JPH1146052A - Package structure and method of integrated circuit device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an IC which is quick disconnectable with respect to a PWB(printed wiring board), eliminating the soldering for packaging on the PWB. SOLUTION: A lock pin 2 is inserted into a fitting hole 3, made in a PWB 5 to plunge a substrate 21 onto the PWB 5, for making a terminal 1 abut against a pad 4 on the PWB 5 to bring about a compressed state. In such a constitution, the diameter of the fitting hole 3 is nearly equivalent to that of the lock pin 2 but smaller than that of an expanding part 22, which is once made smaller due to the elastic deformation, when the lock pin 2 is inserted into the fitting hole 3 but returns to a larger state, when thrusting through the backside of the PWB 5, so that the lock pin 2 does not come out of the fitting hole 3, thereby enabling the terminal 1 to fix an IC 20 to the PWB 5 in the compressed state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an integrated circuit device and its mounting structure and method, and more particularly to an integrated circuit device mounted on a printed circuit board and its mounting structure and method.

[0002]

2. Description of the Related Art Conventionally, there are various structures for mounting a semiconductor integrated circuit device (hereinafter referred to as an IC) on a printed circuit board (hereinafter referred to as a PWB), depending on the shape of the IC. There is one disclosed in Japanese Unexamined Patent Publication No. Sho 62-15884.

FIGS. 3 to 5 are cross-sectional views showing a conventional IC mounting structure. FIG. 3 shows PGA (Pin Grid Ar).
3 is a cross-sectional view showing a structure in which the IC 10 of FIG. Plural pins 1 implanted on the lower surface of IC 10
3 is inserted into a through hole 14 provided in the PWB 5, and the pin 13 and the through hole 14 are joined by solder 6. FIG. 4 shows a QFP (Quad Flat).
FIG. 2 is a cross-sectional view showing a structure in which a package (IC) 11 is mounted on a PWB 5. Leads 15 provided around the IC 11 are mounted on pads 4 provided on the PWB 5 and joined to each other by solder 6.

[0005] The IC 12 shown in FIG. 5 has a spring portion 18 formed by bending the tip of a lead 17 provided on the periphery.
Connect the spring portion 18 of the lead 17 to the through hole 14 of the PWB 5
Then, the spring 17 presses the inner wall of the through hole 14 to prevent the lead 17 from coming out of the through hole 14, and the IC 12 is mounted without using solder.

In addition to the above, there is a BGA connection structure in which metal balls arranged on the lower surface of the IC are mounted on PWB pads and soldered to each other as a conventional IC mounting structure.

[0006]

The first problem is that FIG.
In addition, in the conventional mounting structure of the IC shown in FIG. 4, it is very difficult to remove the IC from the PWB when the IC needs to be replaced or repaired.

[0007] The reason is that it is necessary to melt the solder connecting the IC to the PWB.

A second problem is that in the conventional IC mounting structure shown in FIGS. 3 and 4, when the IC is removed from the PWB, the PWB and peripheral components are often adversely affected.

The reason is that when the IC is removed from the PWB, the solder must be heated to melt the solder, and thermal stress is applied to the PWB and peripheral components. For example, in a BGA connection structure, it is necessary to heat even the gap between the IC and the PWB, which has a great adverse effect on the PWB and the like.

A third problem is that the conventional IC mounting structure shown in FIG. 5 increases the manufacturing cost of the IC.

The reason is that all the leads 17 of the IC 12
This is because the spring portion 18 must be formed at the bottom.

An object of the present invention is to provide an IC that does not require soldering for mounting on a PWB and that can be easily attached to and detached from the PWB.

[0013]

The IC of the present invention (2 in FIG. 1)
0) is a lock pin (2 in FIG. 1) provided on a substrate (21 in FIG. 1) and having an enlarged portion (22 in FIG. 1) that can be elastically deformed so as to be thin at the tip, and And a terminal (1 in FIG. 1) provided. Preferably, the terminal can be compressed by elasticity.

In the method of mounting an IC on a PWB according to the present invention, the lock pin (2 in FIG. 2) is inserted into a hole (3 in FIG. 2) provided in a PWB (5 in FIG. 2), and the substrate is mounted on the PWB. PW
B and press the terminal (1 in FIG. 2) to the PW
It is characterized in that it is pressed against the pad (4 in FIG. 2) on B and the enlarged part (22 in FIG. 2) penetrates through the hole.

According to the mounting structure of the IC of the present invention on a PWB, the lock pin (2 in FIG. 2) is inserted into a hole (3 in FIG. 2) provided in the PWB (5 in FIG. 2). (2 in FIG. 2)
2) penetrates the hole, and the terminal (1 in FIG. 2) is in pressure contact with a pad (4 in FIG. 2) on the PWB.

[0016]

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a side view of an IC 20 according to an embodiment of the present invention. Lock pins 2 are planted at four corners on the lower surface of the substrate 21 of the IC 20, and the terminals 1 are arranged in a matrix over substantially the entire lower surface of the substrate 21.

The lock pin 2 has an enlarged portion 22 at the tip end, and is substantially cylindrical except for the enlarged portion 22, and is made of an elastic metal or the like. The enlarged part 22 forms a part of a substantially spherical surface,
If the outer surface is pressed by providing a plurality of slits in the axial direction of the lock pin 2, the lock pin 2 is elastically deformed so as to have a smaller diameter.

