JPH0815196B2 - Lead frame for integrated circuit device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a structure of a lead frame for an integrated circuit device.

[Conventional technology]

As shown in FIG. 4, a conventional lead frame for an integrated circuit device has a plurality of leads 53 which are arranged in parallel in the same pitch with their free ends being close to the mounting tabs 52 of the integrated circuit chip 51.
However, outside the sealing resin mold region 54, they are connected by a connecting piece 55 and supported by a pair of parallel frame bodies. In the integrated circuit device using the lead frame 60 of the conventional example, the integrated circuit chip 51 is placed on the tab 52, wire bonding connection (not shown) is made with each lead 53, and the resin mold is used for sealing. Here, the resin 56 that has flowed to the connecting piece 55 and is solidified is pulled out by a punch such as a press die, and then the connecting piece 55 is cut into individual lead terminals.

[Problems to be solved by the invention]

However, according to the structure of the conventional lead frame for an integrated circuit as described above, the leads having the same shape are arranged in the same pitch, and the unnecessary lead is deleted when manufacturing a model in which the lead is unnecessary. It is necessary to manufacture a new press die etc. for removing the sealing resin burr that has flowed to the lead frame and the connecting piece of the lead frame, which increases the equipment cost and the number of manufacturing days. Had.

Therefore, the present invention solves such a problem, and an object of the present invention is to improve the number of unnecessary leads by simply changing the lead frame without newly producing a press die and using the standard type process. By providing a flowable lead frame, it is an object to provide an integrated circuit device at a low cost and with a short lead time. Another object of the present invention is to provide an integrated circuit device capable of preventing the occurrence of resin burr that occurs at the center of the side forming the resin mold region during resin molding and preventing the lead frame from being deformed. To provide a lead frame.

[Means for solving problems]

The lead frame for an integrated circuit device of the present invention comprises a pair of frame bodies, a tab provided between the frame bodies for mounting an integrated circuit chip, and at least one free end of which is adjacent to the tab. Two or more first leads, at least one or more second leads, a connecting piece that connects the first lead and the second lead and is supported by the frame body, and the second An X-shaped support piece that connects the other end of the lead to the closest frame body, and the free end of the second lead seals the first lead and the integrated circuit chip. Is close to the central portion of at least one side forming the resin mold area, and
The X-shaped support piece, which is provided at a position that does not enter the resin mold region, bypasses the other free end of the first lead.

Note that, hereinafter, the second lead is referred to as "cut lead".

[Work]

According to the above configuration of the present invention, since the shape outside the resin mold region is almost the same, the press dies may be the same and the resin can be removed. Further, since the unnecessary lead has its free end outside the resin mold area or on the line of the resin mold area, even if cutting is performed after the resin molding, the integrated circuit device is not affected at all.

〔Example〕

An embodiment of the present invention will be described in detail with reference to FIG. FIG. 1 is an example of a case where four leads of a DIP-8PIN lead frame are unnecessary and is a plan view thereof. In this example, a pair of frame bodies 1.6 parallel to each other, a tab 2 for mounting an integrated circuit chip provided between the frame bodies 1 and 6, and the tab 2 directly on the frame bodies 1 and 6. Alternatively, the tab leads 3 and 8 for indirectly supporting and connecting to the tab 2, the lead 4 in which one free end of the tab lead 2 is in close proximity, and the integrated circuit chip mounted on the tab 2 (not shown in the drawing) A lead 5 having its free end outside the resin mold region 10 close to the resin mold region 10 for encapsulating etc., and the leads 4 and 5
Connecting pieces 7 that connect the two to support the frames 1 and 6 respectively.
And a support piece 9 which connects the leads 5 to each other and bypasses the other free end of the lead 4 to support the frames 1 and 6
It consists of

Here, the lead 5 is originally an unnecessary lead, and as shown in FIG.
As in the structure shown in FIG. 3, the lead 14 may be removed at the time of molding the lead frame, and the necessary leads 14 may be connected by the connecting piece 17 that has a function of preventing the flow of the resin mold.
Resin burrs 12 that occur during resin molding during processing
When the standard DIP-8PIN press-type punch shape and structure 16 are used when the (shaded) portion is removed, the resin burr in the portion shown by the mesh pattern in the figure (that is, the original position of the lead 5) remains. Therefore, the lead 5 is provided at the position where the lead exists, outside the mold region 10 to leave a gap of about 0 to 0.2 mm, so that resin burr does not occur. Further, the support piece 9 prevents the lead 5 from being unable to be held as a single piece in the cutting work of the connecting piece performed after the resin burr is removed, and is connected to the frame body 1.6 to enable simultaneous processing. is there.

This example has been described by taking the DIP-8PIN as an example.
The same application is possible in a resin mold type integrated circuit device using a lead frame such as a PIN or SIP-6PIN.

〔The invention's effect〕

According to the lead frame having the configuration of the present invention described above,
It is possible to manufacture different types of integrated circuit devices by changing the shape of the lead frame without changing the equipment such as the press type, and without changing the processing process, shortening the lead time and reducing the equipment cost. In addition, an inexpensive integrated circuit device can be provided in a short time.
In addition, it is particularly effective in manufacturing a large number of small quantities.

Furthermore, since the free end of the lead 5 which is originally unnecessary is arranged in the central part of the side forming the resin mold region, it is possible to prevent the occurrence of resin burr in the central part of the side of the resin mold to which the highest resin pressure is applied. It is possible to prevent the lead frame from being deformed.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of a lead frame for an integrated circuit device of the present invention. 1,6 …… Frame, 2 …… Integrated circuit chip mounting tabs, 3,8…
... tab lead, 4 ... lead, 5 ... essentially unnecessary lead, 7 ... connecting piece, 9 ... support, 10 ... resin mold area, Figs. 2 and 3 are for an integrated circuit device of the present invention. The figure for demonstrating the Example of a lead frame. 12 …… Resin burr, 14 …… Lead, 15 …… Unnecessary lead, 16 …… Press type punch shape, Fig. 4 is a plan view showing a conventional lead frame for an integrated circuit device.

Claims (1)

[Claims] 1. A pair of frame bodies, tabs provided between the frame bodies for mounting an integrated circuit chip, and at least one free end of which is adjacent to the tabs.
Two or more first leads, at least one or more second leads, a connecting piece that connects the first lead and the second lead and is supported by the frame body, and the second An X-shaped support piece that connects the other end of the lead to the closest frame body, and the free end of the second lead seals the first lead and the integrated circuit chip. The X-shaped support piece is provided at a position close to the central portion of at least one side forming the resin mold region and does not enter the resin mold region, and the X-shaped support piece is the other free end of the first lead. A lead frame for an integrated circuit device, characterized in that the lead frame is bypassed.