JP2868376B2 - LC substrate and manufacturing method thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an LC substrate having a circuit function combining inductance and capacitance, and used for noise reduction or the like in combination with aligned lead wires (pins) in a connector or the like.

[0002]

2. Description of the Related Art A method for reducing noise by adding a circuit combining an inductance (L) and a capacitance (C) to a signal line has been widely known. Even in various industrial and household electronic and electrical devices, noise generated by these devices may enter other devices via the cable connected to the outside, or may enter the devices from outside. In order to prevent this, a circuit combining the inductance L and the capacitance C is provided in the connector portion of the cable.

FIG. 8 shows an equivalent circuit of such a connector. In the figure, reference numeral 800 denotes a lead wire (pin) connected to the cable. L is an inductance, and C is a capacitance provided between the lead wire 800 and the ground wire 801 of the device. By using a connector having the equivalent circuit shown in FIG. 8, input / output of noise through a cable is prevented.

Japanese Patent Laid-Open No. 55-95281, Shokai 5
Japanese Unexamined Patent Publication No. 6-15043 discloses a configuration of a connector having an equivalent circuit shown in FIG. 8 or an equivalent circuit similar thereto. In order to realize an equivalent circuit as shown in FIG. 8, a combination of a ferromagnetic bead such as ferrite and a feedthrough capacitor is usually used for each lead wire.
Here, the through-type capacitor is a capacitor in which electrodes are formed on both surfaces of a dielectric and provided with a through-hole, and a lead wire passing through the through-hole is electrically connected to one of the electrodes. The other electrode is insulated from the lead wire and connected to the ground wire of the connector. However, when the number of lead wires increases, providing a ferrite bead and a penetrating capacitor for each lead wire has a problem that the structure is complicated and manufacturing becomes difficult.

Therefore, the invention disclosed in Japanese Patent Application Laid-Open No. 55-95281 uses a capacitor member in which a through-hole capacitor is integrally formed by providing a through hole and an electrode in a dielectric substrate. Japanese Patent Publication No. 56-15043 uses a ferrite plate having a through hole. By doing so, manufacturing efficiency is improved. 9 and FIG.
It is a figure which shows the example of a structure of the connector described in Unexamined-Japanese-Patent No. 56-15043. FIG. 9 is a view showing each part to be combined, FIG. 10 is a view showing an assembled state, and FIG. 10 (a) is a view of the entire connector.
(B) is an enlarged view of a pin connection portion.

In FIG. 9, reference numeral 900 denotes a connector pin, and 96 denotes a housing in which the lead wires 900 are aligned and fixed, and is made of an insulating material such as plastic. Reference numeral 97 denotes a shield case. 90 is a through hole 94
Conductive layer 9 including side surfaces on ferrite substrate 91 having
3 is an LC substrate on which a feedthrough capacitor 92 is mounted, which is an object of the present invention. The through-type capacitors 92 are attached to the respective through-holes by soldering or the like. The through-type capacitor is not limited to an annular shape, and a part of the annular shape may be missing.

FIG. 1 shows the assembly of the connector shown in FIG.
0 will be described. First, the through-type capacitor 92 is positioned in the through-hole 94 and then passed through a solder furnace. Thereby, the LC substrate is completed. The LC substrate is inserted into the lead wire 900, and solder 95 is attached to the feedthrough capacitor 92 and the connector pin 900, and then passed through a solder furnace. Here, before attaching the feed-through capacitor 92 to the ferrite substrate 91, the ferrite substrate 91 is inserted into the lead wire 900, and further, the feed-through capacitor 92 to which solder is attached is inserted, and then the solder is passed through a solder furnace. Good. Then, a connector is completed by molding a portion of the feedthrough capacitor with a resin and covering it with a shield case.

As shown in FIG. 10B, in the assembled state, the upper electrode 922 of the feedthrough capacitor 92 is formed.
Is connected to the lead wire 900 by the solder 95, and the lower electrode 923 is connected to the conductive layer 93. The conductive layer 93 has a portion 96 extending on the side surface of the ferrite substrate 91, and this portion 96 comes into contact with the shield case. Also, the electrode 923 and the conductive layer 93 below the feedthrough capacitor 92
Must not touch the leads,
As shown, it is provided in a portion excluding the peripheral edge of the through hole.

As described above, by using the LC substrate 90 as shown in FIG. 9, a connector having the equivalent circuit shown in FIG. 8 can be realized, and noise can be attenuated. In the above example, the LC board is used for the connector. However, the LC board can be used for a part that needs to solve the same problem, for example, an IC socket, and is supplied as a single component.

