JP3409998B2 - Chip type inductor array - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chip type inductor array for reducing crosstalk between inductors.

[0002]

2. Description of the Related Art In recent years, digital signal processing technology has made rapid progress, and its processing speed has reached 100 to 200 MHz in terms of CPU clock frequency. Furthermore, digital signal processing technology is used in all electronic devices. Generally, since a digital signal of an electronic device contains many harmonic components, the harmonics flow out to a cable connected to another device and cause unnecessary radiation as noise.
To avoid this, an inductor is inserted in each signal line near the cable connector.

On the other hand, in recent years, miniaturization and integration of electronic devices have progressed, and accordingly, electronic devices have been compounded or arrayed. The inductors described above can be arrayed and further downsized to a chip type.

An example of such a chip type inductor array is shown in FIGS. FIG. 2 is a perspective view showing the structure of the chip-type inductor array, and FIG. 3 is an exploded perspective view of a main part.
This inductor array 1 is one in which three coils (inductors) 10 are laterally arranged in one magnetic body, and each coil 10 is formed by laminating a plurality of ferrite green sheets 12 printed with a conductor paste 11. Configured. The printed conductor paste 11 is vertically connected through through holes 13 to form a circular pattern that circulates vertically. Both ends of the circular pattern are connected to a connector or a signal line of an electronic device through connection electrodes 14. To be done.

[0005]

However, in the chip-type inductor array 1 as described above, when the space between the adjacent coils 10 is narrow, each coil 1 is separated.
There is a problem that the magnetic flux generated from 0 is coupled to another coil 10 to cause crosstalk.

In view of the above problems, it is an object of the present invention to provide a chip-type inductor array which can suppress crosstalk between inductors and can set a narrow interval between inductors.

[0007]

In order to achieve the above object, the present invention provides a plurality of inductors made of a spiral conductive material and a predetermined ceramic material filled in a predetermined space containing the plurality of inductors. A substantially rectangular parallelepiped element body formed by, and connected to both ends of each inductor,
A plurality of pairs of connection electrodes formed on the outer surface of the element body, wherein the plurality of inductors have central axes of the spirals substantially parallel to each other, and the central axes of the spirals are a pair of opposing pairs of the element body. In a chip-type inductor array arranged side by side so as to intersect substantially at right angles to the main surface, the element body is
A plurality of spiral-shaped conductive materials that form the plurality of inductors, a conductive material of the inductors, and the ceramic material
A chip-type inductor array composed of a high-permeability magnetic material arranged in a predetermined region along the shape of the conductive material between the two and a low-permeability ceramic material forming the other portion is proposed. To do.

According to the chip-type inductor array, the magnetic fluxes generated around the conductive material of each inductor are gathered together and move from one end of the spiral to the outside along the central axis of the spiral inside the inductor. It flows in the opposite direction to the other end of the spiral, and flows inside the spiral along the main path again along the central axis of the spiral. However, the conductor between the conductive material of the inductor and the ceramic material is
The magnetic material having a high magnetic permeability is arranged only in a predetermined region along the shape of the electric material, and the other portions in the element body are made of the ceramic material having a low magnetic permeability, so that the ratio of the magnetic flux flowing through the main path is reduced, The ratio of the magnetic flux flowing in the magnetic material of high magnetic permeability arranged near the conductive material increases. As a result, the ratio of the magnetic flux that reaches the adjacent inductors is reduced, and the coupling of the magnetic flux to the adjacent inductors is suppressed.

According to a second aspect of the present invention, the chi
In the up-type inductor array, the element body is the first transparent element.
A first ceramic material sheet having magnetic susceptibility and the first ceramic
The inductor is provided on the main surface of the Mick material sheet.
Constituting conductive material layer, the conductive material layer and the first ceramic
According to the shape of the conductive material layer between the
A first magnetic field arranged in a predetermined region and having a magnetic permeability larger than the first magnetic permeability;
And a second ceramic material layer having a magnetic permeability of 2
We propose a new chip-type inductor array.

