Patent · US Active

Sensing circuit for use with capacitive touch panel

US8421774B2 · kind B2 · utility

3Cited by
3References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 23, 2010
Grant dateApr 16, 2013
Priority date
Expiry dateSep 8, 2031

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F3/044
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A sensing circuit of a capacitive touch panel includes a first switch, a second switch, a third switch, a feedback capacitor, a fourth switch and an operation amplifier. The first switch and the second switch have respective first ends connected with a receiving electrode. The third switch has a first end connected with a second end of the first switch. The feedback capacitor has a first end connected with the second end of the first switch. The fourth switch has a first end connected with a second end of the feedback capacitor. The operation amplifier has a positive input terminal connected with a ground terminal, a negative input terminal connected with the fourth switch, and an output terminal connected with the second, third and fourth switches. These switches are controlled during a driving cycle of the driving signal, so that an output voltage is outputted from the operation amplifier.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.