JPH067248U - SMD flat package - Google Patents

Abstract

(57) [Abstract] [Purpose] SMD (Su-rface Mount Devise) flat package with lead terminals protruding from the side of the package body, flat package structure that does not deform the lead terminals during handling. The purpose is to provide. [Structure] The guard member 3 having a tip protruding from the lead terminal 2 is configured to project from the side surfaces of the four corners of the package body 1.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an SMD flat-type package in which lead terminals are arranged so as to protrude from the side surface of the package body.

Recently, electronic devices have been miniaturized and multi-functionalized so that high density mounting of printed wiring boards has progressed, and the mainstream of integrated circuit packages has changed from the lead terminal insertion type to the surface mounting type. ing.

The SOP type and the QFP type in which the lead terminals are arranged on the side surface of the surface mount type package are extensions of the conventional DIP type and are often used because they are easy to handle and do not increase the cost. Since it is only placed on the footprint and not inserted into the printed wiring board, the terminals can be made smaller and the number of terminals can be increased, but the strength is weakened, so handling is required. .

[0004]

[Prior art]

 FIG. 4 shows a conventional SOP type SMD. In the flat type SMD, as shown in FIG. 4, an example is shown in FIG. 4, in which Z-shaped bent lead terminals 2 are provided in a row from both longitudinal sides of a rectangular parallelepiped package body 19.

The flat tip portion 21 of the lead terminal 2 is placed on the footprint of the printed wiring board and is connected by soldering. Therefore, the lower surface of the tip portion 21 is formed to have a size that allows a slight business trip from the bottom surface of the package body 19.

Such an SMD is also taped to an adhesive paper tape, loaded into an automatic mounting machine, and automatically mounted in a predetermined position on a printed wiring board.

[0007]

[Problems to be solved by the device]

 However, due to the demand for higher productivity, as the mounting speed increases, the moving speed of the cartridge that stores the parts in the automatic mounting machine becomes faster, and in many cases the inertial force impacts the adjacent cartridge. I came. In this case, the SOP type SMD is peeled off from the adhesive tape and dropped, deforming the lead terminal 2, and especially the lead terminal 2 at the end portion is deformed and bent. As described above, the SOP type SMD having the deformed bend causes the reliability to be deteriorated if the lead terminal 2 is manually modified, and therefore is generally scrapped, which is against productivity. In the case of the QFP type SMD, the circuit scale of the LSI is large and expensive, the number of spares is small, and such disposal may hinder the production. Since both ends of each row of lead terminals 2 often cause deformation and bending, if this is made into a dummy terminal that is not connected in a circuit, most of the relief can be performed, but an extra lead terminal is used as a dummy terminal. It becomes necessary, and the size of the package body 19 becomes large. There were problems such as.

In view of the above problems, it is an object of the present invention to provide a flat type package structure in which the lead terminals are not deformed in handling.

[0009]

[Means for Solving the Problems]

 As shown in FIG. 1, in the flat type SMDs 5 and 55 in which the lead terminals 2 are arranged so as to project from the side surfaces of the package bodies 1 and 11, the guard members 3 and 33 whose front portions project from the lead terminals 2 are provided. This is achieved by the flat type package of SMD5,55 of the present invention, which is provided on the side surfaces of the four corners of the package bodies 1,11 so as to project.

[0010]

[Action]

 That is, the four corners of the package bodies 1 and 11 are located at both ends of the row of the lead terminals 2, and the guard members 3 and 33 protruding from the lead terminals 2 are provided there, so that the adhesive tape can be removed during handling. Even if it peels off, the guard members 3, 33 protruding at the outermost end collide with a flat surface such as a floor surface, and the lead terminal 2 is intact unless it is damaged.

[0011] Thus, according to the present invention, it is possible to provide a flat type package structure in which the lead terminals are not deformed from the viewpoint of handling.

[0012]

【Example】

 Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings. Throughout the drawings, the same reference numerals indicate the same objects. FIG. 2 shows an SOP type package according to an embodiment of the present invention, and FIG. 3 is an enlarged view of various guard members according to another embodiment of the present invention.

In the SOP type package of one embodiment shown in FIG. 2, the guard members 3 protruding from the four corners of the package body 1 are integrally molded from the prismatic shape shown in the principle diagram of FIG. 1 to the triangular prism shape. The dimension up to the tip is equal to or more than the shape of the lead terminal 2 bent in a Z shape in any direction.

Therefore, in case of dropping and colliding with a flat surface, the guard member 3 is always contacted, and the lead terminal 2 is prevented from being directly contacted and deformed. Further, the SOP type SMD5 is usually reflow-soldered to a printed wiring board, but sometimes it is flow-soldered by applying a solder jet. At this time, the guard member 3 becomes a wall, It is difficult for the flow solder to flow around to the lead terminal 2 and the soldering failure may occur, but this action is made into a triangular wall to eliminate the soldering failure.

Further, FIG. 3 shows various guard members according to another embodiment, and FIG. 3 (a) shows a triangular pillar-shaped guard member 3, but the direction of the slope is different from that of FIG. Inclining them away from each other in the direction of 2 to eliminate defects in flow soldering, and since the guard member 3 can be arranged closer to the lead terminals 2, it is possible to suppress an increase in the length dimension of the package body 1. You can

Further, FIG. 3 (b) shows the guard member 3 of FIG. 3 (a) in which a groove-shaped concave portion 31 is provided on the surface in contact with the printed wiring board to improve the flow of the flow solder. Even in the case of reflow soldering, the distance between the lead terminal 2 can be narrowed.

[0017]

[Effect of device]

 As described above, the flat type package structure of the present invention prevents the lead terminals from being deformed from the viewpoint of handling, and the SOP type SMD can also be subjected to flow soldering. There is no need to change the mold type, and there is no cost increase.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of the principle of the present invention.

FIG. 2 is a SOP type package according to an embodiment of the present invention.

FIG. 3 is an enlarged view of various guard members according to another embodiment of the present invention.

FIG. 4 is an example of a conventional SOP type SMD.

[Explanation of symbols]

1,11,19 Package body 2 Lead terminal 3,
33 Guard member 5,55 SMD 21 Tip 31
Groove recess

Claims (1)

[Scope of utility model registration request] 1. A SM of a flat type package in which lead terminals (2) are arranged so as to project from the side surface of the package body (1).
In D, the guard member (3) whose tip protrudes from the lead terminal (2)
A flat type SMD package characterized by being provided on the four corners of the package body (1).