIG. Leakage flux is generated like φA and φB. Therefore, the conventional laminated common mode choke coil shown in FIG. 6 has a problem that the magnetic coupling between the two coils is small, and the characteristics of the common mode choke coil are deteriorated.

The conventional laminated common mode choke coil shown in FIG. 8 has a spiral coil pattern 83 and a spiral coil pattern 8 while ensuring insulation.
The magnetic coupling between the two coils can be increased as compared with that shown in FIG. 6, and a high impedance can be obtained by minimizing the interval between the four coils and increasing the number of turns of each spiral coil pattern. it can. However, in order to increase the magnetic coupling between the two coils and increase the impedance, the laminated common mode choke coil requires a fine processing technology for realizing a large number of turns in a limited space and an extremely thin type. A lamination technique for controlling and forming the insulator layer is required. In addition, since a large number of turns is required to obtain good characteristics, an increase in resistance is unavoidable, and there is a demand for reducing the resistance as much as possible in a differential transmission line using a common mode choke coil. I couldn't respond.

An object of the present invention is to provide a laminated common mode choke coil capable of lowering resistance while maintaining excellent electrical characteristics.

[0008]

The laminated common mode choke coil according to the present invention is electrically coupled to each of the two coil patterns on the same insulator layer formed between the two coil patterns. The above-mentioned problem is solved by forming a plurality of coil patterns.
That is, the first magnetic substrate and the insulator layer, the first coil pattern, and the second coil pattern formed by the thick film forming means on the surface of the first magnetic substrate are stacked in the thickness direction. And a second magnetic substrate sandwiching the laminate between the first magnetic substrate and the first magnetic substrate, wherein two coils are formed in a laminated common mode choke coil in which two coils are formed in the laminate. , A third coil pattern electrically coupled to the first coil pattern, and a fourth coil pattern electrically coupled to the second coil pattern, respectively, Second
Are formed on the same insulator layer formed between the coil patterns. Further, the present invention provides a first magnetic substrate, an insulator layer and a spiral first coil pattern formed on a surface of the first magnetic substrate by a thick film forming means, and a spiral first coil pattern. And a second magnetic substrate sandwiching the laminate between the first magnetic substrate and a second magnetic substrate, wherein two coils are formed in the laminate. Type common mode choke coil, each of the two coils has one extraction electrode,
A plurality of third coil patterns connected in parallel to the spiral first coil pattern; and a spiral second coil pattern.
A plurality of fourth coil patterns connected in parallel to the first coil pattern are formed on the same insulator layer formed between the first spiral coil pattern and the second spiral coil pattern. You.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A multilayer common mode choke coil according to the present invention comprises a pair of magnetic substrates and a laminate of an insulator layer and a conductor layer sandwiched between the pair of magnetic substrates. . The laminated body of the insulator layer and the conductor layer is formed on the surface of the magnetic substrate by using a thick film forming means, the insulator layer, the pair of spiral coil patterns, and the inner end of each spiral coil pattern. , And a plurality of coil patterns connected in parallel with the respective spiral coil patterns. At this time, the extraction electrode connected to the inner end of each spiral coil pattern and the plurality of coil patterns connected in parallel with each spiral coil pattern are formed between a pair of spiral coil patterns. Formed on the surface of the same insulator layer. As a result, the two coils face not only vertically but also horizontally.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a multilayer common mode choke coil according to the present invention will be described below with reference to FIGS. FIG. 1 is an exploded perspective view showing an embodiment of the multilayer common mode choke coil of the present invention, FIG. 2 is a perspective view showing an embodiment of the multilayer common mode choke coil of the present invention, and FIG. 3 is a sectional view of FIG. is there. 1, 2 and 3, 11A, 1
1B is a magnetic substrate, 12A to 12D are insulator layers, 13,
Reference numeral 14 denotes a spiral coil pattern. The magnetic substrates 11A and 11B are formed of a magnetic material such as ferrite,
The insulator layers 12A to 12D are formed of an insulating material other than a magnetic material. A spiral coil pattern 13 is formed on the surface of the insulator layer 12A formed on the surface of the magnetic substrate 11A. This spiral coil pattern 13
The outer end is drawn out to the end face of the insulator layer 12A. An insulator layer 12B is formed on the insulator layer 12A. On the surface of the insulator layer 12B, a lead electrode 13 connected to an inner end of the spiral coil pattern 13 is provided.
A, a plurality of coil patterns 15 connected in parallel to the spiral coil pattern 13, and a lead electrode 14 connected to an inner end of the spiral coil pattern described later.
A and a plurality of coil patterns 16 connected in parallel to a spiral coil pattern described later are formed. The extraction electrode 13A and the extraction electrode 14A have their respective ends extended so as not to be in contact with each other at the center of the insulator layer 12B. The extraction electrode 14A is formed such that one end thereof faces an inner end of a spiral coil pattern described later. In addition, in FIG.
One end of 4A is connected to one of the carp patterns 16. The other end of the extraction electrode 13A and the other end of the extraction electrode 14A are extracted to the same end surface of the insulator layer 12B. Also,
A plurality of coil patterns 15 and a plurality of coil patterns 16
Is formed at a position facing the spiral coil pattern 13 so that the coil patterns 15 and the coil patterns 16 are alternately arranged along the spiral coil pattern 13. At this time, the line width of the coil patterns 15 and 16 is formed to be equal to or wider than the line width of the spiral coil pattern 13. Both ends of the coil pattern 15 and both ends of the coil pattern 16 are connected to the extraction electrodes 13A,
It is formed so as not to contact 4A. Then, one end of the extraction electrode 13A is connected to the inner end of the spiral coil pattern 13 via a conductor in a through hole of the insulator layer 12B. The ends of the plurality of coil patterns 15 are sequentially connected to the spiral coil pattern 13 via conductors in through holes of the insulator layer 12B. On this insulator layer 12B, an insulator layer 12C
Is formed. A spiral coil pattern 14 is formed on the surface of the insulator layer 12C. The spiral coil pattern 14 includes a plurality of coil patterns 15
And at a position facing the plurality of coil patterns 16 so as to be in the same winding direction as the spiral direction of the spiral coil pattern 13. The inner end of the spiral coil pattern 14 is connected to one end of the extraction electrode 14A (the connection point between the extraction electrode 14A and the coil pattern 16 in FIG. 1) via a conductor in a through hole of the insulator layer 12C. The spiral coil pattern 14 is connected to the coil pattern 16 via conductors in through holes provided at positions corresponding to both ends of the coil pattern 16 of the insulator layer 12C. An insulator layer 12D is formed on the insulator layer 12C, and a magnetic substrate 11B is further laminated thereon.