[0010]

The invention described in Japanese Utility Model Laid-Open Publication No. 56-15043 shown in FIGS.
By using a ferrite substrate having a through-hole as a member that performs the inductance function, the production efficiency is improved as compared with combining individual ferrite beads or the like.

However, ferrite substrates are generally fragile and require a certain thickness to be handled as components. Further, it is necessary to provide a through hole in the ferrite substrate, but since the substrate is fragile, it is necessary to increase the distance between the through holes, and there is a problem that a large LC substrate cannot be manufactured. In recent years, miniaturization of electric equipment has been promoted,
The lead wire pitch of connectors and IC sockets also tends to be reduced. For this reason, the LC substrate is required to be capable of accommodating lead wires arranged at a narrow interval, but at present it is not possible to sufficiently cope with the conventional substrate.

Furthermore, ferrite substrates are manufactured by forming a material including a binder and including through holes in anticipation of shrinkage due to firing, and then firing. However, it is difficult to manufacture each ferrite substrate individually. Poor production efficiency. In such a case, multi-cavity dividing after manufacturing a large substrate composed of a plurality of substrates is a general method for improving manufacturing efficiency, but as described above, since the ferrite substrate is fragile,
There is a problem that such a multi-cavity method cannot be applied, and the manufacturing efficiency is poor.

The present invention has been made in view of the above problems, and an object of the present invention is to realize an LC substrate which can be reduced in size and has high manufacturing efficiency, and a method for manufacturing the same.

[0014]

FIG. 1 is a diagram showing a basic configuration of an LC substrate according to the present invention. The LC substrate of the present invention is used by being inserted into a plurality of aligned lead wires 100, and includes a ferrite layer 1 having a plurality of through holes 4 through which the lead wires 100 pass, and a through hole common to the through holes 4. Hole 4
And a capacitor section 2 including a plurality of through-type capacitors 121 provided for each through-hole 4, and one electrode of each of the plurality of through-type capacitors 121 is connected to a corresponding lead wire 100 during use. Being used. It should be noted that different types of capacitors may be used in combination for each lead wire. In order to achieve the above-mentioned object, the ceramic substrate 3 is provided so as to have a common through hole with the through hole 4 through which the lead wire 100 penetrates, and to be formed integrally with the ferrite layer 1 and the capacitor portion 2.

[0015]

The weakness of the ferrite layer 1 hinders miniaturization of the LC substrate and improvement of manufacturing efficiency. Therefore, a member that reinforces the brittleness of the ferrite layer 1 is added. However, it is necessary that the ferrite layer 1 and the capacitor portion 2 can be firmly fixed, and that the ferrite layer 1 is manufactured by firing, so that it can withstand firing. It is. Therefore, in the present invention, the porcelain substrate 3 is added, and the porcelain substrate 3, the ferrite layer 1 and the capacitor portion 2 are integrally formed.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The capacitor portion is formed by mounting individual feedthrough capacitors on a previously fired porcelain substrate or a ferrite layer, or as described in the aforementioned Japanese Patent Application Laid-Open No. 55-9528.
It is made by any method of providing a through hole and an electrode on a dielectric plate and integrally forming the same as disclosed in Japanese Patent No.
Here, first, an embodiment of integrally forming will be described.

FIG. 2 is a perspective view for explaining an LC substrate manufacturing process in the first embodiment, and the first embodiment will be described with reference to FIG. First, a material obtained by firing a porcelain substrate, a ferrite layer, and a dielectric substrate for a capacitor, to which a binder and the like are added, is dried and then formed into a sheet. This is called a green sheet. Each green sheet is subjected to press forming including through holes in anticipation of shrinkage due to firing. A conductive paste is printed on the entire surface of the green sheet for the capacitor except for the periphery of the through hole on one surface. This becomes the common electrode. Then, a conductive paste is printed on a portion of the side surface of the capacitor green sheet which is to be an extension connected to the common electrode. Further, a conductive paste is printed on the other surface in a pattern separated from each other with the through hole as a center. Although this pattern is shown as an annular shape in the figure, it may have another shape or a part of the ring may be missing. In addition, the part which becomes a common electrode may be printed on the green sheet of the ferrite layer.

FIG. 2A shows a state in which the above-mentioned steps have been completed. Reference numerals 21 and 23 denote a ferrite layer and a green sheet of a porcelain substrate, respectively. It is formed to have a predetermined shape. 221 is a green sheet for a capacitor,
Similarly, the through hole 224 and the outer shape are formed. FIG.
(a) is a perspective view seen from the lower side on which a common electrode is formed, and 222 is a printed surface of a conductive paste corresponding to the common electrode. As shown in the drawing, printing is performed except for the peripheral portion of the through hole 224. Reference numeral 225 denotes a printed surface of a conductive paste corresponding to an extension of the common electrode.

