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:
May. 25, 1993
Filed:
Jan. 31, 1990
Applicant:
Inventor:
Timo Saarnimo, Salo, FI;
Assignee:
Nokia Mobile Phones Ltd., Salo, FI;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L / ; H02B / ; H05K / ; H01P / ;
U.S. Cl.
CPC ...
257712 ; 257713 ; 257718 ; 257719 ; 333246 ; 333247 ; 361380 ; 361381 ; 361386 ; 361389 ;
Abstract
A cooling structure for a high frequency power transistor is mounted on a circuit board where heat generated by the transistor is conducted from the semiconductor material through the collector conductor. A metal piece, which is larger than the collector conductor and sized to the requirements of heat removal through the collector conductor, contacts the collector conductor or an extension. The metal piece is solidly attached to a conductor strip formed on the circuit board. Heat is dissipated from the exposed surface of the metal piece to the ambient air and by conduction to the circuit board.