JPH0766543A - Printed board - Google Patents

Abstract

PURPOSE:To reduce the gap between chip components in a state that the chip components are arranged in series in the longitudinal direction and to make possible the improvement of the mounting density of the chip components by a method wherein a common land, to where at least two pieces of chip-shaped circuit components can be made an electrical connection in common, is provided. CONSTITUTION:Chip components 11a and 11b, which are a 2125 type square- shaped chip capacitor, for example, are made to arrange in series in such a way that the respective one end of the components 11a and 11b is made a Shared connection to a common land 20a. Moreover, the respective other one end of the components 11a and 11b is made to connect to lands 13a and 13b. The interval between the components 11a and 11b in such a state can be reduced to a dimension (a), which is limited due to the mounting accuracy of a chip component mounter. The dimension (a) is the smallest length between chips in the mounting accuracy of the chip component mounter, is decided in every mounter and the mounting density of the chip components can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printed circuit board applied to various electronic devices, and more particularly to a printed circuit board in which chip-shaped circuit components are arranged in series.

[0002]

2. Description of the Related Art When a wiring pattern is formed on a substrate by using chip-shaped circuit components such as resistors and capacitors (hereinafter referred to as chip components), the higher the chip component mounting density, that is, the narrower the chip component spacing, Many chip components can be mounted on one board, and the board can be miniaturized. Figure 5 shows a small rectangular chip capacitor (chip component).
FIG. One of such rectangular chip capacitors
Two types of 2125 type chip capacitors 1
Is formed according to the standard shown in FIG. 5 having a length (L) of about 2 mm, a width (W) of about 1.25 mm and a thickness (t) of about 0.6 mm.

FIG. 6 shows a configuration in which chip components such as the capacitor 1 are arranged in series in the longitudinal direction. In particular, FIG. 6 (a)
Shows a plan view, and FIG. 6 (b) is a sectional view taken along line XX 'in FIG. 6 (a). In FIG. 6A, the solder (4 in FIG. 6B) is omitted in order to make the land arrangement particularly easy to understand. As shown in FIGS. 6A and 6B, two chip parts 1a and 1b are provided on the lands 3a and 3b and the lands 3c and 3d, respectively, which are arranged on the printed circuit board 2. Are connected in series by soldering (solder: 4). In such a serial arrangement of the chip components 1a and 1b, when the above-mentioned 2125 type chip components are used, the distance between the center lines of the lands associated with the respective chip components (and thus the center lines between the respective chip components) is 3. For a chip component having a length of 5 mm and a length of 2 mm, the distance between the components is 1.5 mm.

[0004]

Each of the above chip parts 1
The spacing between a and 1b has conventionally been limited due to various restrictions due to board design accuracy including land pattern design component placement for optimizing the amount of solder, mounting accuracy of a mounting machine for mounting chip components on a substrate, and the like. It could not be made shorter than about 1.5 mm described above. Therefore, it is difficult to improve the mounting density in the conventional serial arrangement configuration of the chip components 1a and 1b as shown in FIG.

It is an object of the present invention to provide a printed circuit board which can reduce the chip component interval and improve the mounting density when the chip components are arranged in series in the longitudinal direction.

[0006]

A printed circuit board according to the present invention as defined in claim 1 is a printed circuit board in which at least two chip-shaped circuit components are arranged in series,
It is characterized in that a common land capable of sharing electrical connection is provided for the at least two chip-shaped circuit components.

According to a second aspect of the present invention, in the printed circuit board according to the first aspect, the chip-shaped circuit components of the printed circuit board according to the first aspect are arranged at a minimum interval of mounting accuracy of the chip-shaped circuit component mounting machine. It is characterized in that lands corresponding to the parts are provided.

According to a third aspect of the present invention, there is provided a printed circuit board according to the first aspect, wherein a concave portion is provided at a central portion of a side surface of the common land of the printed circuit board according to the first aspect.

According to a fourth aspect of the printed circuit board of the present invention, the width of the common land in the longitudinal direction of series arrangement of the chip-shaped circuit components of the printed circuit board of the first aspect is smaller than that of the land other than the common land. It is also characterized in that

[0010]

According to the printed circuit board of the present invention, since at least two chip-shaped circuit components are provided with a common land capable of sharing electrical connection, the chip-shaped circuit components can be separated from each other by a chip interval. It becomes possible to suppress the mounting accuracy of the mounting machine to a lower limit value, for example, to about 0.5 mm, and it is possible to improve the mounting density.

According to the printed circuit board of the second aspect, the chip-shaped circuit components are arranged at the minimum interval of the mounting accuracy of the chip-shaped circuit component mounting machine, and the lands corresponding to the chip-shaped circuit components are provided. The chip-shaped circuit components are mounted on the predetermined land at the minimum interval, and the mounting density can be improved.

According to the third aspect of the present invention, since at least two chip-shaped circuit components are provided with common lands capable of sharing electric connection, the chip-shaped circuit components can be separated from each other by a chip interval. Only the accuracy of the mounting machine can be limited, for example, it can be reduced to about 0.5 mm,
The mounting density can be improved, and since the recess is provided in the central portion of the side surface of the common land, it is possible to prevent the chip components from being disadvantageously attracted to each other by the solder.

