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:
Nov. 10, 2015
Filed:
Mar. 15, 2013
Synaptics Incorporated, Santa Clara, CA (US);
Farzaneh Shahrokhi, San Jose, CA (US);
Adam Schwartz, Redwood City, CA (US);
Shahrooz Shahparnia, Campbell, CA (US);
Joseph Kurth Reynolds, Alviso, CA (US);
Tracy Scott Dattalo, Santa Clara, CA (US);
Synaptics Incorporated, San Jose, CA (US);
Abstract
A differential amplifier has an output and differential first and second inputs. A switch disposed between a sensor electrode and the second input is opened to initiate a reset phase where the sensor electrode and the differential amplifier are decoupled. A feedback capacitance disposed between the second input and the output is reset to a first level of charge. The switch is closed to initiate a measurement phase where the second input and sensor electrode are coupled. In the measurement phase: charge is balanced between the sensor electrode and the feedback capacitance such that a sensor electrode voltage equals a voltage of the first input equals a voltage of the second input, and the sensor electrode is charged; and the differential amplifier is utilized to integrate charge on the sensor electrode, such that an absolute capacitance corresponding to a coupling between the sensor electrode and an input object is measured.