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:
Feb. 16, 1999
Filed:
Mar. 31, 1997
Applicant:
Inventors:
John R Figie, New Berlin, WI (US);
Gary Dan Dotson, Muskego, WI (US);
Assignee:
Allen-Bradley Company, LLC, Milwaukee, WI (US);
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G09G / ;
U.S. Cl.
CPC ...
345168 ; 345173 ; 341 22 ; 341 26 ;
Abstract
Driving circuitry for a switch matrix provides a reset voltage to all rows of the matrix in between scans to recharge switch capacitance. Column detection circuitry is disabled in between scans so that column driving circuitry may also `reset` the charge on capacitors reducing the scan time and/or allowing a greater number of switch elements, element size, or EMI suppressing capacitances. Pull-up resistors are supplemented or eliminated through the use of active current sourcing and sinking for the drivers.