As shown in FIG. 2, external electrodes 21, 22, 23 and 24 are formed on the opposing side surfaces of the element body in which these elements are integrated. Then, the spiral coil pattern 13
And the coil formed by the coil pattern 15 and the extraction electrode 13A are connected between the external electrode 21 and the external electrode 22. Further, a coil formed by the spiral coil pattern 14, the coil pattern 16, and the extraction electrode 14A is connected between the external electrode 23 and the external electrode 24.

The laminated common mode choke coil is manufactured as follows. First, a photosensitive conductive paste is applied to the entire surface of an insulator layer formed by a thick film forming means such as a printing method or a spin coating method on a pre-baked magnetic substrate, and the photosensitive conductive paste is applied by the thick film forming means and dried. Then, masking is performed so that a portion to be a spiral coil pattern remains, and exposure is performed using ultraviolet light or the like, portions other than the spiral coil pattern are removed by development, and these portions are baked, as shown in FIG. Then, a spiral coil pattern 43 is formed on the surface of the insulator layer 42A. A photosensitive insulator paste is applied to the entire surface of the insulator layer 42A on which the spiral coil pattern 43 is formed by a thick film forming means and dried, and then the position corresponding to the inner end of the spiral coil pattern 43 and the spiral shape are formed. Masking is performed such that portions other than the through-holes at positions corresponding to both ends of the coil pattern connected to the coil pattern 43 are exposed, and are exposed to ultraviolet light or the like, and portions that become the through-holes are removed by development. By sintering, as shown in FIG. 4 (B), through holes 47 are provided at positions corresponding to the inner ends of the spiral coil pattern and at positions corresponding to both ends of a coil pattern described later connected to the spiral coil pattern. An insulator layer 42B is formed. Next, a photosensitive conductive paste is applied to the entire surface of the thus-formed insulator layer by a thick-film forming means, dried, and then subjected to masking so that a portion serving as an extraction electrode and a coil pattern remains. Exposure to ultraviolet light, etc., and removal of portions other than the extraction electrode and the coil pattern by development and baking of
As shown in (C), the extraction electrode 43 is formed on the surface of the insulator layer 42B.
A, 44A and coil patterns 45, 46 are formed. The lead electrode 43A and the coil pattern 45 are filled with the photosensitive conductive paste in the through holes when the photosensitive conductive paste is applied to the entire surface of the insulator layer 42B,
Each is connected to the spiral coil pattern 43. Further, a photosensitive insulator paste is applied to the entire surface of the insulator layer 42B by a thick film forming means and dried, and then a position corresponding to an inner end of a spiral coil pattern described later and a spiral coil pattern described later are used. Masking is performed so that portions other than the through-holes at positions corresponding to both ends of the coil pattern to be connected are left and exposed with ultraviolet light or the like, and the portions that become the through-holes are removed by development, and these are fired. , FIG.
As shown in (D), an insulator layer 42C having a through hole 48 is formed at a position corresponding to an inner end of a spiral coil pattern described later and at a position corresponding to both ends of the coil pattern. Further, a photosensitive conductive paste is applied to the entire surface of the insulator layer thus formed by a thick film forming means, dried, and then subjected to masking so that a portion serving as a spiral coil pattern remains. Exposure to ultraviolet light or the like, development to remove portions other than the spiral coil pattern, and baking them,
As shown in (E), a spiral coil pattern 44 is formed on the surface of the insulator layer 42C. When applying the photosensitive conductive paste to the entire surface of the insulator layer 42C, the spiral coil pattern 44 is filled with the photosensitive conductive paste in the through holes and connected to the extraction electrode and the coil pattern. Further, after an insulator layer is formed on the insulator layer, a magnetic substrate fired in advance is laminated, adhered, and integrated. Then, a conductive paste is applied to a predetermined position of the element body in which these are integrated by printing or the like, and baked to form an external electrode.

