JPH0529114A - Surge absorber - Google Patents

Abstract

PURPOSE:To remove current surge as well as voltage surge and to prevent the transmission of a signal from being interfered. CONSTITUTION:An input electrode 22 and an output electrode 23 are provided separately on the surface of a varistor substrate 21, and a resistor element 24 is connected between both electrodes 22 and 23. A varistor element is made of the input electrode and an earth electrode 22 by providing the earth electrode 23 in the position opposed with the input electrode 22 through the varistor substrate 21 on the back of the varistor substrate 21, and the voltage surge and the current surge can be removed by it and the resistor element 24, and the signal is not weakened by the capacitance of the varistor element, and the signal transmission is not interfered.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surge absorbing component, and more specifically, it can suppress both an external voltage surge and a current surge and does not hinder normal signal transmission. The present invention relates to surge absorbing parts.

[0002]

2. Description of the Related Art As a measure against an external surge entering a signal line, when a general varistor element 1 is attached to a signal line AA 'as shown in FIG. 7, the voltage surge V is suppressed by the varistor element 1. However, there is a drawback that the current surge I cannot be suppressed.

Therefore, in order to suppress not only the voltage surge but also the current surge, a three-terminal surge absorbing component with a built-in resistor has been proposed as shown in FIG.

In this surge absorbing component, as shown in FIG. 8 (a), the input electrode 3 and the output electrode 4 are formed on the surface of the varistor substrate 2.
And the resistance element 5 is mounted between the input electrode 3 and the output electrode 4, and the input electrode 3 and the output electrode 4 and the varistor 4 are provided on the back side of the varistor substrate 2 as shown in FIG. 8 (b). A ground electrode 6 having a size facing each other across the substrate 2 is provided, and the input electrode 3, the output electrode 4 and the ground electrode 6 are provided.
The lead terminals 7, 8 and 9 are connected to each of the above.

[0005]

By the way, in the above-mentioned conventional surge absorbing component, the ground electrode 6 is provided so as to face both the input electrode 3 and the output electrode 4, and therefore, the equivalent circuit of FIG. 9 is shown. Thus, there are two varistor elements 10 and 11 sandwiching the resistance element 5, whereby the capacitance C ₂ of the varistor element 11 on the output electrode 4 side and the resistance value R of the resistance element 5 are Depending on the time constant,
As shown in FIG. 10, there is a problem that the signal waveform desired to be transmitted through the signal line is weakened or cannot be transmitted.

In order to solve the above problems, the present invention provides a surge absorbing component that can remove both voltage surge and current surge and does not hinder signal transmission. To aim.

[0007]

In order to solve the above problems, the present invention provides a plurality of divided electrodes and a resistance element located between the divided electrodes on one side of a varistor substrate. A structure is provided in which only one electrode of the divided electrodes and an electrode facing each other across the varistor substrate are provided on the other surface side of the varistor substrate.

[0008]

A plurality of divided electrodes and a resistance element located between the divided electrodes are provided on one surface side of the varistor substrate, and an electrode opposed to only one electrode is provided on the other surface side of the varistor substrate. Therefore, it becomes a surge absorbing component that has one varistor element and resistance element formed by the opposing electrodes, can absorb both voltage surge and current surge, and the varistor element generates capacitance on the output electrode side connected to the resistance element. Therefore, it does not hinder normal signal transmission.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS.

In the first embodiment shown in FIG.
As shown in (a), the input electrode 2 is formed on the surface of the varistor substrate 21.
2 and the output electrode 23 are separately provided on both sides, and a resistance element 24 is provided between the divided input electrode 22 and output electrode 23. The input electrode 22 has an input terminal 25 and the output electrode 23 has an output terminal 26. Are connected to each other.

The back surface of the varistor substrate 21 is shown in FIG.
As described above, the ground electrode 27 is provided so as to face the input electrode 22 by sandwiching the varistor substrate 21.
A ground terminal 28 is connected to 7.

The above-mentioned output electrode 23 is used only for connecting the output terminal 26 and the resistance element 24, the electrode area thereof is formed smaller than that of the input electrode 22, and the ground electrode 27 is connected to the input electrode. It is formed in such a size that a portion for connecting the ground terminal 28 is provided in an area facing the electrode 22, and does not face the output electrode 23.

