JP2003069358A - Layered filter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a layered filter with high reliability and high characteristic stability. SOLUTION: A capacitor 22 is formed by electrodes 1A, 2A, 3A and dielectric layers 2, 3 and a dielectric layer 1 placed among them, and a capacitor 23 is formed by electrodes 10A, 11A, 12A and dielectric layers 11, 12 and a dielectric layer 10 placed among them. Dielectric layers 5 to 8 are sequentially layered between the capacitors 22 and 23 and a coil 21 is formed of conductor patterns 5A to 8A placed in the dielectric layers 5 to 8 and via-holes 6B to 8B placed to the dielectric layers 6 to 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multilayer filter having a small size and a high noise removing capability, which is used for removing noise from electronic devices and the like.

[0002]

2. Description of the Related Art In recent years, there has been an increasing demand for reduction in size and weight of electronic devices incorporating electronic parts.
The demand for small laminated electronic components has increased rapidly. Along with the large number of such electronic components arranged on a circuit board, a multilayer filter, which is a type of multilayer electronic component in which a coil and a capacitor are integrated, is used as a countermeasure for high frequency noise on the circuit board. Came to be.

As a conventional laminated filter of this type, for example, Japanese Patent Publication No. 6-93589 and Japanese Patent Laid-Open No. 2000-1.
A noise filter disclosed in Japanese Patent No. 82892 is known. As shown in FIG. 9 and FIG.
In Japanese Patent Laid-Open No. 93589/1999, an inductor layer 104 formed by a conductor line 113 is provided inside a magnetic layer 101, and two or more internal electrodes 105 to 108 are provided inside to form dielectric layers 102 and 103 as capacitors. , The upper and lower parts of the magnetic layer 101 are laminated respectively, and these capacitors and the inductor layer 104 are provided with the external electrodes 110, 111.
A noise filter having a structure connected by is disclosed.

Further, in Japanese Unexamined Patent Publication No. 2000-182892, a capacitor block 213 as shown in FIG. 12 formed by alternately laminating dielectric ceramics 211 and internal electrodes 212 shown in FIG. A noise filter having a coil block 214 in which a non-magnetic glass layer 215 and an internal electrode 216 are alternately laminated, and a structure in which the capacitor block 213 and the coil block 214 are connected by an external electrode (not shown) is disclosed. There is.

[0005]

However, the Japanese Patent Publication No. 6-9
In the first prior art disclosed in Japanese Patent No. 3589, the magnetic layer 1
01 and the dielectric layers 102 and 103 are laminated and simultaneously fired to form a noise filter, so that stress due to a difference in thermal contraction is likely to occur at the boundary surface between the magnetic layer 101 and the dielectric layers 102 and 103. , Distortion, cracks, characteristic changes, etc.
It has the drawback of poor reliability.

In the second conventional technique disclosed in Japanese Patent Laid-Open No. 2000-182892, the dielectric ceramics 211 is used.
The capacitor block 213 serving as a capacitor is manufactured by baking the laminated structure of the internal electrode 212 and the internal electrode 212, and the non-magnetic glass layer 215 and the internal electrode 216 are stacked on the upper surface of the capacitor block 213 and baked to form the coil block 214. I am making it.

Therefore, the coil block 214, which constitutes the upper part of the noise filter, has a structure like an air-core coil whose characteristics fluctuate greatly when a metal or the like that obstructs the magnetic flux is present outside. If it is arranged close to the shield material, the characteristics fluctuate, and for example, there is a drawback that the noise removal characteristics in a high frequency region cannot be sufficiently obtained. The present invention has been made in consideration of the above facts, and an object thereof is to provide a laminated filter having high reliability and high characteristic stability.

[0008]

A multilayer filter according to a first aspect of the present invention comprises a coil formed by arranging a conductor pattern on a non-magnetic insulating layer and an electrode arranged in a dielectric layer. And a pair of capacitors respectively positioned with the coil interposed therebetween.

The operation of the laminated filter according to claim 1 will be described below. In the multilayer filter according to the present invention, a coil is formed by arranging a conductor pattern on a non-magnetic insulating layer, and a pair of capacitors respectively formed by electrodes arranged in the dielectric layer is a coil. They are located on both sides of.

