JPH025543Y2 - - Google Patents

Description

[Detailed explanation of the idea] (Industrial application field) This invention relates to a semiconductor device.

(Prior art) Resin packages are used in semiconductor devices such as transistors, diodes, and IC circuits, and in this case, the terminals that are drawn out are formed across the side and back surfaces of the package. There is also a leadless type.

When loading this semiconductor device onto a printed circuit board, the terminal section formed on the back side of the package is brought into direct contact with the conductive foil on the printed circuit board, and the terminal section formed on the side surface of the package and the conductive foil are soldered. I try to do that.

Figure 4 shows the soldering state described above, where 1 is the printed circuit board, 2 is the conductor foil, 3 is the package, and 4 is the soldering state.
is a terminal. The terminal 4 is connected to the side surface 3a of the package cage 3.
It is composed of a terminal portion 4a along the back surface 3b, and a terminal portion 4b along the back surface 3b.

When soldering, temporarily attach the package 3 to the surface of the printed circuit board 1 with adhesive so that the terminal portion 4b is in contact with the conductor foil 2, turn the printed circuit board 1 over as shown in the figure, and solder the surface 3c of the package 3. It is immersed in the solder 5 as it is, with the tip facing downward.

However, when dipping into the solder 5 as described above, the resin constituting the package 3 is difficult to wet with the solder regardless of its type.
Although the surface 3c of the package 3 is pressed against and comes into contact with the solder 5, the solder 5 is attached to the terminal portion 4a of the terminal 4.
Therefore, there is a space 6 along the side surface of the package 3 where no solder adheres.

Therefore, it is inevitable that soldering between the terminal portion 4a and the conductive foil 2 becomes difficult. Such a phenomenon appears conspicuously when the package 3 is extremely small (for example, about 2 to 3 mm in width and 1 to 2 mm in height).

(Problems to be Solved by the Invention) The purpose of this invention is to ensure that the terminals provided on the package and the conductive foil on the printed circuit board are soldered securely.

(Means for solving the problem) This invention has a first terminal part on the back side of the package that is flush with the back side and contacts the conductor foil on the printed circuit board, and a first terminal part that is in contact with the conductor foil on the printed circuit board. , forming a second terminal part continuous to the first terminal part and soldered to the conductor foil;
A third terminal part is provided on the surface of the package, which is connected to the second terminal part, and allows the solder that comes into contact with the surface to flow into the second terminal part during soldering. Each of the second terminal portions formed to mate with each other has a first extended terminal portion on opposite side edges thereof extending in the width direction of the second terminal portion, and a first expanded terminal portion extending toward the width of the second terminal portion. A second expansion terminal portion is formed on each side edge where the expansion terminal portion is not expanded in a direction opposite to that of the first expansion terminal portion, and the expansion area of the second expansion terminal portion is larger than that of the first expansion terminal portion. It is characterized by a longer .

(Example) An example of this invention will be described with reference to FIGS. 1 to 3. 11 is a resin package of the semiconductor device, 12 is a terminal, and the side surface 11a of the package 11 is
Terminal part 12a (second terminal part) along the back surface 11b of package 11, terminal part 12b (first terminal part) along
In addition to the terminal section of the package 11,
It is formed by a terminal portion 12c (third terminal portion) along 1c.

When soldering, temporarily fix the back surface 11b of the package 11 to the printed circuit board 1 with adhesive,
At this time, the terminal portion 12b is brought into direct contact with the conductor foil 2.

In this case, when temporarily fixing the package 11,
If the back surface 11b is not in contact with the printed circuit board 1, temporary fixing with adhesive cannot be performed. Moreover, at this time, it is necessary that the terminal portion 12b be in contact with the conductive foil 2. In order to satisfy this requirement, the front surface of the terminal portion 12b and the back surface 11b of the package 11 are made to be on the same plane as shown in the figure.

After temporarily fixing the package 11 to the printed circuit board 1 as described above, the printed circuit board 1 is turned over so that the front surface 11c faces downward, and then immersed in the solder 5. This is no different from the conventional case.

However, since the surface 11c is pressed against the solder 5 at this time, the terminal portion 12c is also pressed against the solder 5 and comes into forcible contact.
Since the terminal 12 is made of metal, it is much more easily wetted by solder than the resin that constitutes the package 11, so that the solder 5 can easily flow from the terminal portion 12c to the terminal portion 12a. Become.

FIG. 2 shows the state at this time, and no space portion 6 as shown in FIG. 4 is formed here. By contacting the terminal portion 12a with the solder in this way, the terminal portion 12a and the conductor foil 2
This means that it will definitely be soldered.
FIG. 3 shows the state after soldering.

Furthermore, in this invention, as shown in FIG.
It is suitable for use in a configuration in which they are formed in pairs so as to be adjacent to each other.

In this case, each pair of terminal portions 12a is provided with a terminal portion 12a on each opposite side edge thereof.
An extension terminal part 12e (first extension terminal part) is formed which extends in the width direction of the extension terminal part 12e, and an extension terminal which extends in the direction opposite to the extension terminal part 12e is formed on the other non-opposed side edge. A portion 12f (second extended terminal portion) is formed.

With this configuration, when the immersed printed circuit board is pulled up from the solder bath for soldering, the expansion terminal portion 12 is placed higher than the expansion terminal portion 12e.
Since f is formed by lengthening its extended region,
The solder is strongly attracted to the extended terminal portion 12f side.

Therefore, even if the terminals 12 are arranged side by side on the side surface of the package 11, it is possible to prevent the terminals 12 from being bridged by solder.

Since the soldering area is expanded by the amount of each expansion terminal section 12e and 12f,
Solder flow and adhesion can be improved.

(Effects of the invention) As detailed above, according to this invention, soldering to the printed circuit board can be ensured by a simple configuration in which terminals are formed extending from the back side of the package to the front side. As well as being able to
This has the effect of preventing bridges between adjacent terminals due to solder.

[Brief explanation of drawings]

Figure 1 is a perspective view showing an embodiment of this invention;
3 is a sectional view showing the soldered state, FIG. 3 is a sectional view showing the state after soldering, and FIG. 4 is a sectional view showing the conventional soldering state. 11...Package, 11a...Side, 11b
... Back side, 11c... Front side, 12... Terminal, 12
a...second terminal part, 12b...first terminal part,
12c...Third terminal section, 12e...First extension terminal section, 12f...Second extension terminal section.

Claims (1)

[Scope of utility model registration request] When soldering, the back side of the resin package is temporarily fixed with adhesive in contact with the printed circuit board, and the conductive foil on the printed circuit board is flush with the back surface of the resin package. first contact
In the semiconductor device, a terminal portion of the package is formed, and a second terminal portion is formed on a side surface of the package, the second terminal portion being connected to the first terminal portion and soldered to the conductive foil. A third terminal part is provided on the surface, which is connected to the second terminal part, and allows the solder that comes into contact with the surface to flow into the second terminal part during soldering. Each of the second terminal parts formed adjacent to each other has a first extended terminal part on the opposite side edge so as to expand in the width direction of the second terminal part. Second expansion terminal portions are formed on side edges of the second terminal portions that do not face each other so as to expand in a direction opposite to the first expansion terminal portion, and the first expansion terminal portion A semiconductor device in which the extended region of the second extended terminal portion is longer than the extended region of the second extended terminal portion.