JPH08124795A - Multilayered capacitor - Google Patents

Abstract

PURPOSE: To provide a multilayered capacitor wherein the mounting density on a circuit board is improved. CONSTITUTION: Two capacitors are formed between conductive films 12, 13 formed on a dielectric sheet 10 and a conductive film 31. Two capacitors are formed between conductive films 22, 23 formed on a dielectric sheet 20 and a conductive film 31.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multilayer capacitor used for high density mounting.

[0002]

2. Description of the Related Art Conventionally, for example, as a countermeasure against high frequency noise in electronic equipment, a multilayer capacitor having one capacitor element built in between each of a plurality of signal lines formed on a circuit board of the electronic equipment and a ground. Are mounted in a large number, and high frequency noise is bypassed to the ground by a large number of these multilayer capacitors, so that malfunction of the electronic device can be prevented. In order to improve the packaging density of the circuit board of such electronic devices, a small number of these multilayer capacitors are used.

[0003]

However, when manufacturing a multilayer capacitor in a small size, in the current manufacturing process, for example, the external dimensions of the multilayer capacitor are 1.0 mm (width) × 0.
When the thickness is 5 mm (depth) or less, it becomes difficult to control the handling property and dimensional accuracy, and the productivity of the multilayer capacitor decreases. Further, when mounting a multilayer capacitor having such an external dimension on a circuit board, it becomes difficult to control the accuracy of the mounting dimension of the multilayer capacitor on the circuit board, and the productivity of the circuit board also decreases. Therefore, it is not easy to mount the multilayer capacitors on the circuit board with high density, which is problematic.

In view of the above circumstances, it is an object of the present invention to provide a multilayer capacitor each time the mounting density of the capacitor on the circuit board is improved.

[0005]

Means for Solving the Problems A multilayer capacitor according to the present invention which achieves the above object is (1) a first conductive film connected to the ground (2) first and second conductive films sandwiching the first conductive film. 2 dielectric sheet (3) of each of the first and second dielectric sheets,
A plurality of second conductive films, which are formed on the surface opposite to the first conductive film side and form a capacitor between the second conductive films, and the second conductive films. It is characterized in that it is provided with a third conductive film which is interposed between and connected to the ground.

[0006]

The multilayer capacitor of the present invention has the above structure.
A plurality of capacitors are formed between the plurality of second conductive films formed on each of the first and second dielectric sheets and the first conductive film. When this multilayer capacitor is mounted on a circuit board, a plurality of capacitors are mounted. For example, in comparison with a case where a plurality of conventional multilayer capacitors are formed, one capacitor is mounted on the circuit board.
The area occupied by the multilayer capacitor can be small. Therefore, the mounting density of the capacitors on the circuit board can be easily improved. Further, when one multilayer capacitor is mounted on the circuit board, a plurality of capacitors are mounted at one time, which reduces mounting time and improves the productivity of the circuit board.

Further, in the multilayer capacitor of the present invention, since the third conductive film connected to the ground is arranged between the second conductive films forming the capacitors, crosstalk between the capacitors is also prevented. It

[0008]

Embodiments of the present invention will be described below. FIG. 1 is a diagram in which dielectric sheets of a four-element multilayer capacitor as an example of the multilayer capacitor of the present invention are arranged in the stacking order. Five dielectric sheets 10, 20, 3 shown in FIG.
Each of 0, 40, and 50 is a rectangular dielectric sheet having the same shape and size.

The dielectric sheet 10 is electrically insulated from each other and divided into three parts. At the central portion of the dielectric sheet 10, the end portions 11a and 11b are extended to two sides in the longitudinal direction of the dielectric sheet 10.
The conductive film 11 having is formed. This conductive film 11
Corresponds to the third conductive film referred to in the present invention and is connected to the ground. Conductive films 12 and 13 are formed on both sides of the conductive film 11. The conductive films 12 and 13 have ends 12a and 13a at corners of the dielectric sheet 10 that face each other. These conductive films 12 and 13 correspond to the second conductive film according to the present invention.