The element body of the chip-type inductor array is
A first ceramic material sheet having one magnetic permeability;
The inductor is provided on the main surface of the ceramic material sheet.
A conductive material layer constituting the data source, the conductive material layer and the first cell.
Following the shape of the conductive material layer between the
Is located in a predetermined area and is larger than the first magnetic permeability.
And a second ceramic material layer having a second magnetic permeability.
It will be.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below. FIG. 1 is an external perspective view showing a chip-type inductor array according to an embodiment of the present invention, FIG. 4 is an exploded perspective view of a main part, and FIG.
Is a plane sectional view, and FIG. 6 is a sectional view taken along the line AA shown in FIG. In the figure, reference numeral 2 denotes a chip-type inductor array, which is formed of a substantially rectangular parallelepiped element body 21 made of a low-permeability magnetic ceramic and a pair of opposing side surfaces of the element body 3 with a predetermined space therebetween. Pair of connection electrodes 22a to 22f
It consists of and.

Further, three coils (inductors) L1, L2, L3 made of a spiral conductor are formed inside the element body 21, and both ends of these coils L1 to L3 are formed on the side surfaces of the element body 21, respectively. Connected to the connected connection electrodes 22a to 22f.

The central axes of the spirals of the coils L1 to L3 are parallel to each other and intersect the element body 21 at substantially right angles to the upper and lower surfaces thereof.

Further, most of the inside of the element body 21 is formed of a magnetic material 21a having a low magnetic permeability, and the coils L1 to L3.
The magnetic material 21b having a high magnetic permeability is disposed only in a predetermined region near the.

Here, the magnetic material 21a having a low magnetic permeability which constitutes most of the inside of the element body 21 is lower than the magnetic material 21b having a high magnetic permeability which is arranged only in the vicinity of the conductive material forming the coils L1 to L3. Any material having magnetic permeability can achieve the object of the present invention and may be a non-magnetic material.

Explaining the above-mentioned structure in more detail, the element body 21 includes conductor patterns 23a1, 23a2, 23a3 to 23a-23.
A plurality of rectangular low-permeability magnetic material sheets 24a to 24e in which e1, 23e2, and 23e3 are formed and a rectangular low-permeability magnetic material sheet 24f in which a conductor pattern is not formed are laminated and integrally formed. .

Further, the conductor patterns 23a1, 23a2, 23
On the low-permeability magnetic material sheets 24a-24e on which a3-23e1, 23e2, and 23e3 are formed, the low-permeability magnetic material sheets 24a-24e and the conductor patterns 23a1, 23a are formed.
2, 23a3 to 23e1, 23e2, 23e3 have a predetermined thickness and have conductor patterns 23a1, 23a2, 23a3
˜23e1, 23e2, 23e3, and a wide magnetic material pattern 25a1, 25a2, 25a3 with a high magnetic permeability, which has almost the same shape as 25e3
1, 25e2 and 25e3 are provided.

Conductor patterns 23a1, 23a2, 23a3-2
Each of 3e1, 23e2, and 23e3 is made of a predetermined conductor and is made of a magnetic material pattern 25a1, 25a2, 25 having high magnetic permeability.
a3 to 25e1, 25e2 and 25e3 are formed on the low magnetic permeability sheets 24a to 24e, and the conductor patterns 23a1, 23a2, 23a3 to 23e1, 23e2 and 23e3 are low magnetic permeability sheets 24a to 24e. Is formed in a substantially U shape or a substantially I shape so as to be substantially parallel to the predetermined 3 to 4 sides.

These conductor patterns 23a1, 23a2, 2
3a3 to 23e1, 23e2, and 23e3 are conductively connected to each other through a through hole 26 so as to have a spiral shape, and three coils L1, L2, and L3 are configured.

That is, the conductor patterns 23a1, 23b1, 23
The coil L1 is formed by c1, 23d1, 23e1, the coil L2 is formed by the conductor patterns 23a2, 23b2, 23c2, 23d2, 23e2, and the conductor patterns 23a3, 2
A coil L3 is formed by 3b3, 23c3, 23d3 and 23e3.

Further, these coils L1, L2, L3
The conductor patterns of the portions corresponding to both ends of the element body 21 are formed so as to be exposed on the side surfaces of the element body 21, and the conductor patterns exposed on the side surfaces of the element body 21 are conductively connected to the connection electrodes 22a to 22f.

