JP2001110612A - Resistor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resistor, in which imperfect soldering is not generated when it is mounted on a printed board, and soldering property is superior. SOLUTION: This resistor is provided with a plurality of individual electrode layers 12a-12h, which are formed on the side part of a substrate 11 so as to face each other, a common electrode layer 13 which is connected electrically with one from among the individual electrodes layers 12a-12h, positioned between the facing individual electrodes 12a-12h, and formed on the upper surface of the substrate 11, a plurality of resistance elements 14a-14e which are formed to connect electrically the individual electrode layers 12a-12h with the common electrode layer 13, and a plating layer which is formed on surfaces of the individual electrode layers 12a-12h and the common electrode layer 13 and has an outermost layer composed of solder. The DC resistance values of the resistance elements 14a-14b are at least 10 kΩ.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resistor used in various electronic circuits.

[0002]

2. Description of the Related Art As a conventional resistor of this type, a resistor described in Japanese Patent Application Laid-Open No. 8-186012 is known.

FIG. 4 is a plan view of a conventional chip-type network resistor (hereinafter, referred to as a resistor).

In FIG. 4, reference numeral 1 denotes an insulating substrate.
Reference numeral 2 denotes a common electrode layer provided on the upper surface of the substrate 1 and made of an alloy of silver and palladium. Reference numerals 3a to 3h denote a plurality of individual electrode layers provided on the side surface of the substrate 1 and made of an alloy of silver and palladium. 4a to 4e are a plurality of resistance layers electrically connected to the common electrode layer 2 and the plurality of individual electrode layers 3a to 3h. 2a is a main body of the common electrode layer 2, and the main body 2a constitutes the common electrode layer 2 together with the two common electrode terminals 2b. It is provided up to the lower surface side of the substrate 1 beyond. Reference numeral 5 denotes a protective layer made of an insulator provided on the upper surface of the substrate 1 so as to cover at least the plurality of resistance layers 4a to 4e.

On the upper surface of such a substrate 1, a common electrode layer 2
And a plurality of individual electrode layers 3a to 3h,
When a nickel plating layer and a solder plating layer are formed by a barrel plating method on a resistor provided with a plurality of resistance layers 4a to 4e respectively interposed between the common electrode layer 2 and a. Of the individual electrode layers 3a to 3h connected to the relatively large resistance layers 4a to 4e, such that the current flowing therethrough is smaller than that of the common electrode layer 2, so that the individual electrode layers 3a to 3h Is difficult to form a nickel plating layer and a solder plating layer on the common electrode layer 2. It is extremely thicker than the thickness of the plating layer. Conventionally, in order to prevent this, a stir plate is provided inside the plating barrel, and plating is performed while sufficiently stirring with this stir plate, so that the nickel plating layer and the solder plating layer of the common electrode layer 2 are formed. The layer thickness was set to be about three times or less the thickness of the nickel plating layer and the solder plating layer in the plurality of individual electrode layers 3a to 3h.

[0006]

However, according to the above-mentioned prior art, for example, the resistance layer 4 having a DC resistance of 10 KΩ is used.
In the case of a resistor having a to 4e, the individual electrode layers 3a to 3h
On the other hand, the common electrode layer 2 is 2.33 times the solder plating layer,
The nickel plating layer has a thickness ratio of 2.35 times. Thereby, for example, when the thickness of each of the individual electrode layers 3a to 3h is 2 μm for each of the solder plating layer and the nickel plating layer, the total thickness becomes 4 μm, and the common electrode layer 2 has two 3. Thickness of the solder plating layer
Since it is 66 μm and 4.70 μm for the nickel plating layer, the total is 9.36 μm, whereby a difference of about 5 μm between the thickness of the individual electrode layer 2 and the thickness of the individual electrode layers 3 a to 3 h is obtained. Will occur. Also, in the barrel plating method, a variation in plating film thickness occurs.
Actually, the individual electrode layers 3a to 3h have a layer thickness of 2 μm or more, and as a result, the difference in the layer thickness between the individual electrode layers 3a to 3h and the common electrode layer 2 is increasing. is there.

Here, a mounting state when a conventional resistor is mounted on a printed circuit board or the like by soldering will be described.

