JP2007027444A - Laminated common-mode choke coil and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laminated common-mode choke coil which is protected against a lamination failure in a coil pattern capable of displaying good impedance characteristics, even if the coil pattern is limited in number of lamination, reduced in size, and improved in productivity. <P>SOLUTION: A spiral conductor pattern 1 is formed on each of the prescribed layers. The conductor patterns 1 formed on the prescribed layers are optionally connected together through vias 2 jumping over the vertically adjacent conductor pattern layers, and formed into two coil patterns which are configured to be engaged with each other and electrically complementarily operated. In a laminate, the center and outer part of the spiral conductor pattern 1 are formed of a magnetic material 3, and the uppermost and lowermost layer are also formed of the magnetic material 3. On each layer, the conductor pattern 1 is located in the film layer region of a non-magnetic material 4, and arranged so as not to bring its edge into contact with the magnetic material 3. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a laminated common mode choke coil and a manufacturing method thereof. More specifically, the present invention relates to a laminated structure in which two coils are built in a laminated body, and a nonmagnetic material and a magnetic material portion corresponding to the coil pattern. It relates to the improvement of the arrangement relation.

  As is well known, a differential transmission system is widely used for data transmission in digital electronic devices such as personal computers. This differential transmission method is a method of transmitting two types of signals having opposite phases to a pair of transmission lines at a time, and has an advantage of being resistant to external noise and generating less noise and suitable for high-speed data transmission. The differential transmission method is used for many high-speed digital communications such as IEEE 394, LVDS.

  However, the differential transmission method has a problem that a common-mode component (common mode) is generated due to a slight difference in transmission characteristics between a pair of transmission lines, resulting in a noise current. Therefore, a common mode choke coil is used to effectively remove common mode noise.

  The common mode choke coil consists of two coils with the same number of turns. For the normal differential signal (normal mode), the magnetic flux generated in the two coils cancels each other and passes the signal as it is. In this case, the magnetic fluxes generated in the two coils are strengthened to generate a large impedance, and therefore, the operation for removing the common mode noise is performed.

  As this common mode choke coil, there is a winding type in which a wire is wound around a core, but as seen in Patent Document 1, for example, there is a laminated type in which a coil is built in a laminated body. This stacked type is preferred because it can be reduced in size compared to the wound type.

As shown in FIG. 1, the common mode choke coil is formed by forming the conductor pattern 1 constituting the coil in the region of the non-magnetic material 4, and the central portion, the outer portion, and the upper and lower portions of the two coils A and B. The outermost layer is formed from the magnetic body 3. These magnetic bodies 3 serve as a central yoke and an outer yoke, respectively.
Japanese Patent No. 2949244

  However, the conventional laminated common mode choke coil described above has the following problems. That is, in the laminated type, as shown in FIG. 1, the conductor pattern 1 serving as a coil is disposed close to the magnetic body 3 at the center, so that when the conductor pattern 1 is printed, There is a problem of bleeding from the boundary portion with the central magnetic body 3 to the lower layer side. For this reason, some of the upper and lower layers cause a defect that the conductor pattern 1 is short-circuited, resulting in a decrease in yield.

  In addition, the laminated type has a problem in that the coupling between the coils is worse than that of the wound type, and the common mode impedance at a high frequency is lowered. Therefore, when the number of turns is increased and the common mode impedance is increased, the number of stacked layers is significantly increased, resulting in an increase in the outer size. This is a problem that conflicts with the development requirements for electronic components. In other words, electronic devices such as portable personal computers are highly demanded of miniaturization and high speed. Therefore, even electronic components such as noise countermeasure components used in such devices need to be miniaturized and speeded up accordingly. Therefore, there is a demand for miniaturization of laminated common mode choke coils as much as possible.

  Furthermore, in the laminated type, the upper and lower magnetic layers are obtained by repeating the process of printing and drying the magnetic paste to obtain a predetermined thickness. It takes time and takes up a lot of time from the whole manufacturing process, so it cannot be said that productivity is good.

  Also, in the stacked type, since each layer is stacked from the lower layer side, the distortion on each layer surface accumulates sequentially, which causes cracks after the uppermost magnetic layer is formed and causes defects. .

  The present invention solves the above-mentioned problems, and its purpose is to prevent defects in the lamination of coil patterns and to obtain good impedance characteristics even if the number of laminations is limited to a small size. It is an object of the present invention to provide a laminated common mode choke coil that can be performed and has good productivity, and a method for manufacturing the same.