Each green sheet shown in FIG. 2A is aligned with a jig or the like and then bonded with an adhesive or the like.
FIG. 2B is a perspective view of the bonded state, as viewed from the upper surface side of the capacitor green sheet. As shown in the figure, on the upper surface of the capacitor green sheet 221, mutually separated electrodes centering on the through holes are printed. This electrode may be printed after bonding.

The material shown in FIG. 2B is fired at a temperature in consideration of the characteristics of each raw material for a predetermined time to complete an LC substrate. In FIG. 2, the porcelain substrate 23, the ferrite layer 21,
Although the capacitor portion 22 is bonded in this order, the ferrite layer 21, the porcelain substrate 23, and the capacitor portion 22 may be bonded in this order, or the porcelain substrate 23, the capacitor portion 22, and the ferrite layer 21 may be bonded in this order. However,
When the porcelain substrate 23, the capacitor portion 22, and the ferrite layer 21 are bonded in this order, the capacitor portion 22 is located in the middle, so that connection between each through-type capacitor of the capacitor portion and the lead wire cannot be performed as in the related art. Therefore, an electrode is formed by applying a conductive paste to each through hole of the capacitor green sheet in a form continuous with each electrode, and when a lead wire is inserted, it is necessary to connect the electrode on the inner wall of the through hole with solder or the like. .

In the first embodiment, 3
The two layers are formed of green sheets, integrated and fired. In the second embodiment, a ceramic substrate which has been fired in advance is used. In the second embodiment, first, a porcelain substrate is manufactured. This is performed by forming a green sheet and then firing the same as in the first embodiment. The subsequent steps are the same except that the porcelain substrate has already been fired.

In the first embodiment, the materials of the porcelain substrate, the ferrite layer, and the dielectric material plate of the capacitor portion had to be selected so as to match the firing temperature. These restrictions are eliminated, and the degree of freedom in material selection is increased. In the third embodiment, a ferrite layer is formed not by green sheets but by printing a ferrite paste, and a plurality of LCs are simultaneously formed.
A multi-piece manufacturing process for manufacturing and dividing a substrate is performed.

First, a through hole is formed in a green sheet of a porcelain substrate from which a plurality of LC substrates can be manufactured. At this time, a plurality of external shapes are formed, and after completion, snaps for dividing the respective LC substrates are processed at predetermined positions. The green sheet thus manufactured may be used in the next step as it is, or may be used in the next step after firing. Here, the description will be made assuming that the product is fired.

A ferrite paste is printed on the above-mentioned porcelain substrate in a required shape, that is, a portion excluding a through-hole portion.
This printing is performed by screen printing. Further, a portion to be a common electrode is printed with a conductive paste. Once baked, an intermediate product can be obtained by adding a porcelain substrate to the ferrite plate shown in FIG. 9 with a conductive layer formed thereon. After printing, baking is completed.

In the fourth embodiment, a paste is printed instead of the capacitor green sheet. The common electrode is printed on a combination of a porcelain substrate and a ferrite layer manufactured in the form of a green sheet or a substrate that has already been fired, and then the dielectric material paste of the capacitor is printed, and the electrodes are printed thereon. . Then, by firing this, an LC substrate is completed.

In the above embodiment, the capacitor portion is formed integrally by green sheet and printing. FIG. 3 shows a state where the lead wire is inserted into the LC substrate thus formed. is there. In FIG. 3A,
21 is a ferrite layer, and 23 is a porcelain substrate. 2
21 is a dielectric material of the capacitor part, 222 is a common electrode, and 223 is an electrode for each through hole. Reference numeral 25 denotes solder, which connects the electrode 223 and the lead wire 200.

FIG. 3B is an enlarged view of only the capacitor portion. As shown in the drawing, the common electrode 222 has a through-hole portion where a portion having a diameter t ₂ larger than the diameter t ₁ of the through-hole is removed. . When supplied as an LC substrate and then inserted into aligned lead wires, soldering is performed between the lead wire 200 and the electrode 223 at that time. For example, a connector incorporating the LC substrate is manufactured. Occasionally, baking and soldering of the LC substrate may be performed with the lead wire incorporated.