Therefore, according to the present invention, since the non-magnetic insulating layer different from the magnetic material such as ferrite is adopted and the coil is constituted by the conductor pattern arranged in the non-magnetic insulating layer, The coil has a structure similar to that of an air-core coil. However, by arranging a pair of capacitors sandwiching this coil, it is possible not only to ensure the distance between the coil and the external metal, etc. by these pairs of capacitors, but also due to the presence of electrodes inside the capacitor. ,
It is possible to eliminate the influence of external metal etc. on the magnetic flux of the coil, and the characteristics of the coil are stabilized.

Further, unlike the magnetic layer, a non-magnetic insulating layer having a composition close to that of the dielectric layer is laminated with the dielectric layer, so that even when these layers are simultaneously fired to form a laminated filter, Stress due to the difference in thermal contraction is unlikely to occur at the boundary surface between the non-magnetic insulator layer and the dielectric layer, and the reliability is not deteriorated due to distortion, cracking, characteristic fluctuation, and the like. From the above results, according to the present invention, it is possible to obtain a small multilayer filter that surely has a high noise removal characteristic even in a high frequency region.

The operation of the laminated filter according to the second aspect will be described below. The present invention has the same structure as that of claim 1 and operates in the same manner, but further, the relative dielectric constant of the nonmagnetic insulating layer in which the coil is arranged is 10 or less, and the dielectric layer forming the capacitor. Has a relative dielectric constant of 20 to 200. That is, from the viewpoint of ensuring the electromagnetic characteristics required for the coil, it is not necessary to increase the relative permittivity, so that the relative permittivity of the non-magnetic insulating layer on which the coil is arranged is set to 10 or less as described above. Will be enough.

Further, in consideration of the characteristic deterioration due to the capacitance generated between the input and output terminals, it is preferable that the dielectric constant of the dielectric layer forming the capacitor is 200 or less, and the minimum required for the capacitor. From the viewpoint of ensuring the capacitance value, it is preferable that the dielectric constant of the dielectric layer forming the capacitor is 20 or more.

The operation of the laminated filter according to claim 3 will be described below. The present claim has the same configuration as that of claim 1 and operates in the same manner, but further, the relative permittivity of the non-magnetic insulating layer in which the coil is arranged and the relative permittivity of the dielectric layer forming the capacitor. The rate is the same as each other. That is, if the relative permittivity of the non-magnetic insulator layer and the relative permittivity of the dielectric layer are made to be the same as each other, the non-magnetic insulator layer and the dielectric layer are made of, for example, a material having the same composition. Therefore, it is possible to easily manufacture the multilayer filter, and it is possible to obtain the multilayer filter at low cost and with high reliability and characteristic stability.

A multilayer filter according to a fourth aspect of the present invention includes a coil formed by arranging a conductor pattern on a first dielectric layer and an electrode arranged in a second dielectric layer, and It has a pair of capacitors respectively located on both sides of the coil.

The operation of the laminated filter according to claim 4 will be described below. The laminated filter according to the present invention is the first
A coil is formed by arranging a conductor pattern on the dielectric layer, and a pair of capacitors each formed by the electrodes arranged in the second dielectric layer are located with the coil in between.

Therefore, according to the present invention, the dielectric layer different from the magnetic material such as ferrite is adopted, and the coil is constituted by the conductor pattern arranged on the dielectric layer. The structure is similar to that of an air-core coil. However, by arranging the pair of capacitors with the coil sandwiched therebetween, it is possible to eliminate the influence of the external metal or the like on the magnetic flux of the coil, and the characteristics of the coil are stabilized.

Further, with the use of the dielectric layer as the insulating material for the coil, the three dielectric layers are laminated, so that the stress due to the difference in thermal contraction is generated at the interface between them. And reliability is further enhanced. From the above results, according to the present invention, as in the first aspect, it is possible to obtain a small-sized multilayer filter that surely has high noise removal characteristics even in a high frequency region.

