JPH06120038A - Hybrid integrated circuit - Google Patents

Abstract

PURPOSE:To make a hybrid intgerated circuit capable of decreasing the magnetic resistance around a choke coil and the leakage flux while increasing inductance value. CONSTITUTION:Within the title hybrid integrated circuit wherein a winding coil comprising a spirally wound up conductor, a magnetic-body-made core fitted to the inside of this coil and a choke coil 14 having electrodes 14a provided on both ends of the core are mounted on a substrate 11, a magnetic body 12 is provided at least beneath the choke coil 14 on the substrate 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hybrid integrated circuit having a surface mounting choke coil mounted on a substrate.

[0002]

2. Description of the Related Art Conventionally, a winding coil in which a conductive wire is wound in a spiral shape, a columnar ferromagnetic core mounted inside the winding coil, and both ends of the ferromagnetic core are provided. When mounting a surface mounting choke coil composed of electrodes on a substrate, for example, a chip type RFC (Radio Frequency Cho-ke), simply form electrode soldering lands with a conductor pattern on a ceramic insulating substrate, It was mounted by soldering on this soldering land.

That is, the conventional hybrid integrated circuit is shown in FIG.
As shown in (A) and (B), for example, a plurality of pairs of left and right soldering lands 2a and 2b are formed by a conductor pattern on a ceramic insulating substrate 1, and between the pair of soldering lands 2a and 2b. The choke coil 3 of the surface mounting component is placed, and the solder 4 is attached to the electrode 3a of the choke coil 3.
Solder by reflow solder.

[0004]

However, in the conventional hybrid integrated circuit, the surface mounting choke coil 3, which is, for example, a chip type RFC, is surrounded by an insulating substrate 1 made of air or ceramics, and particularly air is permeable. Since the magnetic susceptibility is 1, the magnetic resistance is large and the leakage magnetic flux is large. As a result, there is a problem that the inductance value of the circuit becomes small.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a hybrid integrated circuit in which the magnetic resistance and leakage magnetic flux around the choke coil are reduced and the value of the inductance is increased. .

[0006]

In order to solve the above-mentioned problems, a hybrid integrated circuit according to the present invention has a winding coil formed by spirally winding a conductor wire and a magnetic coil mounted inside the winding coil. In a hybrid integrated circuit in which a choke coil having a body core and electrodes provided at both ends of the magnetic core is mounted on a substrate, the magnetic body is provided at least below the choke coil on the substrate.

Further, it is desirable that the magnetic body is formed so as to extend to the outside of the choke coil.

Further, the magnetic body may be formed into a plurality of thin strips at predetermined intervals along the direction between the electrodes of the choke coil.

A groove may be formed in the substrate below the choke coil, and the magnetic body may be provided in the groove.

[0010]

In the present invention having the above structure, since the magnetic material is provided at least under the choke coil on the substrate, the magnetic flux generated by the choke coil passes through the magnetic material. Therefore, the magnetic resistance and the leakage magnetic flux decrease, and the inductance value increases.

Further, when the above magnetic body is formed so as to extend to the outside of the choke coil, the magnetic flux becomes easier to pass through, and the magnetic resistance and the leakage magnetic flux can be further reduced.

Further, by forming the magnetic body into a plurality of thin strips at predetermined intervals along the direction between the electrodes of the choke coil, it is possible to reduce the eddy current loss of the choke coil.

The magnetic resistance and the leakage magnetic flux can be further reduced by forming a groove in the substrate below the choke coil and providing a magnetic material in the groove.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

1A and 1B are a vertical sectional view and a plan view showing a first embodiment of a hybrid integrated circuit according to the present invention. 1A and 1B, a hybrid integrated circuit 10 has a rectangular thick-film ferromagnetic layer 12 made of ferrite, YIG or the like formed on an insulating substrate 11 made of ceramics, and has a conductor pattern, for example, left and right. A plurality of pairs of soldering lands 13a and 13b are formed, and the choke coil 14 of the surface mounting component is placed between the pair of soldering lands 13a and 13b.
4a is soldered by the reflow solder of the solder 15.

That is, in the portion where the choke coil 14 is mounted on the insulating substrate 11, the thick film ferromagnetic layer 12 is formed in advance by a screen printing method or the like in a larger area than the installation space of the choke coil 14. The soldering lands 13a and 13b are formed by using, for example, a thick film copper conductor so as to sandwich the thick film ferromagnetic layer 12.

The choke coil 14 is, for example, a chip-type RFC, and is made of a columnar ferromagnetic material composed of a winding coil formed by spirally winding a conductor wire and a ferrite or the like mounted inside the winding coil. It is composed of a core and electrodes 14a provided at both ends of the ferromagnetic core.

Further, the hybrid integrated circuit 10 can be manufactured, for example, according to the following order. First, a paste-like ferromagnetic material is applied to the insulating substrate 11 by a screen printing method.
After being formed into a predetermined shape on the top, it is fired to form the thick film ferromagnetic layer 12. Next, the soldering lands 13a, 13
b is also formed of paste-like copper in the same order and method as the thick-film ferromagnetic layer 12.

Further, cream-like solder is formed on the soldering lands 13a and 13b by screen printing,
The choke coil 1 is attached to the soldering lands 13a and 13b.
4 is placed, and reflow solder is flown to the electrode 14a of the choke coil 14 for solder connection.

As described above, according to this embodiment, the insulating substrate 1
By forming the thick-film ferromagnetic layer 12 under the choke coil 14 of No. 1, the magnetic flux generated by the choke coil 14 passes through the thick-film ferromagnetic layer 12, and the magnetic flux passing through the air decreases. . Therefore, the magnetic resistance and the leakage magnetic flux are reduced, and the inductance value can be increased.