The terminal 1 has a built-in coil spring having a cylindrical outer periphery having a distal end surface, and is compressed by elasticity when the distal end surface is pressed. The terminal 1 is made of metal and is connected to an electronic circuit provided on the substrate 21.

FIG. 2 is a side sectional view showing a state where the IC 20 of FIG. 1 is mounted on the PWB 5. The lock pin 2 is inserted into the mounting hole 3 provided in the PWB 5, and the board 21 is
5, the terminal 1 is pressed against the pad 4 on the PWB 5 to make it in a compressed state. The diameter of the mounting hole 3 is substantially the same as that of the lock pin 2 and smaller than the diameter of the enlarged portion 22. When the lock pin 2 is inserted into the mounting hole 3, the enlarged portion 22 becomes thinner due to elastic deformation. Locking is performed, and the IC 20 is fixed to the PWB 5 with the terminal 1 compressed.

The lock pin 2 is formed by such an enlarged portion 22.
When the terminal 1 is locked in the mounting hole 3, the terminal 1 is pressed against the pad 4 and is electrically connected to a circuit provided in the PWB 5 via the pad 4.

When removing the IC 20 from the PWB 5,
Grasping the substrate 21 and expanding the elastic part 2 against the elastic force of the expanding part 22
2 is thinly deformed and the lock pin 2 is pulled out from the mounting hole 3.

The lock pin 2 is connected to the circuit of the board 21 and the mounting hole 3 is formed as a through-hole connected to the circuit of the PWB 5, so that the circuit between the board 21 and the PWB 5 May be electrically connected.

Further, the lock pin 2 is not limited to the above-described shape, but may be, for example, a pair of thin flat plate springs whose distal ends are curved outward.

The terminal 1 is not limited to the one described above. For example, a terminal in which a bent thin plate spring is fixed to the PWB 5 and its tip is elastically bent, a terminal in which the coil spring is fixed to the PWB 5 as it is, Rubber having a property may be fixed to PWB5. Further, even if the elasticity or plasticity is not particularly large, such as a spring or rubber, a material having a little elasticity or plasticity, such as a solder bump, may be used as PWB5.
And may be pressed against the pad on the PWB 5 (without melting the solder bumps). However, when a terminal having low flexibility such as a solder bump is used as the terminal, it is necessary to accurately determine the flatness of the lower surface of the substrate and the upper surface of the PWB 5 and the height of the solder bump.

The number of lock pins is not limited to four at four corners on the lower surface of the IC substrate, and five or more or three or less lock pins may be provided at appropriate positions on the IC.

[0027]

The first effect is that the IC can be easily attached to and detached from the PWB, and the number of steps for attaching and detaching the IC when the IC needs to be replaced can be greatly reduced.

The reason is that the state in which the terminal of the IC is pressed against the pad of the PWB is held by inserting the lock pin into the hole of the PWB, so that solder is not used for mounting the IC and there is no need to melt the solder. Because.

The second advantage is that the IC shown in FIG.
It does not require much cost as C12.

The reason is that it is not necessary to provide springs on all the leads as in the case of the IC 12, and it is only necessary to provide an enormous portion which is elastically deformed only on the lock pin. As the terminals, solder bumps can be used, and even if the terminals have elasticity, they only need to be compressed, so that leaf springs or conductive rubber can be used, and the terminals can be manufactured at very low cost.

[Brief description of the drawings]

FIG. 1 is a side view of an IC 20 according to an embodiment of the present invention.

FIG. 2 is a side sectional view showing a mounting structure of the IC 20 shown in FIG. 1 on a PWB 5;

FIG. 3 is a side sectional view showing a mounting structure of a conventional IC 10 on a PWB 5.

FIG. 4 is a side sectional view showing a mounting structure of another conventional IC 11 on a PWB 5;

FIG. 5 is a side sectional view showing a conventional mounting structure of still another IC 12 on a PWB 5;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Terminal 2 Lock pin 3 Hole 4 Pad 5 PWB 6 Solder 10 IC 11 IC 12 IC 13 Pin 14 Through hole 15 Lead 17 Lead 18 Spring part 20 IC 21 Substrate 22 Enlarged part

Claims (4)

[Claims] 1. An integrated circuit device, comprising: a lock pin provided on a substrate and having a bulging portion capable of being elastically deformed so as to be thin at a tip, and a terminal provided on the substrate. 2. The integrated circuit device according to claim 1, wherein said terminals can be compressed by elasticity. 3. Inserting the lock pin into a hole provided in a printed circuit board, pressing the board toward the printed circuit board, pressing the terminal against a pad on the printed circuit board, and moving the enlarged portion from the hole. 3. The method for mounting an integrated circuit device on a printed circuit board according to claim 1, wherein the integrated circuit device is penetrated. 4. The device according to claim 1, wherein said lock pin is inserted into a hole provided in a printed circuit board, said enlarged portion penetrates said hole, and said terminal is pressed against a pad on said printed circuit board. 3. A mounting structure of the integrated circuit device according to 1 or 2 on a printed circuit board.