The operation of the laminated filter according to the fifth aspect will be described below. The present claim has the same structure as that of claim 4 and operates in the same manner, but further comprises a first coil in which a coil is arranged.
The dielectric layer has a relative permittivity of 10 or less, and the second dielectric layer forming the capacitor has a relative permittivity of 20 to 200. That is, from the viewpoint of ensuring the electromagnetic characteristics required for the coil, there is no need to increase the relative permittivity, so the relative permittivity of the first dielectric layer in which the coil is arranged is set to 10 or less as described above. Will be enough.

Further, considering the characteristic deterioration due to the capacitance generated between the input and output terminals, it is preferable that the relative dielectric constant of the second dielectric layer forming the capacitor is 200 or less as described above, and it is necessary for the capacitor. From the viewpoint of ensuring the minimum capacitance value, it is preferable that the relative dielectric constant of the second dielectric layer forming the capacitor is 20 or more.

The operation of the laminated filter according to claim 6 will be described below. The present claim has the same structure as that of claim 4 and operates in the same manner, but further comprises a first coil in which a coil is arranged.
The dielectric constant of the dielectric layer and the dielectric constant of the second dielectric layer forming the capacitor are the same. That is, since the portion where these coils are arranged and the portion where the capacitor is formed are made of a dielectric layer having the same composition, the manufacture of the multilayer filter is facilitated, and the reliability is low and the cost is the same as in claim 3. It is possible to obtain a laminated filter having high stability and stability of characteristics.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION A laminated noise filter 4 which is a first embodiment of a laminated filter according to the present invention will be described below.
The present invention will be clarified by explaining 0 with reference to the drawings. As shown in FIG. 1 to FIG. 3, the laminated noise filter 40 according to the present embodiment is composed of 13 dielectric layers 1 to 13 each made of a ceramic or the like and formed in a rectangular shape in a sheet shape. A main body laminated portion 40A, which is laminated to form a rectangular parallelepiped structure, is a main portion.

As shown in FIG. 1, the dielectric layers 1 to 3 formed by laminating the lower portion of the laminated noise filter 40.
The electrodes 1 are formed in a rectangular shape by printing or the like.
A to 3A are respectively arranged in order from the bottom, and the dielectric layers 10 to 12, which are also formed by stacking the upper portion of the multilayer noise filter 40, are similarly formed into rectangular electrodes 10A. 12A are arranged in order from the bottom. Then, the electrodes 1A, 2A, 3A and the dielectric layers 2, 3 located between them and the dielectric layer 1
Form a capacitor 22 with electrodes 10A, 11
A, 12A and the dielectric layer 11 located between them,
The capacitor 23 is formed by 12 and the dielectric layer 10.

Further, electrodes 1A, 3A, 10A, 12A
1 has a pair of lead-out portions 20 protruding from the lower right side and the upper left side in FIG.
A, 3A, 10A, and 12A, respectively.
Further, the back side portions of the electrodes 2A and 10A in FIG. 1 extend to the end portions of the dielectric layers 2 and 10, respectively.

On the other hand, between the capacitors 22 and 23, dielectric layers 5 to 8 which are non-magnetic insulating layers and serve as a first dielectric layer are sequentially laminated. On the dielectric layer 5, a conductor pattern 5A is formed, which is wound in a substantially C shape on the dielectric layer 5 and extends the connection portion 15 which is one end to the end portion on the back side of the dielectric layer 5. It is arranged.

The dielectric layer 6 is provided with a conductor pattern 6A wound around the dielectric layer 6 in a substantially C-shape, and the dielectric layer 7 is covered with a conductor pattern 6A. A conductor pattern 7A wound in a substantially C shape is arranged. Further, the conductor pattern 8A is formed by winding the dielectric layer 8 in a substantially C shape on the dielectric layer 8 and extending the connecting portion 18 which is one end to the front end of the dielectric layer 8. But,
It is arranged. The conductor patterns 5A to 5B are formed by the via holes 6B to 8B penetrating the dielectric layers 6 to 8, respectively.
8A end portions are connected to each other, and these conductor patterns 5A
The coil 21 is completed by continuing ~ 8A.

