Mitsubishi Denki Kabushiki Kaisha

Satoshi Ookyuu

Akihiro Goto

Yoshiharu Takahashi

Hirokazu Taki

Takashi Arita

Takao Takahashi

Yasuhito Suzuki

Hirochika Kawaguchi

The primary objective of the present invention is to select a connecting combination of the plurality of solder ball connection pads and the plurality of wire bond pads, and generate an optimum wiring candidate. For this objective, the wiring pattern generation unit generates a wiring pattern as the information for specifying an in-area wiring route to be wired in each row and an in-area wiring route to be connected to the next row among the solder ball connection pad area closer to the wire bond pad area, based on the design conditions of the wiring route stored in the design condition memory. Then, the wiring plan generation unit generates a wiring plan laying out the plurality of wiring routes by combining the wiring patterns generated for each row, and the wiring rule check unit selects some of the generated wiring plans suited for the wiring rules and generates the plurality of wiring candidates. Furthermore, the quality rating unit rates the generated wiring candidates and selects the best wiring candidate.

Circuit wiring system circuit wiring method semi-conductor package and semi-conductor package substrate

To determine leadframe tip positions, a circular arc portion where leadframe tips are to be arranged is determined so as to be opposed to each of the four corners of a die pad by performing a search. Then, straight line portions are set so as to extend from the circular arc portion and to be opposed to the die pad sidelines. The shape of each leadframe tip on the circular arc portion is defined as a region that is sectioned by two concentric circles and two radial rays extending from the center of the concentric circles. The division between the circular arc portion and straight line portions and the setting of the center of the circular arc portion are performed automatically. The leadframe tip width and interval are determined independently of each other.

Designing method of leadframe tip arrangement

First, a reference point on a die pad and a leadframe tip arrangement line are set. A plurality of isosceles triangles having the same base length are set so that their apices are located at the reference point. A given number of isosceles triangles are arranged inside the leadframe tip arrangement line by adjusting the base length. The base length of the isosceles triangles is employed as a uniform lead pitch, and a uniform lead width is then determined. The base length of the isosceles triangles is calculated by using the successive bisection algorithm.

Leadframe tip arrangement designing method

A designing method calculates leadframe tip arrangement. The method comprises the steps of setting a leadframe tip arrangement region opposed to a die pad sideline of a leadframe, setting a leadframe tip arrangement line in the leadframe arrangement region, and arranging a predetermined number of leadframe tips on the leadframe tip arrangement line at proper intervals. The method allows for the independent calculation of various parameters.

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Hyogo, Japan

Satoshi Ookyuu