  In order to achieve the above-described object, the laminated common mode choke coil according to the present invention is formed by laminating an insulating film and a conductor pattern in an appropriate order, and by providing a via between the film layers and appropriately connecting the conductor pattern. In the laminated common mode choke coil in which two coils are built in the laminated body and the two coils are configured to be electrically complementary, the conductor pattern has a spiral shape, and the laminated body has a spiral shape center of the conductor pattern. The outer and upper outer layers are made of magnetic material, and the central and outer yokes for the two coils are used as the magnetic material. In each layer, the conductor pattern is located in the film layer region of the non-magnetic material, and the pattern edge The part is not in contact with the magnetic body.

  In addition, the spiral conductor pattern of each layer jumps over and connects adjacent conductor pattern layers, and the two coil patterns are alternately meshed with each other, and the magnetic substance in the center has a number of turns of the conductor pattern. It may be formed by enlarging the area of a small number of applicable layers and adjacent layers.

In the present invention, the insulating film and the conductor pattern are laminated in an appropriate order, vias are provided between the film layers, the conductor pattern is appropriately connected, and two coils are built in the laminated body. Is a method of manufacturing a laminated common mode choke coil configured to electrically complement operation,
The conductor pattern has a spiral shape, and the laminated body is formed of a magnetic material at the center and outer side of the spiral shape of the conductor pattern. In each layer, the conductor pattern is located in the film layer region of the nonmagnetic material and the pattern edge is Arranged so as not to contact the magnetic material, the conductor pattern, the non-magnetic material part and the magnetic material part are formed by the printing lamination method, and the upper and lower surfaces are formed by pressing the magnetic material sheet by the sheet forming method to form a film layer of a predetermined thickness. Alternatively, the upper and lower surfaces may be formed by pressing a single sheet of magnetic material having a predetermined thickness by a sheet forming method.

  Therefore, in the present invention, the laminated body has a magnetic part at the center and the outer part, and in each layer, the conductor pattern is located in the film layer region of the non-magnetic material and the pattern edge is not in contact with the magnetic substance. In pattern printing, silver paste can be prevented from flowing into the lower layer side.

  Further, since the conductor pattern of each layer is a spiral coil pattern, the number of winding turns per layer can be increased. Therefore, high inductance can be obtained while keeping the number of stacked layers small.

  The spiral conductor patterns of each layer are not connected in the order of stacking, but are connected by jumping over the adjacent conductor pattern layers on the upper and lower sides, and the two coil patterns are stacked in an alternately meshing state. The bond between is better.

  In addition, since the magnetic material in the central part is formed by expanding the area of the corresponding layer and the adjacent layer with a small number of winding turns of the conductor pattern, the magnetic material region approaches the pattern edge of the layer, thereby Coil coupling can be improved satisfactorily and the inductance value can be increased.

  Here, the film layer on which the conductor pattern is provided is formed by a printing lamination method, but the upper and lower surfaces are pressure-bonded with a plurality of magnetic sheets by a sheet forming method. Therefore, in order to form the upper and lower surface film layers, printing and drying processes are performed several times or several tens of times in the printing lamination method, but in the present invention, it is not necessary to perform such processes. Therefore, it is easy to form the upper and lower surfaces, which conventionally took a lot of time from the whole manufacturing process, and the working efficiency is greatly improved. In the present invention, since the printing and drying steps are not performed, the generation of cracks is eliminated.

  Even when a plurality of magnetic sheets are stacked and pressure-bonded to obtain a predetermined thickness, the working efficiency is better than that of the printing lamination method. Alternatively, a single magnetic sheet having a predetermined thickness may be prepared, and this may be configured to be crimped, and it is preferable that the upper and lower magnetic layers can be formed at one time. Further, the thickness of the upper and lower magnetic layers can be varied by adjusting the number of magnetic sheets.

  In the laminated common mode choke coil and the manufacturing method thereof according to the present invention, the conductor pattern of each layer is located in the film layer region of the nonmagnetic material and the pattern edge is not in contact with the magnetic material. The silver paste can be prevented from flowing into the side. As a result, defects such as a short circuit can be prevented in the lamination of the coil patterns, and the reliability of component manufacture can be improved.

  Further, since the conductor pattern of each layer is a spiral coil pattern, the number of winding turns per layer can be increased, and therefore, a high inductance can be obtained while keeping the number of stacked layers small. In addition, both high inductance and small size can be achieved, and the common mode impedance can be increased.