From the above, the conductor patterns 5A to 8A arranged so as to surround the dielectric layers 5 to 8 and the dielectric layer 6 are formed.
The coil 21 is formed by the via holes 6B to 8B disposed in the dielectric layers 5 to 8 and the laminated layer sandwiching the dielectric layers 5 to 8 in which the coil 21 exists from above and below serves as the second dielectric layer. 1-3, 10-12, and these dielectric layers 1-3, 10-12 and electrodes 1A-3A, 10A-.
The capacitors 22 and 23 are formed by 12A.

A dielectric layer 4 for adjusting the distance between the electrode 3A of the capacitor 22 and the conductor pattern 5A of the coil 21 is laminated between the dielectric layer 3 and the dielectric layer 5 described above. The conductor pattern 8A of the coil 21 and the capacitor 23 are provided between the dielectric layer 8 and the dielectric layer 10 described above.
Dielectric layer 9 for adjusting the distance between the electrode 10A and
Are stacked. A dielectric layer 13 serving as a base layer for protecting the electrode 12A of the capacitor 23 is laminated on the dielectric layer 12.

Then, the connecting portion 18 of the conductor pattern 8A, which is on one end side of the coil 21, is connected to the laminated noise filter 4.
0 of the main body laminated portion 40A is connected to the external electrode 31 arranged on the front end surface 40B. Capacitor 2
The end portion of the electrode 2A serving as the terminal portion of 2, the end portion of the electrode 10A serving as the terminal portion of the capacitor 23, and the connecting portion 15 of the conductor pattern 5A serving as the other end side of the coil 21 are also formed in the main body laminated portion 40A. It is connected by the external electrode 32 arranged on the end surface 40B on the back side.

That is, as shown in FIG. 3, the main body laminated portion 40A of the laminated noise filter 40 formed in a rectangular parallelepiped shape.
The external electrode 31 serving as an input terminal is arranged on the front end face 40B of the same, and the external electrode 32 serving as an output terminal is arranged on the rear end face 40B of the main body stacking portion 40A.

Similarly, both side surfaces 4 of the main body laminated portion 40A are
There are two external electrodes 33 and 34, which are ground terminals at 0C,
They are arranged while being connected to the lead-out portions 20 projecting to the corresponding portions. As a result of the above, the capacitor 2 of the multilayer noise filter 40 according to the present embodiment
Electrodes 2A and 11A of electrodes 1A to 3A and 10A to 12A constituting electrodes 2 and 23 are electrodes for signals, and electrodes 1A, 3A, and 10 having lead portions 20 respectively.
A and 12A will be electrodes for grounding.

From the above, the equivalent circuit of the laminated noise filter 40 according to the present embodiment is as shown in FIG. The inductance value of the coil 21 and the capacitance values of the capacitors 22 and 23 of the multilayer noise filter 40 can be adjusted by changing the width of the conductor pattern and the number of layers, but the capacitors 22 and 23 are made of materials having different relative dielectric constants. It is also possible to adjust by using as a dielectric layer.

In this embodiment, the coil 21
The relative dielectric constants of the dielectric layers 5 to 8 in which are arranged are 10 or less, and the relative dielectric constants of the dielectric layers 1 to 3 forming the capacitor 22 and the dielectric layers 10 to 12 forming the capacitor 23 are 20 to. For example, it may be set to 200. However,
The relative permittivity of the dielectric layers 5 to 8 and the dielectric layers 1 to 3 and 10
It is also conceivable that the relative dielectric constants of 12 are the same as each other.

Next, the manufacture of the laminated noise filter 40 according to this embodiment will be described. When manufacturing the laminated noise filter 40, a dielectric green sheet containing alumina and glass is formed in a sheet shape in which a plurality of dielectric layers 1 to 13 shown in FIG. Try to stack these.

