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:
Aug. 13, 2002
Filed:
Dec. 20, 1999
Keith W. Kawate, North Attleboro, MA (US);
David L. Corkum, Attleboro, MA (US);
Thomas R. Maher, Rehoboth, MA (US);
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
An in-range fault detection system for a full wheatstone bridge element ( ) having piezoresistive elements (R , R , R , R ) has bridge outputs (INP, INM) connected to measuring means in the form of a first circuit portion ( ) to provide a common mode voltage (V ). A second circuit portion ( ) is used to provide a centering voltage (C*V ) equal to the common mode voltage at the time of sensor calibration and a third circuit portion ( ) is used to provide a small window voltage (W*V ) which is a fraction of bridge voltage. The value (W*V ) is subtracted from (C*V ) at a first summing circuit (SUM ) and added to (C*V ) at a second summing circuit (SUM ) and the results are each compared to the common mode voltage by comparators (Q , Q ) which are then determined to be within or without a window of valid values by an OR gate (Q ).