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:
Dec. 16, 1997
Filed:
Jun. 20, 1996
Satoshi Hirakawa, Fukuoka, JP;
Haruo Takao, Fukuoka, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
It is an object to increase a breakdown voltage of a lead frame. A primary sealing resin (41) seals the upper main surface of a lead frame (3) and elements mounted thereon. A secondary sealing resin (21) coupling the lead frame (3) and a heat sink (51) passes through gaps of the lead frame (3) having pattern configuration to project on the upper main surface side of the lead frame (3). The primary sealing resin (41) is in close contact with the projections (62). The projections (62) enlarge the creeping distance along the interface between the primary sealing resin (41) and the secondary sealing resin (21) between parts of the lead frame (3) adjacent with gaps therebetween, so that the breakdown voltage between those parts is increased.