JPH1012491A - 4-terminal multilayer capacitor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a 4-terminal multilayer capacitor which exhibits excellent attenuation characteristics over a wide frequency band. SOLUTION: A 4-terminal multilayer capacitor 1 is composed of a dielectric sheet 2 which has an inner inductor electrode 3 which connects an input outer electrode and an output outer electrode electrically to each other, dielectric sheet 2 which have inner capacitor electrodes 5 connected electrically to the input outer electrode and inner capacitor electrodes 6 electrically connected to the output outer electrode on their surfaces, dielectric sheets 2 which have inner grounding electrodes 4 connected to a grounding outer electrode on their surfaces, etc., and those dielectric sheets 2, etc., are piled up in layers and backed integrally.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a four-terminal multilayer capacitor, and more particularly to a four-terminal multilayer capacitor used for removing noise in electronic equipment and the like.

[0002]

2. Description of the Related Art A two-terminal type multilayer capacitor and a four-terminal type multilayer capacitor have been used for removing noise from electronic equipment and the like. In particular, as shown in FIG. 8, the four-terminal multilayer capacitor includes a dielectric sheet 52 having an internal ground electrode 53 on its surface, a dielectric sheet 52 having an internal capacitor electrode 54 on its surface, and a dielectric material for a protective layer. It is composed of a sheet 52 and the like.

Each of the dielectric sheets 52 is stacked and integrally fired to form a capacitor 51 shown in FIG.
Is obtained. Input external electrodes 56 and output external electrodes 57 are formed on both ends of the capacitor 51, and ground external electrodes 58 and 59 are formed on the front and rear side surfaces. FIG. 10 is an electrical equivalent circuit diagram of the capacitor 51.
The resonance frequency of the four-terminal multilayer capacitor 51 is generally higher than that of the two-terminal multilayer capacitor, and high attenuation can be obtained in a high frequency range.

[0004]

However, in the conventional four-terminal multilayer capacitor 51, although high attenuation is obtained in a high frequency range, the attenuation is smaller than the two-terminal multilayer capacitor near the resonance frequency of the two-terminal multilayer capacitor. Was inferior. Accordingly, an object of the present invention is to provide a four-terminal multilayer capacitor having excellent attenuation characteristics even in the resonance frequency range of a two-terminal multilayer capacitor while ensuring high attenuation in a high frequency range.

[0005]

In order to achieve the above object, a four-terminal multilayer capacitor according to the present invention comprises: (a) a first internal capacitor electrode electrically connected to an input external electrode; b) a second electrically connected output external electrode
(C) an internal ground electrode electrically connected to the two ground external electrodes and forming a capacitance between the first and second internal capacitor electrodes, respectively; An internal inductor electrode electrically connected between the input external electrode and the output external electrode is provided.

[0006]

The resonance frequency is lower than the resonance frequency of the conventional four-terminal multilayer capacitor due to the inductance of the internal inductor electrode. The width of the high-attenuation frequency band is widened by the two capacitances formed between the first and second internal capacitor electrodes and the internal ground electrode.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a four-terminal multilayer capacitor according to the present invention will be described with reference to the accompanying drawings. In each embodiment, the same components and the same portions are denoted by the same reference numerals. [First Embodiment, FIGS. 1 to 4] As shown in FIG. 1, a four-terminal multilayer capacitor 1 has a dielectric sheet 2 provided with an internal inductor electrode 3 on its surface, and an internal ground electrode 4 provided on its surface. It is composed of a dielectric sheet 2, a dielectric sheet 2 provided with internal capacitor electrodes 5 and 6 on its surface, a dielectric sheet 2 as a protective layer, and the like. Each dielectric sheet 2 is made of, for example, a ceramic material.

