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. 05, 2002
Filed:
Sep. 05, 2000
Steven P. Callicott, Colorado Springs, CO (US);
Billy B. Duncan, Colorado Springs, CO (US);
William K. Petty, Colorado Springs, CO (US);
Mark S. Snyder, Colorado Springs, CO (US);
LSI Logic Corporation, Milpitas, CA (US);
Abstract
An apparatus detects the approach and touch-down of an object relative to a sensor panel. The apparatus includes a digital filter for determining a first derivative of a current flow in the sensor panel and a controller determines when the first derivative reaches a maximum. In a preferred embodiment, a magnitude for current flow in a plurality of corners of the sensor panel is determined by the controller. These magnitudes are then summed to determine a current flow from which the first derivative is computed. The current flow is analyzed by the controller to determine when an object is approaching the sensor panel, has contacted the sensor panel, and is withdrawn from the sensor panel. Thresholds are used to avoid false detection of approaching objects.