FIG. 5 is a schematic view of a state where a conventional resistor is soldered, as viewed from the side. The resistor 6 is mounted at a predetermined position on a printed circuit board 7. When the common electrode terminal portion 2b and the individual electrode layers 3e to 3h of the common electrode layer 2 and the lands (not shown) of the printed circuit board 7 are soldered using the solder pastes 8a to 8e on the lands, the common The electrode terminal portion 2b has a layer thickness of individual electrode layers 3e to 3e.
If the thickness is larger than the layer thickness h, there is a difference in the layer thickness. When mounted in such an inclined state, the individual electrode layers 3g and 3h are not connected to the solder pastes 8d and 8e on the lands,
There is a problem that the soldering may be defective.

An object of the present invention is to solve the above-mentioned conventional problems and to provide a resistor excellent in solderability without causing poor soldering even when mounted on a printed circuit board. It is.

[0010]

In order to achieve the above object, a resistor according to the present invention comprises a substrate, a plurality of individual electrode layers provided so as to face side portions of the substrate, and the individual electrode layer. And a common electrode layer provided on the upper surface of the substrate and located between the plurality of opposed individual electrode layers, and the plurality of individual electrode layers and the common electrode layer. A plurality of resistance elements provided so as to be electrically connected, and a plating layer provided on the surface of the plurality of individual electrode layers and the common electrode layer and having an outermost layer made of solder, as the plurality of resistance elements, DC resistance value is 10KΩ
According to this configuration, a resistor excellent in solderability can be provided without causing soldering failure even when mounted on a printed circuit board. is there.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention is directed to a substrate, a plurality of individual electrode layers provided so as to face side portions of the substrate, and one of the individual electrode layers. And a common electrode layer provided on the upper surface of the substrate and located between the opposed plurality of individual electrode layers, and electrically connecting the plurality of individual electrode layers and the common electrode layer. A plurality of resistive elements provided so that the outermost layer is provided on the surface of the plurality of individual electrode layers and the common electrode layer, and a plating layer made of solder is provided. According to this configuration, a resistance element provided to electrically connect a plurality of individual electrode layers and a common electrode layer has a DC resistance value of 47 KΩ or more according to the related art. 10K smaller than that of Since a resistance element of Ω or more is used, current flows more easily to the multiple individual electrode layers, and as a result, the outermost layer formed on the surface of the multiple individual electrode layers also forms a plating layer made of solder Therefore, the thickness of the common electrode layer including the plating layer whose outermost layer is made of solder does not become extremely thick as in the related art. Since the difference in thickness is small, soldering failure does not occur even when this resistor is mounted on a printed circuit board, and it has the effect of providing a resistor with excellent solderability. is there.

According to a second aspect of the present invention, there is provided a substrate, a plurality of individual electrode layers provided so as to face a side portion of the substrate and extend from the upper surface of the substrate to the rear surface via the side surface; While being electrically connected to one of the layers, it is provided on the upper surface of the substrate so as to be located between the plurality of opposing individual electrode layers, and further has its end portion extending from the upper surface of the substrate to the rear surface via the side surface. A plurality of resistance elements provided so as to electrically connect the plurality of individual electrode layers and the common electrode layer, and a plurality of resistance elements provided on the surfaces of the plurality of individual electrode layers and the common electrode layer. The outermost layer provided is provided with a plating layer made of solder, and a thick film layer is separately formed on a plurality of individual electrode layers located on the back surface side of the substrate. According to this configuration, on the back surface side of the substrate, Separate thick layers on multiple individual electrode layers The thickness difference between the common electrode layer and the plurality of individual electrode layers can be reduced because the layers are formed and the layer thickness is increased in advance, so that this resistor can be mounted on the printed circuit board on the back side. In this case, the soldering resistance does not occur, and an effect of providing a resistor excellent in solderability can be provided.

Hereinafter, a chip type network resistor (hereinafter, referred to as a resistor) according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a plan view of a resistor according to an embodiment of the present invention.

In FIG. 1, reference numeral 11 denotes an insulating substrate. Reference numerals 12a to 12h denote a plurality of individual electrode layers made of an alloy of silver and palladium provided so as to face the side of the substrate 11. 13 is a plurality of individual electrode layers 12a to 12h
And a common electrode layer provided on the upper surface of the substrate 11 and located between the plurality of opposing individual electrode layers 12a to 12h. 14a-1
4e denotes a plurality of individual electrode layers 12a to 12h and a common electrode layer 1
3 and a plurality of resistive elements having a DC resistance value of 10 KΩ or more. Reference numeral 15 denotes a protective layer made of an insulator provided on the upper surface of the substrate 11 so as to cover at least the plurality of resistance elements 14a to 14e.

