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. 09, 2000
Filed:
Dec. 11, 1998
Martin Ridgway Handforth, Kanata, CA;
Donald G Paterson, Raleigh, NC (US);
Sudhir Majmudar, Ottawa, CA;
Michael H Daniels, Kanata, CA;
Nortel Networks Corporation, Montreal, CA;
Abstract
A line circuit module is disclosed which comprises effectively all of the required circuitry for a line card apart from mechanical components such as relays and edge card connectors. The module includes a small ceramic substrate 2.0 inches by 0.825 inches on to which surface mount components which include a heat sensitive integrated circuit and a field effect transistor are mounted to one side and thick film components which include two battery feed resistors are printed on an opposite side. Various innovative techniques are disclosed which significantly reduce compromising component thermal interactions. Heat concerns from using a small thermally conductive substrate have been managed through advantageous use of printed battery feed resistor layouts which provide for larger portions of heat to be dissipated in resistor portions removed from a heat sensitive integrated circuit than resistor portions adjacent to the heat sensitive integrated circuit. Advantageous placement of feed resistor trim links to further manage heat dissipation are also disclosed. A line card which advantageously includes the line module is disclosed.