JPH03241766A - Lsi package - Google Patents

Abstract

PURPOSE:To eliminate pads for remodeling on a printed board by a method wherein conducting parts corresponding to respective external connection pins are provided on the upper surface of a package and the external connection pins penetrate the package and the conducting parts are exposed on the upper surface of the package. CONSTITUTION:External connection pins 11 are connected to through-holes provided in patterns 13 on a printed board 12. The board 12 is mounted on a case 14 and covered with a cover 15. The board 12 is exposed from the case 14 with the patterns 13 and the upper pat of the LSI package can be connected to the patterns 13. Thus, by exposing the conducting parts corresponding to the respective external connection pins 11 on the upper surface of the LSI package, pads for remodeling on the printed board 12 can be eliminated.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to an LSI package.

[Conventional technology]

Conventionally, when an LSI package is mounted on a printed wiring board, when corrections are made due to design errors such as wiring patterns on the board, modification pads are prepared in advance on the board for each external connection pin of the LSI package. Wires may be connected between them.

On the other hand, in order to check whether the external connection pins of the LSI package are securely soldered on the board, a through path is provided inside the LSI from the input pins to the output pins among the external connection pins, and the pins are connected to the input pins. Sometimes a method is used to verify that the pattern that was created can be applied to the pin as is. Also, from the back side of the LSI package mounting surface of the board, probes that correspond one-to-one to the net are set up.
An in-circuit test method is sometimes used in which a test pattern is applied to a probe corresponding to an input pin and the pattern applied to the probe corresponding to an output pin is verified.

[Problem to be solved by the invention]

As mentioned above, in conventional LSI packages, providing a through path just to check whether external connection pins are properly soldered on the board requires a considerable amount of hardware, including selectors. This is difficult in reality. Furthermore, when LSI packages are mounted on both sides of the board, it is extremely difficult to set up a probe from the back side of the LSI package mounting surface. Furthermore, in recent years, as the number of LSI packages mounted on a board has increased and the distance between mounted LSI packages has become narrower, it has become difficult to provide the above-mentioned conventional modification pads on the board. There is.

[Means to solve the problem]

The LSI package of the present invention is characterized in that a conductive part is provided on the top surface of the package in one-to-one correspondence with the external connection pin, or the external connection pin penetrates the package and the conductive part is exposed on the top surface. It is composed of

〔Example〕

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

FIGS. 1(a) and 1(b) are a plan view and a side view, respectively, of an embodiment of the present invention. In FIG. 1, a substrate 1
The external connection pin 11 is connected to the through hole provided in the pattern 13 on the top 2, and the board 12 is mounted on the case 13 and covered by the cover 15, but the board 12 and the pattern 13 are connected to the outside of the case 14. being exposed,
It is possible to connect to the pattern from the top of the LSI package.

FIGS. 2(a) and 2(b) are a plan view and a side view, respectively, of another embodiment of the invention. In FIG. 2, an external connection pin 21 is connected to a through hole provided in a pattern 23 on a substrate 22, and a pad 24 provided on the external connection pin 21 is exposed on the upper surface of a case 25 on which the substrate 22 is mounted. ing. Note that an LSI chip 28 is mounted on the case 25 and connected to the pattern 23 by a bonding wire 27.

〔Effect of the invention〕

As explained above, the present invention has conductive parts exposed on the top surface of the LSI package in one-to-one correspondence with external connection pins, so there is no need for pads for modification on the printed circuit board, and Soldering between the connection pins and the printed circuit board has the effect of facilitating inspection for defects.

[Brief explanation of drawings]

FIGS. 1(a) and (b) are a plan view and a side view, respectively, of one embodiment of the present invention, and FIGS. 2(a) and (b) are a plan view and a side view, respectively, of another embodiment of the present invention. It is. 11.21... External connection pin, 12.22... Board, 13.23... Pattern, 14.25... Case, 15.2E! ...Cover, 18.28...Bonding wire, 24...Pad.

Claims (1)

[Claims] 1. In an LSI package, one to one external connection pin
An LSI package characterized in that a conductive portion corresponding to the above is provided on the upper surface of the package. 2. An LSI package characterized in that an external connection pin passes through the package and a conductive portion is exposed on the top surface.