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:
Apr. 04, 2006
Filed:
Nov. 06, 2003
Eugen Popescu, Santee, CA (US);
Herbert Otto Fredrickson, Chula Vista, CA (US);
Eugen Popescu, Santee, CA (US);
Herbert Otto Fredrickson, Chula Vista, CA (US);
Crydom Technologies, George Town, KY;
Abstract
A lead frame for use in solid state relays has a teardrop shaped frame. The frame has a small rounded portion connected to a large rounded portion. A power semiconductor is mounted in the large rounded portion. The teardrop shape eliminates sharp corners found in rectangular frames and allows heat to dissipate radially in all directions. More metal in close proximity to the power semiconductor, maintaining a lower aspect ratio of length to width, allows the semiconductor to run cooler at any given load. Several vent holes are located in the small rounded portion, which act as exhaust ports for the fumes generated in the heating stage of the solder re-flow, increasing solder coverage and improving reliability. The life of solder junctions utilizing the teardrop shaped lead frame which are subjected to temperature cycling while under load is increased, thus extending the life of the solid state relay.