Further, since the thick film ferromagnetic layer 12 is formed so as to extend to the outside of the choke coil 14, the magnetic flux can easily pass therethrough, and the magnetic resistance and the leakage magnetic flux can be further reduced.

FIG. 2 is a plan view showing a second embodiment of the hybrid integrated circuit according to the present invention. The same parts as those in the first embodiment will be described with the same reference numerals. As shown in FIG. 2, the insulating substrate 11 is formed on the thick-film ferromagnetic layer 12 of this embodiment.
In addition to the portion where the upper choke coil 14 is mounted, fan-shaped projecting portions 12a are formed so as to be sandwiched from both sides of the soldering lands 13a and 13b, respectively.

Therefore, the magnetic flux generated by the choke coil 14 also passes through the fan-shaped overhanging portion 12a in addition to the thick-film ferromagnetic material layer 12, and the magnetic resistance and the leakage magnetic flux are further reduced in this embodiment. You can The rest of the configuration and operation are the same as in the first embodiment, so a description thereof will be omitted.

FIG. 3 is a plan view showing a third embodiment of the hybrid integrated circuit according to the present invention. The same parts as those in the first embodiment will be described with the same reference numerals. As shown in FIG. 3, the thick-film ferromagnetic layer 12 of the present embodiment has a plurality of thin thin-film ferromagnetic layers 12 at predetermined intervals along the inter-electrode direction of the choke coil 14 in the portion where the choke coil 14 is mounted on the insulating substrate 11. It is formed in a band shape.

Therefore, according to this embodiment, the eddy current generated by the current flowing through the choke coil 14 is divided by the thick ferromagnetic layer 12 formed in plural with a predetermined gap, It is possible to reduce eddy current loss. The rest of the configuration and operation are the same as in the first embodiment, so a description thereof will be omitted.

FIG. 4 is a vertical sectional view showing a fourth embodiment of the hybrid integrated circuit according to the present invention. The same parts as those in the first embodiment will be described with the same reference numerals. In this embodiment, a groove 11a is formed in a portion of the insulating substrate 11 where the choke coil 14 is mounted, and the thick film ferromagnetic layer 1 is formed in the groove 11a.
2 is formed.

Therefore, according to the present embodiment, since the thick film ferromagnetic material layer 12 is also formed in the groove 11a, the thickness of the thick film ferromagnetic material layer 12 becomes thicker, and the magnetic resistance and the leakage magnetic flux are reduced. It can be further reduced. The rest of the configuration and operation are the same as in the first embodiment, so a description thereof will be omitted.

The present invention is not limited to the above embodiments, but various modifications can be made. For example, in each of the above-described embodiments, the ferromagnetic material that reduces the magnetic resistance and the leakage magnetic flux is formed as a layer with a thick film. However, the present invention is not limited to this, and a thin film or a plate may be used.

In each of the above embodiments, the thick ferromagnetic layer 1
2 is enlarged to the outside of the choke coil 14, but a ferromagnetic material may be provided on the insulating substrate 11 at least under the choke coil 14.

[0030]

As described above, according to the hybrid integrated circuit of the present invention, since the magnetic material is provided at least under the choke coil on the substrate, the magnetic resistance and the leakage magnetic flux are reduced, and the inductance value is reduced. Will increase. As a result, the quality and function of the hybrid integrated circuit can be significantly improved.

Further, since the magnetic material is enlarged to the outside of the choke coil, or the groove is formed in the substrate under the choke coil and the magnetic material is provided in the groove, the magnetic resistance and the leakage flux are increased. Can be further reduced.

Further, the eddy current loss of the choke coil can be reduced by forming the magnetic material in a plurality of thin strips at predetermined intervals along the direction between the electrodes of the choke coil.

[Brief description of drawings]

1A and 1B are a longitudinal sectional view and a plan view showing a first embodiment of a hybrid integrated circuit according to the present invention.

FIG. 2 is a plan view showing a second embodiment of the hybrid integrated circuit according to the present invention.

FIG. 3 is a plan view showing a third embodiment of the hybrid integrated circuit according to the present invention.

FIG. 4 is a vertical sectional view showing a fourth embodiment of the hybrid integrated circuit according to the present invention.

5A and 5B are a vertical sectional view and a plan view showing a conventional hybrid integrated circuit.

[Explanation of symbols]

 10 Hybrid Integrated Circuit 11 Insulating Substrate 11a Groove 12 Thick Film Ferromagnetic Layer 12a Overhang 13a Soldering Land 13b Soldering Land 14 Choke Coil 14a Electrode 15 Solder

Claims (4)

[Claims] 1. A winding coil in which a conductive wire is spirally wound,
In a hybrid integrated circuit in which a choke coil having a magnetic core mounted inside the winding coil and electrodes provided at both ends of the magnetic core is mounted on a substrate, at least a lower portion of the choke coil on the substrate is provided. A hybrid integrated circuit characterized in that a magnetic material is provided in the. 2. The hybrid integrated circuit according to claim 1, wherein the magnetic body is formed so as to extend to the outside of the choke coil. 3. The hybrid integrated circuit according to claim 1, wherein the magnetic body is formed into a plurality of thin strips at predetermined intervals along the direction between the electrodes of the choke coil. 4. The hybrid integrated circuit according to claim 1, wherein a groove is formed in the substrate below the choke coil, and the magnetic body is provided in the groove.