At this time, the electrodes 1A to 3A and the conductor pattern 5
For A to 8A and electrodes 10A to 12A, a conductive paste such as silver or silver-palladium is printed on the dielectric layer, and the via hole 6 is formed.
B to 8B are formed by similarly filling a conductor paste in the dielectric layer. Furthermore, these dielectric layers 1-1
After laminating the dielectric green sheets to be No. 3 and cutting into chips and firing, the external electrodes 31 to 34 are installed by plating or the like to complete the laminated noise filter 40 shown in FIGS. 2 and 3. To be done.

Next, the operation of the laminated noise filter 40 according to this embodiment will be described below. In the laminated noise filter 40 according to the present embodiment, the conductor patterns 5A to 8A and the via holes 6B to 8B are arranged on the dielectric layers 5 to 8 which are nonmagnetic insulator layers, and these are laminated to form the coil 21. Is formed. Further, in the dielectric layers 1 to 3 and 10 to 12 which are laminated portions different from the dielectric layers 5 to 8,
A pair of capacitors 22 and 23 are formed by electrodes 1A to 3A and 10A to 12A, which are arranged to face each other with the dielectric layers 2, 3, 11, and 12 interposed therebetween, and these capacitors 22 and 23 are sandwiched with the coil 21 interposed therebetween. A pair of capacitors 2
2 and 23 are arranged respectively. Also, the dielectric layer 1
The external electrodes 31 to 34 are arranged outside the main body laminated portion 40A formed by laminating the coils 1 to 13, and the external electrodes 32 in the external electrodes 31 to 34 form the coil 2
1 and capacitors 22 and 23 are connected.

As described above, according to the present embodiment, the non-magnetic dielectric layers 5 to 8 different from the magnetic material such as ferrite are adopted, and the coil 21 is formed by the conductor pattern arranged on the dielectric layers 5 to 8. The coil 21 has a structure similar to that of an air-core coil. However, by arranging a pair of capacitors 22 and 23 sandwiching this coil 21 along the stacking direction of the dielectric layers (direction shown by arrow Z in FIG. 2), the magnetic flux of the coil 21 due to an external metal or the like. Can be eliminated, and the characteristics of the coil 21 are stabilized.

That is, when the multilayer noise filter 40 is mounted on a circuit board and incorporated into an electronic device, a metal shield material is placed close to the multilayer noise filter 40 as the electronic device becomes smaller. Were often placed in recent years. However, the laminated noise filter 40 according to the present embodiment has a sandwich structure in which the coil 21 is sandwiched between the pair of capacitors 22 and 23 along the laminating direction of the dielectric layers as described above.

Therefore, the presence of these capacitors 22 and 23 prevents the shield material from approaching the coil 21 more than necessary, so that not only can the distance between the coil 21 and the external metal be ensured. , Capacitor 2
Due to the presence of the metal parts of the electrodes 1A to 3A, 10A to 12A, etc. in 2, 23, the magnetic flux of the coil 21 does not change, and the characteristics of the coil 21 are always stabilized regardless of the presence or absence of the shield material. became.

Further, in this embodiment, the dielectric layers 1 to
3, 10 to 12 and the dielectric layers 5 to 8 made of a material different from that of the magnetic layer are the dielectric layers 1 to 10
~ 12 are stacked. Therefore, even when these are simultaneously fired to form the laminated noise filter 40, stress due to the difference in thermal contraction occurs at the boundary surface between the dielectric layers 5 to 8 and the dielectric layers 1 to 3 and 10 to 12. It is difficult, and the reliability will not deteriorate due to distortion, cracks, characteristic fluctuations, etc. From the above results, according to the present embodiment, it is possible to obtain the small multilayer noise filter 40 that surely has high noise removal characteristics even in the high frequency region.

On the other hand, in the present embodiment, the dielectric layer 5
The dielectric constants of 1 to 8 are 10 or less, and the dielectric layers 1 to 10
When the relative permittivity of ~ 12 is set to 20 to 200, the following operational effects are produced. That is, from the viewpoint of securing the electromagnetic characteristics required for the coil 21, it is not necessary to increase the relative permittivity in particular, so that the relative permittivity of the dielectric layers 5 to 8 on which the coil 21 is arranged is set to 10 above. The following is sufficient.