The plurality of individual electrode layers 12a to 12h
Further, a plating layer (not shown) whose outermost layer is made of solder is provided on the surface of the common electrode layer 13, and the thickness of the plurality of individual electrode layers 12 a to 12 h including this plating layer is the same as that of the common layer including the plating layer. The thickness of the electrode layer 13 is larger than that of the electrode layer 13. On the substrate 11, a common electrode layer 13, a plurality of individual electrode layers 12a to 12h, and a plurality of resistance elements 14a to 14h.
14e are formed. The common electrode layer 13 includes one common electrode layer main body 13 a and two common electrode layer terminal portions 1.
3b and 13c. The common electrode layer main body 13a of the common electrode layer 13 is located at the center in the width direction of the substrate 11, and extends to near both ends thereof along the longitudinal direction of the substrate 11. One of the two common electrode layer terminal portions 13b and 13c in the common electrode layer 13 is formed integrally with the common electrode layer main portion 13a, and the one common electrode layer terminal portion 13b is formed integrally with the common electrode layer main portion 13a. 13a extends from one end to one side surface along the longitudinal direction of the substrate 11, and further extends beyond the side surface to the back surface side. The other common electrode layer terminal portion 13c has one end portion overlapping the other end portion of the common electrode layer main body portion 13a, and the other end portion extends to the other side surface along the longitudinal direction of the substrate 11, and further has the side surface. And extends to the back side. In addition, among the plurality of individual electrode layers 12a to 12h, the individual electrode layers 12a to 12h
12d is arranged at a predetermined interval in the longitudinal direction of the substrate 11 and in parallel with the other common electrode layer terminal 13c, and one end thereof faces the common electrode layer main body 13a of the common electrode layer 13 with a predetermined interval. The other end extends to the other side surface along the longitudinal direction of the substrate 11, and further extends beyond the side surface to the back surface side. Among the plurality of individual electrode layers 12a to 12h, the individual electrode layers 12e to 12h are arranged at predetermined intervals in the longitudinal direction of the substrate 11 and in parallel with one common electrode layer terminal portion 13b, and one end portion is shared. The electrode layer 13 faces the common electrode layer main body 13 a at a predetermined interval, and the other end extends to one side surface along the longitudinal direction of the substrate 11, and further extends beyond the side surface to the back surface side. That is, the individual electrode layer 12a and one common electrode layer terminal portion 13b, the individual electrode layer 12b and the individual electrode layer 12e, the individual electrode layer 12c and the individual electrode layer 12f, the individual electrode layer 12d and the individual electrode layer 12g,
The other common electrode layer terminal portion 13c and the individual electrode layer 12h are respectively arranged on a straight line. The resistance element 14a has one end overlapping one end of the common electrode layer main body 13a and the other end overlapping one end of the individual electrode layer 12a. The resistance elements 14b, 14c, 14d
One end overlaps one end of the individual electrode layers 12e, 12f, 12g, and the other end overlaps the individual electrode layers 12b, 12c, 12c.
It overlaps one end of 12d. That is, the central portions of the resistance elements 14b, 14c, and 14d are connected to the common electrode layer main body 1
3a. Further, one end of the resistance element 14e overlaps one end of the individual electrode layer 12h, and the other end overlaps the other end of the common electrode layer main body 13a.

The above-mentioned one common electrode layer terminal portion 13b
Extends from the upper surface of the substrate 11 to the side surface, and further extends beyond the side surface to the back surface side.
As shown in FIG. 1A, a glaze-based thick film layer 21 made of an alloy of silver and palladium formed on the lower surface of the substrate 11.
And a nickel layer 22 plated on the thick film layer 21
And a solder layer 23 which is an alloy of tin and lead plated on the nickel layer 22. This configuration is the same for the other common electrode layer terminal portion 13c. Further, the plurality of individual electrode layers 12a to 12h
Extends from the upper surface of the substrate 11 to the side surface, and further extends beyond the side surface to the back surface side.
As shown in (b), a glaze-based thick film layer 21 made of an alloy of silver and palladium formed on the lower surface of the substrate 11.
And a thick film layer 24 made of a conductive resin containing silver and formed on the thick film layer 21 with a layer thickness of about 5 μm, and plated on the thick film layer 24 made of this resin. And a solder layer 23 which is an alloy of tin and lead plated on the nickel layer 22. This configuration is the same for the other individual electrode layers 12b to 12h. The thickness of the thick film layer 24 made of the conductive resin is 5 μm.