  Further, since the two coil patterns are laminated in a state where they are alternately meshed with each other, the coupling between the coils is improved. As a result, the normal mode impedance can be kept low and the common mode impedance can be made high. And the fall of the common mode impedance in a high frequency can also be reduced, and a frequency characteristic can be made favorable.

In addition, since the magnetic material in the central part is formed by expanding the area of the corresponding layer and the adjacent layer with a small number of winding turns of the conductor pattern, the magnetic material region approaches the pattern edge of the layer, thereby Coil coupling can be improved satisfactorily and the inductance value can be increased. And since the upper and lower surfaces are pressure-bonded with a plurality of magnetic sheets by a sheet forming method, it has become easier to form the upper and lower surfaces, which previously took a lot of time as viewed from the whole manufacturing process. It will be an improvement. Since no printing or drying process is performed, cracks are eliminated.
Therefore, even if the number of stacked layers is limited, impedance characteristics can be obtained satisfactorily, and the productivity is improved because the yield is not lowered while downsizing.

  FIG. 2 shows a first embodiment of the present invention. In the present embodiment, the laminated common mode choke coil is formed by laminating the insulating film and the conductor pattern 1 in an appropriate order, and providing the vias 2 between the film layers to connect the conductor pattern 1 as appropriate. Two coils are built in, and the two coils are configured to be electrically complementary.

  As the insulating film, portions of the magnetic body 3 and the non-magnetic body 4 are appropriately formed, and the portion of the magnetic body 3 serves as a yoke. That is, the conductor pattern 1 has a spiral shape. In the laminated body, the spiral central portion and the outer portion of the conductor pattern 1 are formed from the magnetic body 3, and the upper and lower outermost layers are also formed as the magnetic body 3 as a central yoke and an outer yoke for two coils. In each layer, the conductor pattern 1 is positioned in the film layer region of the nonmagnetic material 4 so that the pattern edge does not contact the magnetic material 3.

  The spiral conductor pattern 1 of each layer jumps over and connects the adjacent conductor pattern layers in the upper and lower sides, and the two coil patterns are alternately meshed. That is, the spiral conductor pattern 1 is formed on the second, fourth, sixth, and eighth layers, and the second and sixth layer conductor patterns 1 are connected by providing vias 2 that penetrate the third to fifth layers. Then, this is used as one coil A, and the conductive patterns 1 of the fourth and eighth layers are connected by providing vias 2 penetrating the fifth to seventh layers, and this is used as the other coil B.

(Production method)
The manufacturing method of the laminated common mode choke coil of the present embodiment is performed as follows. First, an eighth layer corresponding to the lowermost layer of the coil pattern is formed, and the upper layer side, that is, the seventh layer to the second layer are sequentially stacked. At this time, the conductor pattern 1 is formed in a spiral shape, and vias 2 are appropriately provided between the film layers. Here, the central part and the outer part of the spiral shape of the conductor pattern 1 are formed from the magnetic body 3, and in each layer, the conductor pattern 1 is located in the film layer region of the nonmagnetic body 4 and the pattern edge is the magnetic body 3. The portions of the conductor pattern 1 and the nonmagnetic material 4 and the magnetic material 3, that is, the eighth layer to the second layer are formed by a printing lamination method.

  Next, as shown in FIG. 3, the first layer and the ninth layer, which are upper and lower surfaces, are formed into a film layer having a predetermined thickness by pressure-bonding the magnetic sheet 5 by a sheet forming method. In the manufacture of chip parts, a workpiece laminate of a plurality of sizes is manufactured as a workpiece from the viewpoint of productivity. The same applies to the present invention. After the first layer and the ninth layer are formed, the workpiece laminate is sufficiently dried, cut into individual pieces (chips), and fired. Also, as shown in FIG. 4, the upper and lower surfaces may be formed by pressing a single magnetic material sheet 6 having a predetermined thickness d by a sheet forming method.

  As described above, the laminated body has the central portion and the outer portion of the magnetic body 3, and in each layer, the conductor pattern 1 is positioned in the film layer region of the nonmagnetic body 4 and the pattern edge is not in contact with the magnetic body 3. Therefore, in printing the conductor pattern 1, it is possible to prevent the silver paste from flowing into the lower layer side. As a result, defects such as a short circuit can be prevented in the lamination of the coil patterns, and the reliability of component manufacture can be improved.

  By the way, as a common mode choke coil, the greater the impedance in the common mode, the better the noise removal effect, and the smaller the impedance in the normal mode, the more smoothly the signal can pass. These characteristics are determined by the inductance of the coil (L), the stray capacitance (C) between the two coils, and the coupling. In order to obtain good characteristics, it is necessary to increase L and improve the coupling between the coils, and to reduce C. is there.

