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. 16, 1985
Filed:
Jul. 02, 1984
Gurnam Singh, Riverside, CA (US);
ITT Corporation, New York, NY (US);
Abstract
Differential and static pressure transducers are provided with piezoresistive elements connected in Wheatstone bridges on the 100 surface of a silicon chip over a diaphragm etched into the chip from the back. A thin disk diaphragm is used for differential pressure (DP) and a thicker annular diaphragm around the disk diaphragm is used for static pressure (SP) measurements. Two of the elements opposite each other in each bridge are produced along one crystallographic direction (110), and the other two are produced along an orthogonal crystallographic direction (110). Extra elements are produced for each pair to permit selection of a more closely matched set of four elements. A plurality of DP diaphragms with different diameters and respective bridges are provided along with a multiplexer for selecting a DP bridge in order to provide different ranges of sensitivity for the differential pressure measurements.