[0013]

As described above, the multilayer common mode choke coil according to the present invention comprises the first magnetic substrate and the first magnetic substrate.
A laminate in which an insulator layer formed on the surface of the magnetic substrate by the thick film forming means, a first coil pattern, and a second coil pattern are stacked in the thickness direction; A second magnetic substrate sandwiching the laminate therebetween, a third electrode pattern electrically coupled to the first coil pattern, and one of the extraction electrodes of each of the two coils formed in the laminate. Since the fourth coil pattern electrically coupled to the second coil pattern is formed on the same insulator layer formed between the first coil pattern and the second coil pattern, , The magnetic coupling between the two coils can be increased as compared with the conventional one, and the resistance value can be reduced as compared with the conventional one. Therefore, the multilayer common mode choke coil of the present invention can reduce resistance while maintaining excellent electrical characteristics.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing an embodiment of a multilayer common mode choke coil of the present invention.

FIG. 2 is a perspective view showing an embodiment of the multilayer common mode choke coil of the present invention.

FIG. 3 is a sectional view of FIG. 2;

FIG. 4 is a plan view showing the steps of the multilayer common mode choke coil of the present invention.

FIG. 5 is a perspective view of a conventional common mode choke coil.

FIG. 6 is an exploded perspective view of a conventional laminated common mode choke coil.

FIG. 7 is a sectional view of FIG. 6;

FIG. 8 is an exploded perspective view of another conventional laminated common mode choke coil.

[Explanation of symbols]

 11A, 11B Magnetic substrate 12A-12D Insulator layer 13, 14 Spiral coil pattern

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01F 37/00 H01F 37/00 A

Claims (5)

[Claims] A first magnetic substrate; an insulating layer formed on a surface of the first magnetic substrate by a thick film forming means;
And a second magnetic substrate sandwiching the laminate between the first magnetic substrate and the first magnetic substrate, and a laminated body in which the coil pattern and the second coil pattern are stacked in the thickness direction. In a laminated common mode choke coil in which two coils are formed, one extraction electrode of each of the two coils and the first
A third coil pattern electrically coupled to the first coil pattern and a fourth coil pattern electrically coupled to the second coil pattern are formed by the first coil pattern and the second coil pattern.
Characterized by being formed on the same insulator layer formed between the coil patterns. 2. A third coil pattern electrically coupled to the first coil pattern and a fourth coil pattern electrically coupled to the second coil pattern are electrically connected to one of the coil patterns. 2. The multilayer common mode choke coil according to claim 1, wherein a coil pattern to be coupled and a coil pattern electrically coupled to the other coil pattern are formed so as to alternate with the extraction electrode as a boundary. 3. 3. A first magnetic substrate, an insulator layer formed on the surface of the first magnetic substrate by a thick film forming means, a spiral first coil pattern, and a spiral second coil.
A laminate in which the coil patterns are stacked in the thickness direction,
A second magnetic substrate sandwiching the laminated body between the first magnetic substrate and the first magnetic substrate, wherein a laminated common mode choke coil in which two coils are formed in the laminated body; A plurality of third coil patterns connected in parallel to the spiral first coil pattern, and a plurality of fourth coil patterns connected in parallel to the spiral second coil pattern. Characterized in that the coil pattern is formed on the same insulator layer formed between the spiral first coil pattern and the spiral second coil pattern. coil. 4. A first magnetic substrate, an insulator layer formed on a surface of the first magnetic substrate by a thick film forming means, a spiral first coil pattern, and a spiral second coil substrate.
A laminate in which the coil patterns are stacked in the thickness direction,
A second magnetic substrate sandwiching the laminate between the first magnetic substrate and a laminated common mode choke coil in which two coils are formed in the laminate; A lead electrode connected to the inner end of the first coil pattern; a lead electrode connected to the inner end of the spiral second coil pattern; and a parallel connection to the spiral first coil pattern The plurality of third coil patterns and the plurality of fourth coil patterns connected in parallel to the spiral second coil pattern are formed by the spiral first coil pattern and the spiral second coil pattern. A laminated common mode choke coil formed on the same insulator layer formed between two coil patterns. 5. The plurality of third coil patterns and the plurality of fourth coil patterns are formed in parallel with the first and second spiral coil patterns so as to alternate with each other. 5. The multilayer common mode choke coil according to claim 3 or claim 4.