JPH10290058A - Printed-circuit board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To mount a package on an identical printed-circuit board even when its shape is changed by a method wherein a land at a ball grid array(BGA) or the like whose package size is small is arranged at the inside of a land at a quad flat package(QFP) or the like whose package size is large so as to make centers of the respective lands agree. SOLUTION: Lands 2 at a BGA whose package size is smaller than that of a QFP or at a chip size package(CSP) are arranged at the inside of lands 1 at the QFP whose package size is large, and they are arranged in such a way that centers of the respective lands 1, 2 agree. Then, the lands 1, 2 to which terminals having the same function at the QFP package and the BGA package are connected by using patterns 3 or via holes 4, and the QFP and the BGA have a structure in which they can be mounted on an identical printed- circuit board even when either the GFP or the BG is selected.

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, and more particularly to a land arrangement and a wiring method thereof.

[0002]

2. Description of the Related Art Conventionally, in a printed circuit board on which a semiconductor package such as a QFP is mounted, for example, in a printed circuit board on which a QFP is mounted, a BGA having the same function as the QFP and having a different package form is used. In the case of replacing with a BGA, another printed circuit board is manufactured by changing the land of the QFP of the printed board having the land on which the QFP can be mounted to the land on which the BGA can be mounted.
To be installed.

[0003]

As is apparent from the above, according to the conventional method, in a printed circuit board on which a certain type of package is mounted, only the shape of the package having exactly the same function is obtained. When replacing with a different package, there is a problem that the printed circuit board must be changed to another printed circuit board having a land according to the shape of the package.

[0004] It is an object of the present invention to enable mounting on the same printed circuit board without manufacturing a new printed circuit board even if the shape of a package mounted on the printed circuit board is changed.

[0005]

In order to achieve the above object, in a printed circuit board of the present invention, a land such as a BGA or CSP having a small package size is provided inside a land such as a QFP having a large package size. Lands are arranged so that the centers of the lands coincide, or lands such as QFP and lands such as BGA and CSP are arranged in two rows, and lands to which terminals having the same function are to be connected in each package are connected. Since they are connected by pattern wiring, they can be mounted on the same printed circuit board even if the shape of the package mounted on the printed circuit board changes.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows an example in which a BGA land 2 having a smaller package size than a QFP is arranged inside a land 1 of a QFP having a larger package size so that the centers of the lands coincide with each other. FIG. 4 shows an example in which lands of QFP and lands of BGA are arranged in two rows. In both FIGS. 1 and 4, the lands to which the terminals having the same function of both packages are connected are connected by the wiring pattern 3 and the via hole 4, and the same print is made regardless of whether QFP or BGA is selected. It has a structure that can be mounted on a substrate.

FIGS. 2 and 5 show Q in FIGS. 1 and 4, respectively.
In this example, the FP land 1 is selected, and the QFP 5 is connected to the QFP land 1 by the lead terminal 6 of the QFP.

Next, FIGS. 3 and 6 show examples in which the BGA lands 2 of FIGS. 1 and 4 are selected and the BGA 7 is connected to the BGA lands 2 by the BGA ball terminals 8.

[0009]

Since the present invention is configured as described above, it has the following effects.

First, lands having different package shapes are arranged on the same printed circuit board, and lands to be connected to terminals having the same function in each package are connected by pattern wiring. Therefore, even if the shape of the package mounted on the printed circuit board changes, it is not necessary to manufacture a new printed circuit board, and the same substrate can be shared.

Therefore, second, in a mounting factory for mounting a semiconductor package on a printed circuit board, the package to be mounted can be selectively used according to the technical level of mounting the semiconductor package. Alternatively, the semiconductor package can be selectively used in accordance with the supply level of the supply side.

Third, as shown in FIG. 1, when the BGA lands are arranged inside the QFP lands, the mounting density of the printed circuit board is not impaired, and when the centers of the lands are matched, In the mounting program of the mounting machine, the coordinate values can be shared without changing.

[Brief description of the drawings]

FIG. 1 shows a BGA land inside a QFP land.
It is a figure which shows the case where it arrange | positions so that the center of each land may correspond.

FIG. 2 is a diagram showing a case where a QFP is mounted on FIG. 1;

FIG. 3 is a diagram showing a case where a BGA is mounted in FIG. 1;

FIG. 4 is a diagram showing a case where lands of QFP and lands of BGA are arranged in two rows.

FIG. 5 is a diagram showing a case where a QFP is mounted in FIG. 4;

FIG. 6 is a diagram showing a case where a BGA is mounted in FIG. 4;

[Explanation of symbols]

 1 land of QFP 2 land of BGA 3 wiring pattern 4 via hole 5 QFP

Claims (3)

[Claims] 1. Quad Flat Package
(Hereinafter abbreviated as QFP), Ball Grid Arr
ay (hereinafter abbreviated as BGA), Chip Size P
In a printed circuit board on which a semiconductor package such as a package (hereinafter abbreviated as CSP) is mounted, a land such as a BGA or CSP having a small package size is arranged inside a land such as a QFP having a large package size, and a QFP etc. arranged outside the land. Land and BGA and C arranged inside
A printed circuit board wherein lands to be connected to terminals having the same function in respective packages of lands such as SP are connected by pattern wiring. 2. The printed circuit board according to claim 1, wherein a land such as a QFP disposed outside and a center of a land such as a BGA or CSP disposed inside coincide with each other. 3. Lands such as QFP and lands such as BGA and CSP are arranged in two rows, and lands to be connected to terminals having the same function in each package are connected by pattern wiring. Printed circuit board.