Further, according to the printed circuit board of the fourth aspect, since the common land capable of sharing the electrical connection is provided for at least two chip-shaped circuit components, the component intervals of the chip-shaped circuit components can be reduced. Only the accuracy of the chip mounting machine can be limited to, for example, about 0.5 mm, and mounting can be improved, and at the same time, the width of the common land in the longitudinal direction of the serial arrangement of the chip-shaped circuit components is set to the common width. Since the width of the lands other than the lands is larger than that of the lands, there is a margin against a deviation when soldering the chip component to the common land, and stable mounting is possible.

[0014]

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

1A and 1B are views showing an embodiment of a serial arrangement of chip parts according to the present invention. In particular, FIG. 1A is a plan view, and FIG. 1B is a view of Y- of FIG. 1A. It is a Y'sectional view.
Similar to FIG. 6A, FIG. 1A does not show the solder 14 for facilitating understanding of the land arrangement.

As shown in FIG. 1, in this embodiment, the chip components 11a and 11b, which are the above-mentioned 2125 type rectangular chip capacitors, are arranged in series so that one ends thereof are commonly connected to the common land 20a. The other ends of the chip component 11a and the chip component 11b are connected to the lands 13a and 13b, respectively. The chip component interval in such a state can be reduced to the dimension a limited by the mounting accuracy of the chip component mounter.

In FIG. 1, b1 and b2 are effective solder lengths (land lengths) in the longitudinal direction with respect to each electrode of each chip part.
And is determined by the electrode shape of each chip component. a
Is the minimum inter-chip component distance of the mounting accuracy of the chip component mounter and is determined for each mounter. Therefore, common land 20
By setting the length of a to a + 1/2 × b1 + 1/2 × b2, for example, the minimum length c for mounting the two chip components 11a and 11b can be obtained, which can increase the mounting density.

FIGS. 2 and 3 are plan views showing various shapes formed by using the serial arrangement of the chip parts shown in FIG.
2 shows a case where a large number of chip components are arranged in series, while FIG. 3 shows a case where the chip component series arrangements shown in FIGS. 1 and 2 are simultaneously performed on a substrate. 2 and 3 are both shown in FIG.
As in (a), the illustration of the solder 14 is omitted in order to clearly show the land arrangement.

First, in FIG. 2, four chip parts 11c,
11d, 11e, 11f are common lands 20b, 20c,
It is arranged in series between the land 13c and the land 13d via the 20d. By interposing a large number of common lands in this way, a large number of chip components can be mounted at high density.

Next, in FIG. 3, the chip components 11a and 11b arranged in series as shown in FIG. 1 are provided with a narrow component interval through the common land 20a, and the chip components 11c arranged in series as shown in FIG. , 11d, 11e, 11f are provided via common lands 20b, 20c, 20d.
In this way, the chip components arranged in series can be arranged in a reduced size by various combinations or arrangement patterns by interposing a large number of common lands, and as a result, the mounting density can be improved.

Various shapes can be considered for the common land shown in the above embodiment in order to prevent the reliability of soldering of chip parts and the deviation of parts due to the surface tension of solder. FIG. 4 is a plan view showing a state in which chip parts are arranged in series by using various common land shapes in which a concave portion is formed in the central portion. Particularly, in FIG. 4A, the concave portion of the common land is provided in a tapered shape. In FIG. 4 (b), the recess of the common land is provided in a curved shape. In FIG. 4, the distance between the chip component 11g and the chip component 11h is set to 0.5 mm, which is a value limited by the mounting accuracy of the chip component mounter, and the recess is formed at the center of the common land. The solder prevents the chip components from being pulled together.
Further, by forming the concave portion in the central portion of the common land, it is possible to inevitably have a spread on both sides of the common land, and it is possible to improve the solderability on the side surface of the chip component.

[0022]

As described above, according to the present invention, when the chip-shaped circuit parts are arranged in series, the land pattern of the common part (common land) is made to be one to reduce the chip part interval. This makes it possible to improve the packaging density.

Further, by forming the common land according to the present invention into a predetermined shape, it becomes possible to improve the solderability of the chip component.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of a printed circuit board in which chip components are arranged in series according to the present invention.

FIG. 2 is a plan view of a printed circuit board having a serial arrangement configuration of a large number of chip components according to the present invention.

FIG. 3 is a plan view of a printed circuit board having a serial arrangement configuration of the chip components of FIGS. 1 and 2.

FIG. 4 is a plan view showing an example of a common land shape (a recess is formed in the central portion) according to the present invention.

FIG. 5 is a perspective view for explaining the shape of a chip capacitor.

FIG. 6 is a diagram showing a printed circuit board in which chip components are arranged in series by a conventional mounting method.

[Explanation of symbols]

1a, 1b, 11a, 11b ... 11h Chip parts 2, 12 Printed circuit boards 3a, 3b, 3c, 3d, 13a, 13b ... 13f
Land 4,14 Solder 20a, 20b, 20c, 20d, 21a, 21b, 2
2 common land

Claims (4)

[Claims] 1. A printed circuit board in which at least two chip-shaped circuit components are arranged in series, and a common land which can share electrical connection with the at least two chip-shaped circuit components is provided. Printed circuit board characterized by. 2. The chip-shaped circuit component is arranged at a minimum interval of mounting accuracy of a chip-shaped circuit component mounter, and lands corresponding to the chip-shaped circuit component are provided. Printed board. 3. The printed circuit board according to claim 1, wherein a concave portion is provided in a central portion of a side surface of the common land. 4. The printed circuit board according to claim 1, wherein the width of the common land in the longitudinal direction of the serial arrangement of the chip-shaped circuit components is larger than the width of the land other than the common land.