JPH04188658A - Surface mounting type semiconductor device - Google Patents

Abstract

PURPOSE:To enable an outer lead to be enhanced in strength and hardly deformed by a method wherein the outer leads protruding rectilinearly from the side of a package main body are formed V-shaped or U-shaped in cross-section. CONSTITUTION:If the outer leads 12 protruding rectilinearly in a lateral direction from the side of a package main body 11 are formed V-shaped in cross-section, they are hardly bent in a vertical direction and enhanced in mechanical strength, and as both the base side faces of the outer lead 12 can be soldered, the package main body 11 can be enhanced enough in soldering strength when it is mounted on a printed board. When an outer lead 22 is formed U-shaped in cross-section, a lead frame can be easily formed, and the package main body 11 can be enhanced more in soldering strength when it is mounted on a printed board. By this setup, an outer lead can be enhanced in mechanical strength and hardly deformed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a surface-mounted semiconductor device, and particularly to the shape of its external leads.

[Conventional technology]

The shape of the external lead of a conventional surface mount semiconductor device is s
OP (Small Outline Package), QF
P (quad flat package), etc., in which the external leads 32 protruding horizontally from the side of the package body 31 are bent downward and then made horizontal again (Fig. 3), SOJ (small outline package) J lead), PLCC (plastic leaded chip)
It was curved inward like a carrier (Figure 4).

[Problem to be solved by the invention]

Among the conventional surface mount semiconductor devices mentioned above, SOP,
Due to its lead shape, QFP has a disadvantage in that its strength is low and lead deformation is very likely to occur.

Also, SOJ and PLCC have the disadvantage that it is difficult to see the soldered parts on the board.

[Means to solve the problem]

In the surface mount semiconductor device of the present invention, the external leads linearly protruding from the side surface of the package body have a 7-shaped or U-shaped cross section.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIGS. 1(a), (b), and (C) are a perspective view, a plan view, and a side view of a first embodiment of the present invention.

In this embodiment, the package body 11 is made of plastic or the like.
It has an external lead 12 that projects linearly in the lateral direction from the side surface of the external lead 12, and the cross-sectional shape of the external lead 12 is V-shaped. Because it has a figure 7 shape, it is difficult to bend vertically, and not only does it have great mechanical strength, but it can also be soldered to both sides of the bottom, providing sufficient soldering strength when mounting it on a printed circuit board.

FIG. 2 is a side view of the second embodiment.

In this embodiment, since the cross-sectional shape of the external lead 22 is U-shaped, it is easy to form a lead frame, and there is an advantage that the soldering strength can be increased during mounting.

〔Effect of the invention〕

As explained above, the present invention has the effect of increasing the mechanical strength of the external lead and reducing lead deformation by making the cross-sectional shape of the external lead 7-shaped or U-shaped, without impairing solderability. This has the effect of realizing a surface-mount semiconductor device that can be mounted on a substrate.

[BRIEF DESCRIPTION OF THE DRAWINGS] Fig. 1 <a), (b) and (C) are perspective views, plan views and side views of the first embodiment of the present invention, and Fig. 2 is a diagram of the second embodiment. Partial side view, Figures 3 and 4 are SOP
FIG. 3 is a front view of a surface mounting semiconductor device which is a conventional example of SOJ structure. 11.21, 31.41...Package body, 12.
22, 32. 42...External lead.

Claims (1)

[Claims] A surface mounting semiconductor device characterized in that an external lead linearly protruding from a side surface of a package body has a V-shaped or U-shaped cross section.