The internal inductor electrode 3 has a meandering shape, and both ends 3a and 3b are exposed at the left and right edges of the sheet 2, respectively. The internal ground electrode 4 is formed in a wide area on the sheet 2, and ends 4 a and 4 b are exposed at front and rear edges of the sheet 2, respectively. The internal capacitor electrodes 5 and 6 are formed at the leftward position and the rightward position of the sheet 2, and have one end portions 5a and 5a, respectively.
6a are exposed at the left and right edges of the sheet 2. Electrodes 3 ~
Reference numeral 6 is made of Ag, Ag-Pd, Ni, or the like, and is formed by a method such as printing, sputtering, or vacuum evaporation.

The dielectric sheets 2 are stacked as shown in FIG. 1 and then fired to form a laminate. As shown in FIG. 2, an input external electrode 10 and an output external electrode 11 are formed on both left and right ends of the laminate, and ground external electrodes 12 and 13 are formed on the front and rear side surfaces. The input external electrode 10 is electrically connected to the end 3a of the internal inductor electrode 3 and the end 5a of the internal capacitor electrode 5, and the output external electrode 11 is connected to the end 3b of the internal inductor electrode 3 and the end of the internal capacitor electrode 6. 6a, and the ground external electrodes 12, 13 are electrically connected to the ends 4a, 4b of the internal ground electrode 4, respectively.

As shown in FIG. 3, the four-terminal multilayer capacitor 1 having the above-described structure is different from the conventional one capacitor in two capacitors, that is, the capacitor C1 including the internal capacitor electrode 5 and the internal ground electrode 4 and the internal capacitor. The capacitor is separated into a capacitor C2 including a capacitor electrode 6 and an internal ground electrode 4, and both capacitors C1 and C2 are electrically connected by an internal inductor electrode 3.

FIG. 4 is a graph showing the results of measuring the attenuation characteristics of the four-terminal multilayer capacitor 1 having a capacitance of 0.15 μF (see the solid line 21). FIG. 4 also shows, for comparison, the attenuation characteristics of a conventional two-terminal multilayer capacitor having the same capacitance (see dotted line 22) and the attenuation characteristics of a conventional four-terminal multilayer capacitor (see dotted line 23). I have. Due to the inductance of the internal inductor electrode 3, the resonance frequency of the capacitor 1 of the first embodiment is lower than the resonance frequency of the conventional four-terminal multilayer capacitor. The capacitors C1 and C2 widen the frequency band of high attenuation.

[Second Embodiment, FIGS. 5 to 7] As shown in FIG. 5, a four-terminal multilayer capacitor 31 of a second embodiment has an internal inductor electrode 32 and an internal capacitor electrode 33,
Except for 34, it is the same as the capacitor 1 of the first embodiment. The internal inductor electrode 32 has a meandering portion 32a,
The two ends 32d and 32e are exposed to the left and right edges of the sheet 2, respectively. The internal capacitor electrode 33 is electrically connected to the meandering portions 32a and 32b, and the internal capacitor electrode 34 is connected to the meandering portions 32b and 32b.
c is electrically connected.

Each dielectric sheet 2 is stacked as shown in FIG. 5 and then fired to form a laminate. As shown in FIG. 6, an input external electrode 36 and an output external electrode 37 are formed on both left and right ends of the laminate, and ground external electrodes 38 and 39 are formed on the side surfaces on the near side and the far side. The input external electrode 36 is electrically connected to the end 32d of the internal inductor electrode 32 and the end 5a of the internal capacitor electrode 5, and the output external electrode 37 is connected to the end 32e of the internal inductor electrode 32 and the end of the internal capacitor electrode 6. 6a
The ground external electrodes 38 and 39 are electrically connected to the ends 4a and 4b of the internal ground electrode 4, respectively.