In the above embodiment, the capacitor portion is formed in layers by green sheets or printing. In the fifth embodiment described below, the capacitor portion is formed by combining individual feedthrough capacitors. FIG. 4 is a diagram for explaining a manufacturing process of the LC substrate in the fifth embodiment, and FIG. 5 is a cross-sectional view of a part of the completed LC substrate.

In the fifth embodiment, first, as shown in FIG.
And a ferrite layer 41 are prepared. This naturally has a through hole 4
4 are provided. Next, as shown in FIG.
A conductive paste corresponding to the conductive layer 422 is printed on the surface of the ferrite layer 41. At this time, the conductive paste for the extension 425 is printed on the side surface. Then, if this is fired, a ceramic substrate obtained by adding a conductive layer to the ferrite plate of FIG. 9 provided with a conductive layer as described in the third embodiment can be obtained. This is also stronger than that of FIG. 9 because the porcelain substrate 43 is provided.

Next, as shown in FIG. 4 (c), a through-type capacitor 421 having solder adhered to the electrodes is bonded with the through-holes aligned. Then it is completed through a solder furnace. The cross section of the completed LC substrate is as shown in FIG. 43 is a porcelain substrate, 41 is a ferrite layer, 422 is a conductive layer, and 425 is an extension of the conductive layer. 421 is a feedthrough capacitor. 427 is an electrode connected to the lead wire, 428 is a dielectric, and 429 is an electrode connected to the conductive layer 422. Reference numeral 426 denotes solder for connecting the electrode 429 and the conductive layer 422.

The above is the embodiment of the LC substrate of the present invention and the method of manufacturing the same. In any of the embodiments, a large number of LC substrates are divided after forming a large number of LC substrates on one substrate as in the third embodiment. Individual production is possible, and production efficiency can be improved. Next, an example in which the LC substrate of the present invention is used for a connector and an IC socket will be described.

FIG. 6 is a sectional view of a part of a connector incorporating the LC substrate of the present invention. In the figure, 600 is a lead wire (connector pin), and 66 is a lead wire 60.
This is a resin that fixes 0. 67 is a shield case, which is connected to the ground of the device. The LC substrate is composed of a ferrite layer 61, a porcelain substrate 63, a conductive layer 622, a dielectric plate 621 for a capacitor, and an electrode 623. The top is molded with a resin 68. Reference numeral 625 denotes an extension of the conductive layer 622.
To the ground of the conductive layer 622.

FIG. 7 shows an LC socket according to the present invention in a normal IC socket.
An example is shown in which a socket made of a substrate is further inserted to reduce noise. In the figure, reference numeral 700 denotes an IC, 701 denotes a normal IC socket, and 702 denotes wiring on a printed circuit board. Normally, only this is used, but here, the LC IC socket 70 is further inserted into the IC socket 701, and the IC 700 is inserted therein.

FIGS. 1 and 2 show an IC socket 70 made of LC.
A pin is provided below the porcelain substrate of the LC substrate of the present invention shown in FIG. The pins are combined and integrally formed before firing the porcelain substrate. When the electrode on the upper surface of the capacitor section is inserted, it must contact the foot of the IC 700, and the electrode extends to the inner wall of each through hole. The common electrode is connected to a pin a connected to the circuit ground.

The LC IC socket shown in FIG. 7 can be used as it is because the porcelain substrate is strong. The LC socket may be directly mounted on the board without using the conventional IC socket 701.
Although the embodiment of the present invention has been described above, the present invention is to add a porcelain substrate to a conventional ferrite substrate and a capacitor part, various modifications are possible, and various methods of manufacturing the same are possible. Although not all of them can be shown as examples, a combination or manufacturing method of a part of each example is possible.

[0036]

According to the present invention, a small LC substrate can be easily produced with high production efficiency, and the finished product can be easily handled and applied to a wide range.

[Brief description of the drawings]

FIG. 1 is a diagram showing a basic configuration of an LC substrate of the present invention.

FIG. 2 is an explanatory diagram of a manufacturing process of the LC substrate of the first embodiment.

FIG. 3 is a cross-sectional view showing a state where the LC substrate of the first embodiment is inserted into and fixed to a lead wire and a capacitor portion at that time.

FIG. 4 is an explanatory diagram of an LC substrate manufacturing process according to a fifth embodiment.

FIG. 5 is a sectional view of an LC substrate according to a fifth embodiment.

FIG. 6 is a partial cross-sectional view showing a connector incorporating the LC substrate of the present invention.

FIG. 7 is a diagram showing an example in which the LC substrate of the present invention is applied to an IC socket.

FIG. 8 is a diagram showing an equivalent circuit of a connector to which an LC circuit is added.