Next, the manufacturing procedure of the inductor array 2 of this embodiment will be described in detail. First, NiO, ZnO, CuO
(Zn rich) was weighed, put into a ball mill together with water for mixing and dispersion, taken out from the ball mill and dried, and then heated in air at 80 ° C. for 2 hours for calcination. Then put it again into the ball mill with water and crush it for 15 hours.
It was taken out from the ball mill and dried to obtain a high-permeability porcelain powder. An organic binder containing polybutyral as a main component and an organic solvent were added to this high-permeability porcelain powder and kneaded to obtain a high-permeability porcelain slurry having a viscosity of 4200 cp.

Further, NiO, ZnO and CuO (Ni rich) are weighed and put into a ball mill together with water to mix,
Disperse, take out from the ball mill, dry, heat in air at 80 ° C. for 2 hours to calcinate, then put into a ball mill with water again, crush for 15 hours, take out from the ball mill, dry and reduce low permeability. After obtaining the magnetic susceptibility porcelain powder, an organic binder containing polybutyral as a main component and an organic solvent were added and kneaded to obtain a low-permeability porcelain slurry having a viscosity of 4200 cp.

On the other hand, Ag powder, ethyl cellulose, α-
An Ag paste prepared by kneading terpineol and butyl carbitol acetate was prepared.

Next, the polyethylene terephthalate base film is conveyed horizontally, and the above-mentioned low-permeability porcelain slurry is applied to this base film by the doctor blade method. This was dried and then peeled off and cut into a square of 110 mm square to form a sheet having a thickness of 40 μm, and a plurality of these sheets were prepared.

Further, a frame-shaped stainless frame in which a 100 mm square window is surrounded by a width of 15 mm is prepared. Small holes for positioning in a printing machine or the like are provided at the corners of this frame. The sheet is attached to this frame, and a high-permeability porcelain slurry is printed to print magnetic material patterns 25a1, 25a2, 25a3 to 25e1, 25e2, 25e3.
And dry it. After that, the through hole is punched at a predetermined position of the sheet with a through hole die to form a green sheet having the through hole.

Next, the conductor patterns 23a1, 23a2, 23a3 to 23e1, 23e are printed on the green sheet by using a printing machine.
2,23e3 is formed. A plurality of pins for positioning the frame are provided at a station for arranging an object to be printed of a separately prepared printing press. The pin is inserted into the small hole of the frame to determine the printing position, and the Ag paste is used for the green sheet to form the conductor patterns 23a1, 23a2, 23a3 to 23e1, 23e2, 23e3 having the above-described shapes.
Is formed by screen printing. At this time, the corresponding conductor patterns 23a1, 23a2, 23a3 are provided on the green sheet.
23e1, 23e2, and 23e3 are formed in a matrix with a plurality of vertical and horizontal rows.

Thereafter, the green sheets are laminated and pressure-bonded in the order shown in FIG. 4 so that the conductor patterns 23a1, 23a2, 23a3 to 23e1, 23e2, 23e3 are vertically overlapped. As a result, the upper and lower conductor patterns 23a1 and 23a
2, 23a3 to 23e1, 23e2, 23e3 are through holes 2
Conductive connection is made via 6 to form coils L1, L2, L3.

Next, the above-mentioned rectangular parallelepiped chips were cut and fired at a temperature of 900 ° C. for 2 hours. Furthermore, the conductor patterns 23a1, 23a2, 23a3 to 23e1, 23e2, 2
By forming connection electrodes 22a to 22f which are electrically connected to the ends of 3e3, the inductor array 2 having the three coils L1, L2 and L3 is configured.

According to the present embodiment having the above-mentioned configuration,
As shown in FIG. 7, the conductor patterns 23a1, 23a2, 23a3 to 23e1, 23e2, 23 of the coils L1, L2, L3.
The magnetic flux φ1 generated around e3 gathers together,
Inside the coils L1, L2, and L3, the spiral moves from one end to the outside along the central axis of the spiral, moves in the opposite direction to that at the inside to reach the other end of the spiral, and the inside of the spiral again has the central axis of the spiral. Follow the main route along. However, the conductor patterns 23a1, 23a2 of the coils L1, L2, L3,
High magnetic permeability magnetic material patterns 25a1, 25a2, 25a3 to 25e1, 2 only in the vicinity of 23a3 to 23e1, 23e2, and 23e3.
High magnetic permeability magnetic material 2 formed by 5e2 and 25e3
1b is arranged and the other parts in the element body 21 are made of the magnetic material 21a having a low magnetic permeability, the magnetic flux φ2 flowing through the main path is reduced, and the conductor patterns 23a1, 23a2, 23a3 to 23e.
The ratio of the magnetic flux φ1 flowing in the magnetic material 21b having a high magnetic permeability arranged near 1, 23e2, 23e3 increases. As a result, the ratio of the magnetic flux reaching the adjacent coils L1, L2, L3 is reduced, and the coupling of the magnetic flux to the adjacent coils L1, L2, L3 is suppressed.