The dielectric sheet 20 includes the dielectric sheet 10
The conductive film 2 at positions corresponding to the conductive films 11, 12, and 13 of
1, 22, 23 are formed respectively. Conductive film 21
Corresponds to the third conductive film according to the present invention, and the end portions 21a and 21b extended to two sides in the longitudinal direction of the dielectric sheet 20.
have. The conductive film 21 is connected to the ground. In addition, the conductive films 22 and 23 correspond to the second conductive film according to the present invention, and the end portions 22 at the corners of the dielectric sheet 20 corresponding to the corners different from the corners at which the end portions 12a and 13a are formed.
a and 23a respectively.

The dielectric sheet 30 includes the dielectric sheet 10
The conductive film 31 having a size including the conductive films 11, 12, and 13 is formed. The conductive film 31 is the conductive film 1
It has end portions 31a and 31b having the same width dimension as that of No. 1. Further, the conductive film 31 is connected to the ground. The conductive film 31 corresponds to the first conductive film according to the present invention.

The dielectric sheets 40 and 50 are dielectric sheets having no conductive film formed thereon. 2 is an external perspective view of a four-element multilayer capacitor in which the dielectric sheets shown in FIG. 1 are laminated on each other and electrodes are formed, and FIG. 3 is an equivalent circuit diagram of the four-element multilayer capacitor. The four-element multilayer capacitor shown in FIG. 2 has the dielectric sheet 10, 20, 3 shown in FIG.
In contrast to 0, 40 and 50, the end portion 11a of the conductive film 11
The end portion 31a of the conductive film 30 and the end portion 21a of the conductive film 21 are connected by the electrode 63. In addition, the conductive film 1
The end portion 11b of No. 1 and the end portion 31b of the conductive film 30 are connected to the end portion 21b of the conductive film 21 by an electrode 73.
Further, the end portion 12a of the conductive film 12 and the conductive film 13a of the conductive film 13 are connected to the electrodes 61 and 62, respectively.
Of the electrodes 71 and 7
2 are connected to each.

Contrasting such a four-element multilayer capacitor with the equivalent circuit shown in FIG. 3, the conductive film 12 and the conductive film 1 are compared.
The capacitor 81 and the capacitor 82 are formed from 3 and the conductive film 31. In addition, the conductive film 22 and the conductive film 2
3 and the conductive film 31 form a capacitor 83 and a capacitor 84. The conductive films 11 and 21 are connected to the conductive film 31 and have a role of preventing crosstalk.

In this embodiment, since four capacitors 81, 82, 83, 84 are formed on one multilayer capacitor, four multilayer capacitors each having one capacitor element are mounted on the circuit board. As compared with the case where the mounting is performed, the mounting space for three multilayer capacitors is not required, and the mounting density of the capacitors on the circuit board is improved accordingly.

[0015]

As described above, according to the present invention,
Since a plurality of capacitors are formed on one multilayer capacitor, mounting this multilayer capacitor on a circuit board can improve the mounting density of the capacitors on the circuit board and reduce the mounting cost. .

[Brief description of drawings]

FIG. 1 is a diagram showing an example of a multilayer capacitor according to an embodiment of the present invention.
It is the figure which arranged the dielectric sheet of the element multilayer capacitor in order of lamination.

FIG. 2 is an external perspective view of a four-element laminated capacitor in which the dielectric sheets shown in FIG. 1 are laminated with each other and electrodes are formed.

FIG. 3 is an equivalent circuit diagram of a 4-element multilayer capacitor.

[Explanation of symbols]

10, 20, 30, 40, 50 Dielectric sheet 11, 12, 13, 21, 22, 23, 31 Conductive film 11a, 11b, 12a, 13a, 21a, 21b, 2
2a, 23a, 31a, 31b Ends 61, 62, 63, 71, 72, 73 Electrodes 81, 82, 83, 84 Capacitors

Claims (1)

[Claims] 1. A first conductive film connected to the ground, first and second dielectric sheets sandwiching the first conductive film, and each of the first and second dielectric sheets, The first
A plurality of second conductive films, each of which is formed on a surface opposite to the conductive film side, forming a capacitor between the first conductive film and the second conductive films. A multilayer capacitor comprising: an intervening third conductive film connected to the ground.