As shown in FIG. 7, the four-terminal type multilayer capacitor 31 having the above-described structure is different from the conventional one capacitor in two capacitors, that is, the internal capacitor electrode 5.
And a capacitor C1 composed of the internal ground electrode 4 and a capacitor C2 composed of the internal capacitor electrode 6 and the internal ground electrode 4. Between the capacitors C1 and C2, an inductance composed of the internal inductor electrode 32 and internal capacitor electrodes 33, 34, 4 are provided. Capacitors C3 and C
4 are electrically connected by the LC circuit configured. The four-terminal multilayer capacitor 31 has the effect of shifting the resonance frequency to a lower frequency side than the capacitor 1 of the first embodiment.

[Other Embodiments] The four-terminal multilayer capacitor according to the present invention is not limited to the above embodiment, but can be variously modified within the scope of the gist. In the embodiment, in order to suppress the stray capacitance generated between the internal inductor electrode and the internal ground electrode, the spacer dielectric sheet is formed of a dielectric sheet provided with the internal inductor electrode and a dielectric sheet provided with the internal ground electrode. It may be inserted between them. Further, a structure in which a pair of the internal inductor electrode and the internal ground electrode are arranged at an arbitrary position in the laminating direction may be employed to provide a symmetrical arrangement of the electrodes or to adjust the inductance component.

Further, the above embodiment has been described by taking the case of individual products as an example. However, in the case of mass production, it is manufactured on a mother board provided with a plurality of capacitors, and cut into a desired size to obtain a product. be able to. In the above embodiment, the sheets are stacked and then integrally sintered, but the present invention is not necessarily limited to this. The sheet may be a sheet sintered in advance. Alternatively, a capacitor having a laminated structure may be obtained by sequentially applying a paste-like dielectric material or a conductive material by a method such as printing, drying, and applying again.

[0017]

As is apparent from the above description, according to the present invention, since the internal inductor electrode, the first and second internal capacitor electrodes and the internal ground electrode are provided, two capacitances and an internal inductor are provided. Due to the inductance of the electrodes, the resonance frequency can be lower than that of the conventional four-terminal multilayer capacitor while maintaining the same attenuation in the high frequency range. As a result, a four-terminal multilayer capacitor having excellent attenuation characteristics in a wide frequency band can be obtained.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a first embodiment of a four-terminal multilayer capacitor according to the present invention.

FIG. 2 is a perspective view showing an appearance of the four-terminal multilayer capacitor shown in FIG.

3 is an electrical equivalent circuit diagram of the four-terminal multilayer capacitor shown in FIG.

FIG. 4 is a graph showing attenuation characteristics of the four-terminal multilayer capacitor shown in FIG. 2;

FIG. 5 is an exploded perspective view showing a second embodiment of the four-terminal multilayer capacitor according to the present invention.

FIG. 6 is an exemplary perspective view showing the appearance of the four-terminal multilayer capacitor shown in FIG. 5;

FIG. 7 is an electric equivalent circuit diagram of the four-terminal multilayer capacitor shown in FIG. 6;

FIG. 8 is an exploded perspective view of a conventional four-terminal multilayer capacitor.

FIG. 9 is a perspective view showing an appearance of the four-terminal multilayer capacitor shown in FIG. 8;

10 is an electric equivalent circuit diagram of the four-terminal multilayer capacitor shown in FIG.

[Explanation of symbols]

 1, 31 4-terminal multilayer capacitor 3, 33 Internal inductor electrode 4, Internal ground electrode 5, 6 Internal capacitor electrode 10, 36 Input external electrode 11, 37 Output external electrode 12, 13, 38, 39 Ground external electrode

Claims (1)

[Claims] 1. A four-terminal multilayer capacitor having an input external electrode, an output external electrode and two ground external electrodes, wherein: a first internal capacitor electrode electrically connected to the input external electrode; A second internal capacitor electrode electrically connected to the electrode; and a second internal capacitor electrode electrically connected to the two ground external electrodes to form capacitance between the first and second internal capacitor electrodes, respectively. A four-terminal multilayer capacitor comprising: an internal ground electrode; and an internal inductor electrode that electrically connects the input external electrode and the output external electrode.