The two common electrode layer terminals 13b,
The thickness of the solder layer 23 in 13c is 2.33 times the thickness of the solder layer 23 in the plurality of individual electrode layers 12a to 12h, and the thickness of the nickel layer 22 in the two common electrode layer terminal portions 13b and 13c is , A plurality of individual electrode layers 12a
The thickness is 2.35 times the layer thickness of the nickel layer 22 in the range from 12 to 12 h.

In the above-described embodiment of the present invention, the plurality of individual electrode layers 12
A thick layer 24 made of a conductive resin having a layer thickness of 5 μm is separately formed on the layers a to 12h to increase the layer thickness in advance, so that the nickel layers in the two common electrode layer terminal portions 13b and 13c are formed. A combined layer thickness of 22 and the solder layer 23;
Thick film layer 24 made of conductive resin, nickel layer 22 and solder layer 23 in a plurality of individual electrode layers 12a to 12h
And the thickness of the two common electrode layer terminals 13 on the substrate 11 after plating.
b, 13c and a plurality of individual electrode layers 12a to 12h
Are substantially the same. Therefore, even when this resistor is mounted on a printed circuit board on the back surface side, a soldering failure does not occur, and a resistor excellent in solderability can be obtained.

Further, since the thick film layer 24 made of a conductive resin system according to the embodiment of the present invention can be formed by firing at a relatively low temperature, the one using this method has higher durability. It is preferable. Further, as another material constituting the thick film layer 24 made of the conductive resin, a glaze thick film layer made of an alloy of silver and palladium may be used. It is sufficient that the thick film layers are formed in layers, and the thickness of the plurality of individual electrode layers 12a to 12h located on the back side of the substrate 11 from the beginning is larger than the thickness of the two common electrode layer terminal portions 13b and 13c. The same effect as in the embodiment of the present invention can be obtained even if the glaze-based thick film layer 21 made of an alloy of silver and palladium is formed so as to be thick.

In one embodiment of the present invention, the plurality of individual electrode layers 12a to 12h and the common electrode layer 13
And a plurality of resistance elements 14a to 14
4e, the DC resistance values are set to be equal to each other, but the DC resistance values are not necessarily equal to each other, and it is sufficient that the minimum DC resistance value is 10 KΩ or more. In this case, as the DC resistance increases, the difference in layer thickness between the plurality of individual electrode layers 12a to 12h and the common electrode layer 13 increases, so that it is not preferable to increase the DC resistance more than necessary.

In the above-described embodiment of the present invention, the plurality of individual electrode layers 12a to 12h and the common electrode layer 13
Since the resistance elements having a DC resistance value of 10 KΩ or more, which is smaller than the conventional resistance element of 47 KΩ or more, are used as the plurality of resistance elements 14 a to 14 e provided to electrically connect Current flows more easily to the layers 12a to 12h, and as a result, the outermost layer formed on the surface of the plurality of individual electrode layers 12a to 12h is a plating layer made of solder, that is, a nickel layer 22, a solder layer 23.
Therefore, the thickness of the common electrode layer including the plating layer whose outermost layer is made of solder does not become extremely thick as in the related art. Since the difference in thickness between the layers 12a to 12h is reduced, even when this resistor is mounted on a printed circuit board, soldering failure does not occur, and a resistor excellent in solderability can be obtained. It is.

Further, in one embodiment of the present invention,
As described with reference to FIG. 1, the description has been given of the resistor in which the two common electrode layer terminal portions 13b and 13c in the common electrode layer 13 are arranged diagonally, but as shown in FIG. Common electrode layer 32 and multiple individual electrode layers 33a
To 33h and a plurality of resistance elements 34a to 34d can also provide the same effect as that of the embodiment of the present invention. In FIG. 3, a plurality of resistance elements 3
4a to 34d are a common electrode layer 32 and a plurality of individual electrode layers 33.
a to 33h so as to partially overlap each other.

