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:
Dec. 19, 2017
Filed:
Nov. 03, 2014
Qualcomm Incorporated, San Diego, CA (US);
Ozan E. Erdogan, Saratoga, CA (US);
Guozhong Shen, San Jose, CA (US);
Rajesh Anantharaman, San Jose, CA (US);
Ajay Taparia, San Jose, CA (US);
Behrooz Javid, Irvine, CA (US);
Syed T. Mahmud, Dublin, CA (US);
Rahim F. Chowdhury, Saratoga, CA (US);
QUALCOMM Incorporated, San Diego, CA (US);
Abstract
An analog front end circuit utilizes coherent detection within a capacitance measurement application. The analog front end circuit uses coherent detection to measure capacitance of a touch screen display. An analog excitation signal is modulated by a capacitor to be measured. The modulated signal is synchronously demodulated using a correlator, which includes a discrete mixer and a discrete integrator. The excitation signal is also input to the mixer such that the modulated signal is multiplied by the excitation signal. The excitation signal is an analog signal having a sine wave function or other waveform.