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:
Mar. 12, 2013
Filed:
Jul. 15, 2011
Vitali Souchkov, Walnut Creek, CA (US);
Vitali Souchkov, Walnut Creek, CA (US);
Pixart Imaging, Inc., Hsin-Chu, TW;
Abstract
Various embodiments of capacitive touchscreen driving and sensing circuits are disclosed, where during a first phase the mutual capacitance between a given drive electrode and a given sense electrode is charged up to a first charge value corresponding substantially to a drive voltage times the mutual capacitance. During a second phase the charge storage capacitor is charged up to a value corresponding approximately to a difference in touchscreen capacitance network charges occurring during the first and second phases. The first and second phases do not overlap in time. Dark frame signals may also be acquired from the touchscreen to calibrate differences in touchscreen capacitance network charges.