In the surge absorbing component having the above structure, the varistor substrate 21 is sandwiched between the input electrode 22 and the ground electrode 27.
Face each other and the output electrodes 23 are independent of each other,
As shown in the equivalent circuit of FIG. 2, the structure has one varistor element 29 formed by the input electrode 22 and the ground electrode 27, and the resistance element 24.

Next, in the second embodiment shown in FIGS. 3A and 3B, the area of the ground electrode 27 is made smaller than that of the first embodiment, and the ground terminal 28 is brought closer to the input terminal 25. It was done like this.

By doing so, the ground electrode 2
7 can be increased to reduce the stray capacitance that tends to occur between the earth electrode 27 and the output electrode 23, and the gap between the terminals 25 and 28 and the gap between the terminals 26 and 28 can be made different from each other. Directionality can be generated, and incorrect connection can be prevented.

In the third embodiment shown in FIGS. 4 (a) and 4 (b), an extension 22a is provided on the upper portion of the input electrode 22, and the extension 2
A resistance element 24 is provided between the output electrode 23 and the extension portion 22a which are separately provided at a position below 2a.

In the fourth embodiment shown in FIGS. 5 (a) and 5 (b), the input electrode 22 is provided with an extension portion 22a, and a chip resistance element 24a is connected to this extension portion 22a, and a chip resistance is used as an output electrode. This is a substitute for the external electrode 24b of the element 24a, and since there is no output electrode on the surface of the varistor substrate 21, there is no stray capacitance between the ground terminal 28 and the output terminal 26.

In the fifth embodiment shown in FIGS. 6 (a) and 6 (b), a resistor element 24c formed by paste-applying and baking a resistor material on the surface of the varistor substrate 21 is provided. One end of the resistance element 24c overlaps the input electrode 22, and the other end of the resistance element 24c is provided with an output electrode 23 also formed by coating, baking, etc., and an output terminal 26 is connected to the output electrode 23. There is.

In the second to fifth embodiments, the equivalent circuit shown in FIG. 3 is obtained, and in any of the embodiments, the composition of the varistor substrate 21 used, the material and forming method of each electrode, the resistance element are used. The type and the forming method of the may be freely selected.

The surge absorbing component of the present invention has the above-mentioned structure, and one varistor element is provided on the varistor substrate.
It has a structure with a resistance element, removes both voltage surge and current surge to protect the internal circuit, and it can be used for normal signal transmission without weakening the signal waveform to be transmitted due to the capacitance of the varistor element. It does not hinder.

[0021]

As described above, according to the present invention, it is possible to remove both the voltage surge and the current surge that enter the signal line, and at the same time, the signal transmission is not hindered.

[Brief description of drawings]

FIG. 1A is a front view showing a first embodiment of a surge absorbing component according to the present invention, and FIG. 1B is a rear view thereof.

FIG. 2 is an equivalent circuit diagram of the first embodiment of the surge absorbing component according to the present invention.

3 (a) is a front view showing a second embodiment of the surge absorbing component according to the present invention, and FIG. 3 (b) is a rear view thereof.

FIG. 4 (a) is a front view showing a third embodiment of the surge absorbing component according to the present invention, and FIG. 4 (b) is a rear view thereof.

5A is a front view showing a fourth embodiment of a surge absorbing component according to the present invention, and FIG. 5B is a rear view thereof.

6 (a) is a front view showing a fifth embodiment of the surge absorbing component according to the present invention, and FIG. 6 (b) is a rear view thereof.

FIG. 7 is a circuit diagram for performing conventional voltage surge absorption.

FIG. 8 (a) is a front view showing a conventional surge absorbing component,
(b) is the rear view.

FIG. 9 is an equivalent circuit diagram of a conventional surge absorbing component.

FIG. 10 is an explanatory diagram showing changes in signal waveform.

[Explanation of symbols]

 21 Insulating Substrate 22 Input Electrode 23 Output Electrode 24 Resistance Element 25 Input Terminal 26 Output Terminal 27 Ground Electrode 28 Ground Terminal

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masanori Ueyama 2 26-10 Tenjin Tenjin, Nagaokakyo, Kyoto Prefecture Murata Manufacturing Co., Ltd.

Claims (1)

Claim: What is claimed is: 1. A plurality of divided electrodes and a resistance element located between the divided electrodes are provided on one surface side of the varistor substrate, and are divided on the other surface side of the varistor substrate. A surge absorbing component that has only one electrode and the opposite electrode sandwiching the varistor substrate.