JPS626698Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a semiconductor device in which a semiconductor integrated circuit (hereinafter referred to as IC) and a switch are integrated, and particularly to a lead frame thereof.

For example, a voltage generation IC such as an electronic volume
When a switch and a switch are used in pairs, the number of parts increases and the work required to attach them to the printed circuit board increases, which is not desirable when trying to assemble a large number of parts in a limited space. This was not necessarily the best method, as it resulted in lower product yields and an increased probability of wire breakage.

From this point of view, a semiconductor device has been proposed in which a switch and a semiconductor integrated circuit element are integrated into a lead frame. However, if a switch is formed by providing a recess in a package cage with limited dimensions,
It is easily affected by moisture, which causes deterioration of IC elements.
This has the disadvantage that it is difficult to maintain the reliability of the package.

The present invention was developed from the above-mentioned viewpoint, and provides a lead frame suitable for a semiconductor device that integrates an IC element and a switch, by increasing the creepage distance between the switch forming part and the IC element. It is an object of the present invention to provide a lead frame for a semiconductor device that is integrated with a switch in which an IC element incorporated in a package can withstand moisture.

The present invention will be explained below based on the drawings.
Note that the same parts in each figure are given the same reference numerals.

FIG. 1 shows an embodiment of a semiconductor device equipped with a switch according to the present invention. Terminal pins 2 are arranged in a package 1 in which an IC element is sealed with resin, and a switch is formed at the edge of the package 1. 3
is the movable axis of the switch. 4 is a spring, and 5 is a contact point. 6 is a locking part of the movable shaft 3, and is a concave part A of the package 1 in which the switch is installed.
protrudes inward. In the embodiment of the semiconductor device equipped with a switch shown in FIG. 2, the movable shaft 3 is housed in a frame 9, and the switch is formed integrally with the package.

FIG. 3 is a partially cutaway perspective view with the movable shaft 3 removed. Here, assuming that the terminal pins arranged in the package 1 are 2 ₁ , 2 ₂ , 2 ₃ , ..., the inner end of the outermost terminal pin 2 ₁ is exposed in the recess A of the package 1, and the switch A pair of contacts _2a are formed. The contact 2a exposed in the recess _A is formed wide to facilitate contact, and the tip of the contact _2a is formed narrow, and then buried in the package 1 again to form the curved part _2b. IC element 7
Terminal pin ₂₁ is connected to the IC by wiring 8.
It is connected to element 7. Further, referring to the lead frame in Fig. 4, reference numeral 1 is a package part that is molded with resin, and by forming the contact point _2a of the switch on the outermost terminal pin, the concave part A and the IC element are connected. 7, and forms a curved portion _2b to move them away from each other. That is, the package 1 is sealed with resin except for the recess A where the switch is formed.
Since it is a notch, the distance L between the IC element and the contact part is set so that it can withstand environmental conditions such as humidity, and the outermost terminal pin is used to form the contact 2 _a , and the curved part 2 _b is formed. This substantially increases the distance along the side surface of the terminal pin ₂₁ . By this,
It is possible to maintain reliability against moisture in a package containing an IC element, and a switch can be easily formed within the package.

As for the movable shaft of the switch, the one shown in FIGS. 5 and 6 is used. FIG. 5 is a side view of the movable shaft 3 of the switch, and a leaf spring-like contact 5 is provided at the bottom of the movable shaft 3, and 4 is a spring. The IC is sealed by inserting the movable shaft 3 into the recess A formed at the edge of the package 1 shown in FIG. The switch is integrally formed in the package cage. FIG. 6 shows a configuration in which the movable shaft 3 is housed in a frame 9. As shown in FIG. Although the contact 5 is made of conductive rubber, it is not limited to this, and various materials and shapes are possible. In this way, by using part of the lead frame as the contact point of the switch, the switch and IC can be integrated by simply attaching the movable shaft to the recess of the package.

As described above, the lead frame for a semiconductor device equipped with a switch according to the present invention has a structure in which terminal pins are exposed in the recessed portion of the package, and the exposed terminal pins are used as contacts of the switch. Further, the outermost terminal pin is used as a contact point of the switch, and by extending to the vicinity of the IC element and forming a curved portion _2b , it is possible to maintain a creepage distance between the contact point and the IC element. As a result, the reliability of the package can be improved and the IC element can be protected from moisture, making it possible to easily form a switch by providing a notch in the IC package.

[Brief explanation of the drawing]

1 and 2 are semiconductor devices equipped with a switch according to the present invention, FIG. 3 is a partially cutaway exploded perspective view of the semiconductor device shown in FIG. 1, and FIG. 4 is an illustration of a lead frame according to the present invention. FIG. 5 is a plan view showing the embodiment, FIG. 5 is a side view of the movable shaft, and FIG. 6 is a cross-sectional perspective view of the movable shaft housed in the frame. 1: Package cage, 2: Terminal pin, 2 _a : Contact,
2 _b : curved portion, A: recessed portion.

Claims (1)

[Scope of utility model registration request] At least one pair of terminal pins of a lead frame connected to a semiconductor integrated circuit element and integrally resin-molded form a contact point of a switch, and an inner end of the terminal pin is connected to the contact point and the semiconductor integrated circuit element. 1. A lead frame for a semiconductor device equipped with a switch, characterized in that a curved portion is formed between the switch and the lead frame to substantially lengthen the creepage distance of the lead frame from the switch to a semiconductor integrated circuit element.