JPS6127183Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to the shape of an IC package.

Recently, there has been a demand for smaller and thinner electronic devices with built-in so-called microcomputer configurations consisting of ROM, RAM, CPU, etc.
Along with this, efforts are being made to make effective use of the mounting area by evaluating the miniaturization of each component used and the optimal placement of components. Among these, IC packages such as ROM and RAM, which occupy a relatively large area, are being replaced from the so-called dual in-line type with pin placement on both sides to the so-called quad type with pin placement in four directions. Today, quad IC packages are used exclusively for small electronic devices.

However, even if such a quad-type IC package is used, there is a limit to how effectively a certain area can be used, and therefore, for example, when using a large number of ROMs, a multilayer printed wiring board must be used. There were other inconveniences.

The present invention eliminates the above-mentioned disadvantages and improves the shape of the IC package, thereby making it possible to substantially reduce the mounting area.

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

Figure 1 is a diagram explaining the procedure for mounting an IC package, which is an embodiment of the present invention, on a printed circuit board, Figure 2 is a perspective view of the external appearance after six IC packages are mounted, and Figure 3 is an example of usage. It is a diagram.

In the figure, P is the IC package main body, and it is a so-called quad-type package in which leads L are provided on the sides in four directions.

A convex portion T is provided at the center of the top surface of each IC package cage, and a concave portion O is provided at a position corresponding to the convex portion T on the bottom surface, respectively.
The convex portion T is formed so as to fit into the concave portion O.

X is a silicon chip sealed in package P, and this chip is connected to lead L by wire B.
It is bonded with. On the other hand, the leads L are attached along the wall surface of the package as shown in the figure, one of which is bonded to the silicon chip has been done. This is so that when the convex part T of another package P is fitted into the concave part O of the package P, it is held elastically. Therefore, in this case, it is desirable that the leads L be made of an elastic material.

The IC package P configured as described above is fixed to the pattern C on the printed circuit board PWB with solder S, and when five IC package P are stacked on top of it with their convex and concave parts aligned, the result is shown in Figure 2. As shown in the figure, a total of six IC packages _P1 to _P6 are mounted on the printed circuit board PWB. In this case, the common leads L of each IC package P are in contact with each other at the same time as they are stacked, and are in electrical contact with each other. Therefore, it is not necessary to fix the common leads L of each package with a bander or the like after stacking the IC packages P. do not have.

The stacked IC packages P, for example ROM packages ROM ₀ to ROMn, are generally connected to a central processing unit CPU equipped with an input/output controller I/O, RAM for temporary storage of data, etc., as shown in FIG. It can be accessed arbitrarily using the selector.

As described above, according to the present invention, an arbitrary number of IC packages can be placed at the same location by improving the shape of the IC package.
IC packages can be stacked and mounted, greatly reducing the mounting area.
Furthermore, electrical and mechanical connections can be made simply by stacking the IC packages, so the number of layers in the IC package can be easily changed. Furthermore, since the structure is very simple and the lead L is used as an elastic piece for fixing and holding the package, it can be manufactured at low cost.

[Brief explanation of the drawing]

Figure 1 is a diagram explaining the procedure for mounting an IC package, which is an embodiment of the present invention, on a printed circuit board, Figure 2 is a perspective view of the external appearance after six IC packages are mounted, and Figure 3 is an example of usage. It is a diagram. P is the IC package, L is the lead, PWB is the printed circuit board, S is the solder, B is the wire, and C is the wiring pattern.

Claims (1)

[Scope of utility model registration request] A convex connector part with leads arranged on the outer peripheral wall is provided approximately in the center of the top surface of the package body,
Further, a concave connector part is provided on the bottom surface at a position corresponding to the convex connector part, and the concave connector part is formed by guiding one of the leads to the inner circumferential wall, and both the connector parts can be electrically and mechanically attached to each other. An IC package characterized by being formed so as to have the following relationship.