FIG. 9 is a perspective view showing the configuration of a connector in which a conventional ferrite substrate is combined with a feedthrough capacitor.

FIG. 10 is a sectional view of the conventional example of FIG. 9;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Ferrite layer 2 ... Capacitor part 3 ... Porcelain board 4 ... Through-hole 100 ... Lead wire

Continuation of front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H05K 9/00

Claims (13)

(57) [Claims] 1. An LC substrate used by being inserted into a plurality of aligned lead wires (100), wherein a plurality of through holes (4) through which the lead wires (100) pass.
And a capacitor part (2) having a through hole common to the through hole (4) and comprising a plurality of through capacitors provided for each of the through holes (4). And the lead wire (10) to which one electrode of the plurality of feedthrough capacitors corresponds.
0) The LC substrate used in connection with 0) has a common through hole with the through hole (4) through which the lead wire (100) passes, and includes the ferrite layer (1) and the capacitor section (2). Porcelain substrate (3) integrally formed with
An LC substrate comprising: 2. The ferrite layer (1) is provided on the porcelain substrate (3), and the capacitor part (2) is provided on the ferrite layer (1). 2. The LC substrate according to 1. 3. The ferrite layer (1) is provided on one surface of the porcelain substrate (3), and the capacitor part (2) is provided on the other surface of the porcelain substrate (3). The LC substrate according to claim 1, wherein: 4. The capacitor part (2) is provided on the porcelain substrate (3), and the ferrite layer (1) is provided on the capacitor part (2). The LC substrate according to 1. 5. The device according to claim 1, further comprising a common electrode connected to each electrode of the feedthrough capacitor that is not connected to the lead wire. The described LC substrate. 6. The capacitor part (2) is a layered dielectric having a plurality of through holes through which the lead wire (100) penetrates, and electrodes are provided on both surfaces of the layered dielectric, respectively. The LC substrate according to claim 1, wherein the electrodes are provided independently of each other around the through hole. 7. The method for manufacturing an LC substrate according to claim 1, wherein the material of the porcelain substrate (3) is formed into a sheet, and then formed including the through hole. And forming a portion corresponding to the ferrite layer (1) and the capacitor portion (2) on the porcelain substrate green sheet, and firing the whole. A method for manufacturing an LC substrate, comprising: 8. The method of manufacturing an LC substrate according to claim 1, wherein the porcelain substrate (3) having the through holes is manufactured by firing. (3) A method of manufacturing an LC substrate, comprising: a step of forming a portion corresponding to the ferrite layer (1) and the capacitor section (2) on the top; and a step of firing the whole. 9. The ferrite layer (1) is formed by forming a material of the ferrite layer (1) into a sheet and then forming the ferrite layer (1) including the through holes to form a ferrite layer green sheet. 9. The method according to claim 7, further comprising: aligning the ferrite layer green sheet and bonding the ferrite layer green sheet to a portion including the porcelain green sheet or the porcelain substrate (3). 10. 3. The method for manufacturing an LC substrate according to item 1. 10. The step of forming a portion corresponding to the ferrite layer (1) includes printing a ferrite paste in a predetermined shape on a portion including the porcelain green sheet or the porcelain substrate (3). Claim 7 or 8
The method for manufacturing an LC substrate according to any one of the above items. 11. Forming a portion corresponding to the capacitor portion (2) by forming a dielectric material of the feedthrough capacitor into a sheet shape and forming the capacitor portion green sheet including the through hole. And a step of printing a common electrode with a conductive paste on the entire surface excluding the periphery of the through hole on one surface of the capacitor part green sheet, and a step of printing a common electrode on the other surface of the capacitor part green sheet as a center of the through hole. A step of printing the separated electrode pattern with a conductive paste, and aligning the capacitor part green sheet with the porcelain green sheet or the porcelain substrate (3)
11. A method of manufacturing an LC substrate according to claim 9, further comprising the step of: 12. The step of forming a portion corresponding to the capacitor portion (2) includes printing a common electrode with a conductive paste on an arbitrary surface excluding a peripheral edge of a through hole in a portion including the porcelain green sheet; 10. The method according to claim 9, further comprising the steps of: printing a paste of a dielectric material of the die capacitor over the entire surface except for the through-holes; and printing electrode patterns separated from each other around the through-holes with a conductive paste. 11. The method for manufacturing an LC substrate according to any one of items 10. 13. The method of manufacturing an LC substrate according to claim 7, wherein a plurality of LC substrates are manufactured as a single substrate and divided after completion.