Further, considering the characteristic deterioration due to the capacitance generated between the input terminal and the output terminal, the dielectric layers 1 to 3, 10 to 12 forming the capacitors 22 and 23 are considered.
The relative dielectric constant of is preferably 200 or less,
Further, from the viewpoint of ensuring the minimum capacitance value necessary for the capacitors 22 and 23,
It is preferable that the dielectric constants of the dielectric layers 1 to 3 and 10 to 12 which form 3 are 20 or more.

On the other hand, in the present embodiment, the coil 21
And the portions forming the capacitors 22 and 23 are made into a dielectric layer having the same composition, the dielectric constants of the dielectric layers 5 to 8 in which the coil 21 is arranged are , The dielectric layers 1 to 3 forming the capacitors 22 and 23,
The relative permittivities of 10 to 12 can be the same as each other. As a result of making the relative permittivities the same, the laminated noise filter 40 is composed of only a single dielectric material, so that the laminated noise filter 40 can be easily manufactured at low cost. It is possible to obtain the laminated noise filter 40 having high reliability and stable characteristics.

On the other hand, the coil 21 and the capacitors 22 and 23
Between the main body laminated portion 40A of the laminated noise filter 40
Since the connection is made by the external electrode 32 disposed outside the inner side of the laminated type, the inside of the laminated noise filter 40 can be effectively used, and the use of the conductive material penetrating the dielectric layer such as the via hole is reduced. The laminated noise filter 40 can be manufactured at a lower cost.

Next, the second embodiment of the laminated filter according to the present invention
The embodiment will be described with reference to FIGS. 5 and 6. The same members as those described in the first embodiment are designated by the same reference numerals, and the duplicate description will be omitted. 5 and 6
The laminated noise filter 40 according to the present embodiment shown in FIG.
Has a structure similar to that of the first embodiment.
However, in the first embodiment, the back side portion of the electrode 10A in FIG. 1 extends to the end of the dielectric layer 10, whereas in the present embodiment shown in FIG. Instead of the side portion extending to the rear end portion of the dielectric layer 10, the front portion of the electrode 10A in FIG. 5 extends to the front end portion of the dielectric layer 10.

As a result, as shown in FIG. 5, in the present embodiment, the external electrode 31 (shown in FIG. 3) serving as an input terminal is connected to the connecting portion 18 of the electrode 10A and the conductor pattern 8A, and the output terminal In this structure, the external electrode 32 (shown in FIG. 3) that becomes the electrode 2A and the connecting portion 15 of the conductor pattern 5A is connected. That is, according to the present embodiment, unlike the first embodiment, the pair of capacitors 22 and 23 is different from that of FIG.
Thus, the laminated noise filter 40 that is separately present in the equivalent circuit diagram shown in FIG. At this time, the capacitor 24 shown by the dotted line in FIG. 6 which is the inter-terminal capacitance is present between the external electrode 31 and the external electrode 32.

From the above results, although the capacitors 22 and 23 are arranged individually in the equivalent circuit diagram of FIG. 6, the characteristics of the coil 21 are the same in the present embodiment as in the first embodiment. Is always stabilized regardless of the presence or absence of a metallic shield material, the reliability is not deteriorated due to characteristic fluctuations, etc., and the small multilayer noise filter 40 that surely has high noise removal characteristics even in a high frequency region.
Has come to be obtained.

Next, the attenuation characteristic data of the laminated noise filter 40 according to the present embodiment will be described in comparison with the attenuation characteristic data of the conventional noise filter. First, as a sample, the dimensions of height and width are 2.0 × 1.25 × 1.
A conventional noise filter having a small size of 0 mm or less and a laminated noise filter 40 according to the present embodiment having the same size are used.

The sample of this prior art noise filter corresponds to the second prior art shown in FIGS. 11 and 12, in which a coil is formed in a non-magnetic material and only one side of this coil is a capacitor. The multilayer noise filter 40 according to the present embodiment has a structure in which capacitors are arranged on both sides of a coil formed in a non-magnetic material. It

In FIG. 8, which shows the attenuation characteristic data of the noise filter of the prior art, the metal shield is shown from the attenuation characteristic (shown by the solid line in FIG. 8) when the metal shield material is not present in close proximity. The attenuation characteristics (indicated by the dotted line in FIG. 8) when the materials are close to each other are significantly deteriorated.

