The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 26, 2002
Filed:
Jan. 09, 2002
Satoshi Hirakawa, Hitachinaka, JP;
Toshiaki Kaminaga, Naka-machi, JP;
Ryoichi Kobayashi, Tokai-mura, JP;
Noboru Sugiura, Mito, JP;
Other;
Abstract
Durability and lifetime of a resin sealed electronic device is improved by reducing thermal stresses acting on the power element and the parts mounting on the board. A power element of which the protective film on the power element is coated with a polyimide group resin at manufacturing the element is used, and a metallic heat sink of which the reverse side surface (portion of mounting on a board) is not plated is used. Further, a linear expansion coefficient of the molding resin is within a range of 3×10 /°C. to 17×10 /°C. The durability and the lifetime of the resin sealed electronic device is improved, because the thermal stresses are reduced by balancing linear expansion coefficients of the parts.