Further, a plurality of individual electrode layers 33a to 33
The same effect can be obtained even if the shape of h is a convex shape as shown in FIG. 1 or a concave shape as shown in FIG.

In the resistor according to the embodiment of the present invention configured as described above, a plurality of individual electrode layers 12a to 12h located on the back side of the substrate 11 separately contain silver having a thickness of 5 μm. Since the layer thickness is previously increased by forming the thick film layer 24 made of a conductive resin, there is no difference between the layer thicknesses of the two common electrode layer terminal portions 13b and 13c of 5 μm or more. In addition, the occurrence of connection failure during soldering can be almost eliminated, and the yield can be improved. Further, the two common electrode layer terminal portions 13
b, 13c nickel layer 22 or solder layer 23
Is the same as in the prior art, so that a plurality of individual electrode layers 1
About 3 times or less of each layer thickness in 2a to 12h,
Thereby, the common electrode layer terminal portions 13b after soldering,
Since large irregularities do not occur on the surface of the solder layer 23 in 13c, the conductive resin thick film layer 24 is hardly destroyed by the thermal deformation of the nickel layer 22.

[0026]

As described above, the resistor of the present invention comprises a substrate, a plurality of individual electrode layers provided so as to face side portions of the substrate, and an electrical connection between one of the individual electrode layers. Connected to the common electrode layer provided on the upper surface of the substrate and located between the plurality of opposed individual electrode layers,
A plurality of resistance elements provided so as to electrically connect the plurality of individual electrode layers and the common electrode layer; and a plating in which an outermost layer provided on the surfaces of the plurality of individual electrode layers and the common electrode layer is made of solder And a resistance element having a DC resistance value of 10 KΩ or more as the plurality of resistance elements. According to this configuration, the plurality of individual electrode layers and the common electrode layer are electrically connected. Is used, the DC resistance value is 10 KΩ or more, which is smaller than the conventional resistance element of 47 KΩ or more.
The current flows more easily to the plurality of individual electrode layers, and as a result, the outermost layer formed on the surface of the plurality of individual electrode layers becomes easier to form a plating layer made of solder. Only the layer thickness of the common electrode layer including the plating layer made of solder will not be extremely thick,
As a result, the difference in thickness between the common electrode layer and the plurality of individual electrode layers is reduced, so that even when this resistor is mounted on a printed circuit board, soldering failure does not occur, and the solderability is excellent. This has the effect that a resistor can be obtained.

[Brief description of the drawings]

FIG. 1 is a plan view of a chip-type network resistor according to an embodiment of the present invention.

FIG. 2 is an enlarged sectional view of a main part of the chip-type network resistor.

FIG. 3 is a plan view of a chip-type network resistor according to another embodiment of the present invention.

FIG. 4 is a plan view of a conventional chip-type network resistor.

FIG. 5 is a side view showing a soldering state of a conventional chip-type network resistor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Substrate 12a-12h Individual electrode layer 13 Common electrode layer 14a-14e Resistance element 22 Nickel layer 23 Solder layer 24 Thick film layer 31 Substrate 32 Common electrode layer 33a-33h Individual electrode layer 34a-34d Resistance element

Claims (2)

[Claims] 1. A substrate, a plurality of individual electrode layers provided to face side portions of the substrate, and a plurality of the individual electrode layers electrically connected to one of the individual electrode layers. A common electrode layer provided between the individual electrode layers and provided on the upper surface of the substrate; a plurality of resistance elements provided to electrically connect the plurality of individual electrode layers and the common electrode layer; And a plating layer provided on the surface of the individual electrode layer and the common electrode layer, the outermost layer being made of solder, and using a resistive element having a DC resistance value of 10 KΩ or more as the plurality of resistive elements. 2. A substrate, a plurality of individual electrode layers facing the side of the substrate, and extending from the upper surface of the substrate to the rear surface via the side surface, and electrically connecting one of the individual electrode layers to the substrate. And a common electrode layer provided on the upper surface of the substrate and positioned between the plurality of opposing individual electrode layers, and further having an end located from the upper surface of the substrate to the rear surface via the side surface. And a plurality of resistance elements provided so as to electrically connect the plurality of individual electrode layers and the common electrode layer, and an outermost layer provided on the surface of the plurality of individual electrode layers and the common electrode layer is formed of solder. And a plating layer
A resistor in which a thick film layer is separately formed on a plurality of individual electrode layers located on the back side of the substrate.