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. 17, 2015
Filed:
Jan. 30, 2013
Guo Wen Wei, San Jose, CA (US);
Tom W. Kwan, Cupertino, CA (US);
Guo Wen Wei, San Jose, CA (US);
Tom W. Kwan, Cupertino, CA (US);
Broadcom Corporation, Irvine, CA (US);
Abstract
An interference tolerant capacitive touch sensor readout circuit having improved power and area efficiency is disclosed. Interference rejection for the capacitive touch sensing system is realized by transferring charge between a capacitive touch sensor and the readout circuit at frequencies outside bands where a level of interference is unacceptable. Improved power and area efficient come from the simplicity of the readout circuit which comprises a switched-capacitor integrator, a comparator, a digital accumulator and number of switches for driving a touch sensor and a capacitive feedback loop. The readout circuit is capable of interfacing with both self and mutual capacitance sensor to achieve compatibility with a larger collection of sensors and provides additional sensing and diagnostic functionalities.