  From this point of view, the conductor pattern 1 of each layer is a spiral coil pattern, so that the number of winding turns per layer can be increased, and therefore, a high inductance can be obtained while maintaining a small number of layers. Can do. As a result, both high inductance and miniaturization can be achieved and the common mode impedance can be increased.

  Since the spiral conductor pattern 1 of each layer is not connected in the stacking order, it is connected so as to jump over the adjacent conductor pattern layers vertically adjacent to each other, and the two coil patterns are stacked in an alternately meshing state. The coupling between the coils is improved. As a result, the normal mode impedance can be kept low, and the common mode impedance can be increased. And the fall of the common mode impedance in a high frequency can also be reduced, and a frequency characteristic can be made favorable.

  Here, the film layer (intermediate layer) on which the conductor pattern 1 is provided is formed by a printing lamination method. The upper and lower surfaces are formed by pressure-bonding a plurality of magnetic sheets 5 by a sheet forming method, and the upper and lower surface film layers are formed. In the printing lamination method, the printing and drying steps are performed several times or several tens of times, but in this case, it is not necessary to perform them. Therefore, it is easy to form the upper and lower surfaces, which conventionally took a lot of time from the whole manufacturing process, and the working efficiency is greatly improved. In addition, productivity is improved, and cracks are not generated because printing and drying processes are not performed.

  The work efficiency of the magnetic material sheet 5 can be improved as compared with the printing lamination method by obtaining a predetermined thickness by stacking and pressing a plurality of magnetic sheets. Alternatively, as shown in FIG. 4, a single magnetic sheet having a predetermined thickness may be prepared, and the magnetic sheet 6 may be crimped, and the upper and lower magnetic layers are formed at a time. This is preferable. Further, the thickness of the upper and lower magnetic layers can be varied by adjusting the number of the magnetic sheets 5.

  FIG. 5 shows a second embodiment of the present invention. In the second embodiment, the number of stacked layers is 13 and the central magnetic body 3 is changed. The central magnetic body 3 expands the area of the corresponding layer having a small number of winding turns of the conductor pattern 1. Let it form.

  Even in the second embodiment, the basic configuration is the same as that of the first embodiment, the conductor pattern 1 has a spiral shape, and the laminated body has a spiral central portion and an outer portion of the conductor pattern 1. Are formed from the magnetic body 3 and the upper and lower outermost layers are also the magnetic body 3, which are a central yoke and an outer yoke for the two coils. In each layer, the conductor pattern 1 is located in the film layer region of the nonmagnetic body 4 The portion is not in contact with the magnetic body 3. Further, the spiral conductor pattern 1 of each layer jumps and connects adjacent conductor pattern layers in the upper and lower sides, and the two coil patterns are alternately meshed.

  In the second embodiment, the conductor pattern 1 is formed on the second, fourth, sixth, eighth, tenth, and twelfth layers, and the second and sixth layer conductor patterns 1 are formed on the third to third layers. Vias 2 through 5 layers are provided and connected, and vias 2 through 7th to 9th layers are further provided and connected to the conductive patterns 1 of the sixth and tenth layers to form one coil A, and The conductor patterns 1 of the fourth and eighth layers are provided with vias 2 that penetrate the fifth to seventh layers, and further, the vias 2 that penetrate the seventh to ninth layers of the conductor patterns 1 of the eighth and twelfth layers. The other coil B is provided by connecting and connecting.

  Further, the number of turns of the conductor pattern 1 is set to be small in the ninth layer to the twelfth layer. As shown in FIG. 6, the magnetic body 3 in the central portion is formed by enlarging the area of these film layers. To do. Therefore, in the ninth layer to the twelfth layer, the magnetic body 3 in the center is close to the conductor pattern 1 having a small number of winding turns, so that the coil coupling can be improved satisfactorily and the inductance value can be increased. As a result, even if the number of stacked layers is limited, impedance characteristics can be obtained satisfactorily, and downsizing can be performed.

  Samples were fabricated to demonstrate the effect of the present invention. And the impedance characteristic was evaluated about the sample and the comparative example. Two types of samples were used, and the sample according to the first embodiment (Invention 1) and the sample according to the second embodiment (Invention 2) were manufactured. The comparative example has 13 layers as in the second embodiment, and the ninth to twelfth layers are different from the second embodiment shown in FIG. That is, in the comparative example, as shown in FIG. 7, the portion of the nonmagnetic material 4 is eliminated from the tenth and twelfth layers and the adjacent layers (the ninth and eleventh layers) where the winding turn of the conductor pattern 1 is reduced. The entire region is a magnetic body 3. Therefore, in the comparative example, as shown in FIG. 8, the layer is the outer yoke region itself, and the conductor pattern 1 is embedded in the magnetic body 3 forming the outer yoke.

