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:
Jul. 08, 1986
Filed:
Aug. 15, 1978
Daniel D Culmer, Sunnyvale, CA (US);
Robert A Cometta, San Jose, CA (US);
National Semiconductor Corporation, Santa Clara, CA (US);
Abstract
An integrated circuit includes a plurality of circuit elements interconnected to operate as a circuit and formed in a common semiconductor substrate. The substrate is mounted on a supporting package, resulting in a mechanical stress in the substrate which is symmetrical about at least one given axis. At least the circuit elements with operating characteristics which are altered by the mechanical stress and which have a critical matching or ratio relationship are arranged symmetrically about the stress axis of symmetry. In a preferred form, the integrated circuit is a linear circuit, such as an operational amplifier employing junction field effect transistors (JFETs) for its input stage and bipolar transistors for its amplifier stage. Providing device symmetry about an axis of mechanical stress symmetry enables shifts in input offset voltage for such operational amplifiers to be reduced up to a factor of about 10.