As a result, when different signals are applied to the coils L1, L2 and L3, crosstalk between them is suppressed. In addition, coils L1 and L
Even if the distance between L2 and L3 is set to be narrow, the occurrence of crosstalk can be suppressed.

The above-mentioned embodiment is an example, and the present invention is not limited to this.

[0033]

As described above, according to the chip type inductor array of the present invention, the conductive material of the inductor and the ceramic
A magnetic material having a high magnetic permeability is disposed only in a predetermined region along the shape of the conductive material between the magnetic material and the other material, and the other parts in the element body are made of a ceramic material having a low magnetic permeability. , The ratio of the magnetic flux flowing in the magnetic material having a high magnetic permeability disposed in the vicinity of the conductive material increases, and the ratio of the magnetic flux reaching the adjacent inductors decreases, so that the coupling of the magnetic flux to the adjacent inductors is suppressed. Therefore, even if different signals are applied to the adjacent inductors, crosstalk between them is suppressed. Furthermore, even if the interval between adjacent inductors is set narrower than in the conventional case, the occurrence of crosstalk can be suppressed.

[Brief description of drawings]

FIG. 1 is an external perspective view showing a chip inductor array according to an embodiment of the present invention.

FIG. 2 is a perspective view showing the structure of a conventional chip-type inductor array.

FIG. 3 is an exploded perspective view of essential parts showing a conventional chip-type inductor array.

FIG. 4 is an exploded perspective view of essential parts showing a chip-type inductor array according to an embodiment of the present invention.

FIG. 5 is a plan view showing a chip inductor array according to an embodiment of the present invention.

6 is a cross-sectional view taken along the line AA shown in FIG.

FIG. 7 is a diagram illustrating a crosstalk suppressing operation according to an embodiment of the present invention.

[Explanation of symbols]

2 ... Chip type inductor array, 21 ... Element body, 21a ...
Low magnetic permeability magnetic material, 21b ... High magnetic permeability magnetic material, 22a
22f ... Connection electrodes, 23a1, 23a2, 23a3 to 23e
1, 23e2, 23e3 ... Conductor pattern, 24a to 24f ...
... Low permeability magnetic material sheet, 25a1, 25a2, 25a3 ~
25e1, 25e2, 25e3 ... High permeability magnetic material pattern,
26 ... Through hole, L1, L2, L3 ... Coil (inductor).

Claims (2)

(57) [Claims] 1. A substantially rectangular parallelepiped element body formed by a plurality of inductors made of a spiral conductive material and a predetermined ceramic material filled in a predetermined space containing the plurality of inductors, and each of the inductors. Connected to both ends,
A plurality of pairs of connection electrodes formed on the outer surface of the element body, wherein the plurality of inductors have central axes of the spirals substantially parallel to each other, and the central axes of the spirals are a pair of opposing pairs of the element body. in the chip type inductor array are juxtaposed so as to cross substantially perpendicularly to the principal surface, wherein the body includes a conductive material of a plurality of helical shape constituting the plurality of inductors, the conductive material of the inductor the Sera
A predetermined area along the shape of the conductive material between
2. A chip-type inductor array comprising: a magnetic material having a high magnetic permeability, which is disposed in the above, and a ceramic material having a low magnetic permeability, which forms the other portion. 2. The element body is a first cell having a first magnetic permeability.
Of the lamic material sheet and the first ceramic material sheet
Conductive material layer provided on the main surface to form the inductor
Of the conductive material layer and the first ceramic material sheet
Is disposed in a predetermined region along the shape of the conductive material layer between
And having a second magnetic permeability greater than the first magnetic permeability
Two ceramic material layers are laminated Characterized by
The chip-type inductor array according to claim 1.