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. 26, 2019
Filed:
Oct. 23, 2017
Raydium Semiconductor Corporation, Hsinchu, TW;
Chih-Hsiung Chen, Hsinchu County, TW;
Yu-Chin Hsu, Hsinchu, TW;
Meng-Yi Chen, Kaohsiung, TW;
Chih Yuan, New Taipei, TW;
Raydium Semiconductor Corporation, Hsinchu County, TW;
Abstract
A self-capacitive touch sensing circuit including an operational amplifier, an internal capacitor, a first switch and a second switch is disclosed. A first input terminal and a second input terminal of operational amplifier are coupled to a capacitor and ground respectively and an output terminal of operational amplifier outputs an output voltage. The internal capacitor is coupled between the output terminal and first input terminal of operational amplifier. One terminal of first switch is coupled to a first external charging voltage and another terminal of first switch is coupled between the capacitor and the first input terminal. The first external charging voltage is higher than the second external charging voltage. The first switch and second switch are switched according to a specific order, so that the first external charging voltage or second external charging voltage will charge the capacitor.