  When the frequency characteristics of impedance were measured for these samples (present invention 1 and present invention 2) and the comparative example, the results shown in FIG. 9 were obtained. As is clear from the figure, in the first aspect of the present invention, it was confirmed that the normal mode impedance can be lowered and the common mode impedance can be increased. Further, in the present invention 2, it was confirmed that the effect of suppressing the normal mode impedance was higher than that of the comparative example, and that the common mode impedance was about 30% higher.

It is sectional drawing which shows the prior art example of a lamination | stacking common mode choke coil. 1 is a perspective view showing a laminated common mode choke coil according to a first embodiment of the present invention, with each layer separated. FIG. It is a perspective view explaining the manufacturing process of the outermost layer about 1st Embodiment. It is sectional drawing explaining the inside of a laminated body about 1st Embodiment. It is the perspective view which isolate | separated each layer, showing 2nd Embodiment of the lamination | stacking common mode choke coil which concerns on this invention. It is sectional drawing explaining the inside of a laminated body about 2nd Embodiment. It is the perspective view which isolate | separated the 9th layer and subsequent which shows the comparative example with respect to this invention, and is different from FIG. It is sectional drawing explaining the inside of a laminated body about a comparative example. It is a graph which shows the measurement result of an impedance characteristic about two samples which concern on this invention, and a comparative example.

Explanation of symbols

1 Conductor Pattern 2 Via 3 Magnetic Material 4 Non-magnetic Material 5 and 6 Magnetic Material Sheet

Claims (5)

The insulating film and the conductor pattern are laminated in an appropriate order, and vias are provided between the film layers, and the conductor pattern is appropriately connected to incorporate two coils in the laminated body. In a laminated common mode choke coil that adopts a configuration that is complementary to each other,
The conductor pattern has a spiral shape,
The laminated body is formed with a spiral central portion and an outer portion of the conductor pattern from a magnetic body, and the upper and lower outermost layers are also magnetic bodies as a central yoke and an outer yoke for the two coils,
In each layer, the conductive pattern is located in a non-magnetic film layer region, and a pattern edge portion is disposed so as not to contact the magnetic material.   2. The laminated common mode choke coil according to claim 1, wherein the spiral conductive patterns of the respective layers are connected so as to jump over the adjacent conductive pattern layers, and the two coil patterns are alternately engaged with each other.   3. The laminated common mode choke coil according to claim 1, wherein the central magnetic body is formed by enlarging an area of a corresponding layer and an adjacent layer having a small number of winding turns of the conductor pattern. The insulating film and the conductor pattern are laminated in an appropriate order, and vias are provided between the film layers, the conductor pattern is appropriately connected, and two coils are built in the laminated body. The two coils are electrically A method of manufacturing a laminated common mode choke coil configured to operate in a complementary manner,
The conductor pattern has a spiral shape,
The laminated body is formed by forming a spiral central portion and an outer portion of the conductive pattern from a magnetic material, and in each layer, the conductive pattern is located in a non-magnetic film layer region, and a pattern edge is formed on the magnetic material. Arrange it not to touch,
The conductor pattern, the non-magnetic material portion, and the magnetic material portion are formed by a printing lamination method, and the upper and lower surfaces are formed into a film layer having a predetermined thickness by pressure-bonding a magnetic material sheet by a sheet forming method. A method for manufacturing a laminated common mode choke coil. The insulating film and the conductor pattern are laminated in an appropriate order, and vias are provided between the film layers, the conductor pattern is appropriately connected, and two coils are built in the laminated body. The two coils are electrically A method of manufacturing a laminated common mode choke coil configured to operate in a complementary manner,
The conductor pattern has a spiral shape,
In the laminated body, the central portion and the outer portion of the conductive pattern are formed from a magnetic material, and in each layer, the conductive pattern is located in a non-magnetic film layer region and the pattern edge is not in contact with the magnetic material. age,
The conductor pattern, the non-magnetic part and the magnetic part are formed by a printing lamination method, and the upper and lower surfaces are formed by pressing a single sheet of a predetermined thickness magnetic sheet by a sheet forming method. A method for manufacturing a laminated common mode choke coil.

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