On the other hand, in FIG. 7 showing the attenuation characteristic data of the laminated noise filter 40 according to the present embodiment, the maximum attenuation amount of about 45 dB can be realized and the attenuation amount of 30 dB or more in a wide frequency range. In addition to the above, the attenuation characteristics when the metal shield material is present in close proximity and the attenuation characteristics when the metal shield material is not present in close proximity are the same and overlap (see FIG. 7). It shows with a solid line). That is, from the graph shown in FIG.
It was found that the attenuation characteristics did not deteriorate at all even when the metallic shield material was present close to each other, and the effect of the laminated noise filter 40 of the present embodiment that the characteristics were stable could be confirmed.

In the above embodiment, the present invention has been described using the small-sized laminated noise filter having the dimensions of 2.0 × 1.25 × 1.0 mm or less as described above. The present invention may be applied to a multilayer noise filter having a size exceeding the limit. Further, in the above embodiment, the non-magnetic insulator is a dielectric such as ceramic, but other known materials may be adopted.

[0053]

According to the laminated filter of the present invention, the excellent effect that the reliability and characteristic stability can be enhanced can be obtained.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing a laminated structure of a laminated noise filter according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a laminated noise filter according to the first embodiment of the invention.

FIG. 3 is a perspective view showing a laminated noise filter according to the first embodiment of the present invention.

FIG. 4 is an equivalent circuit diagram of the multilayer noise filter according to the first embodiment of the present invention.

FIG. 5 is an exploded perspective view showing a laminated structure of a laminated noise filter according to a second embodiment of the present invention.

FIG. 6 is an equivalent circuit diagram of a laminated noise filter according to a second embodiment of the present invention.

FIG. 7 is a diagram showing a graph showing attenuation characteristics of the laminated noise filter according to the exemplary embodiment of the present invention.

FIG. 8 is a diagram showing a graph showing attenuation characteristics of a noise filter according to a conventional technique.

FIG. 9 is a perspective view showing an internal conductor line and internal electrodes as seen through the main body of the noise filter according to the first conventional technique.

FIG. 10 is a perspective view showing a finished product of the noise filter according to the first conventional technique.

FIG. 11 is an exploded perspective view showing an internal structure of a capacitor block forming a noise filter according to a second conventional technique.

FIG. 12 is an exploded perspective view showing an internal structure of a noise filter according to a second conventional technique.

[Explanation of symbols]

1 to 13 dielectric layer 1A-3A electrode 5A-8A conductor pattern 10A to 12A electrode 21 coils 22 Capacitor 23 Capacitor 40 Stacked Noise Filter 40A main body laminated section

Claims (6)

[Claims] 1. A pair of coils, each of which is formed by arranging a conductor pattern on a non-magnetic insulating layer and an electrode arranged in a dielectric layer, and which is located with the coil sandwiched therebetween. A multilayer filter comprising: a capacitor. 2. The non-magnetic insulating layer in which the coil is arranged has a relative permittivity of 10 or less, and the dielectric layer forming the capacitor has a relative permittivity of 20 to 200. The laminated filter described. 3. The dielectric constant of the non-magnetic insulating layer in which the coil is arranged and the dielectric constant of the dielectric layer forming the capacitor are the same. Multilayer filter. 4. A coil formed by arranging a conductor pattern on a first dielectric layer, and an electrode arranged in a second dielectric layer, and the coils are positioned with the coil sandwiched therebetween. A multilayer filter comprising: a pair of capacitors that: 5. The dielectric constant of the first dielectric layer in which the coil is arranged is 10 or less, and the dielectric constant of the second dielectric layer forming the capacitor is 20 to 200. The multilayer filter according to claim 4. 6. The relative dielectric constant of the first dielectric layer in which the coil is arranged and the relative dielectric constant of the second dielectric layer forming the capacitor are the same as each other. Item 4
The laminated filter described.