Readout circuit for touch panel
US7863966B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 17, 2009 |
| Grant date | Jan 4, 2011 |
| Priority date | — |
| Expiry date | Sep 17, 2029 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F3/04182
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A readout circuit for touch panel includes first and second switches, an operational amplifier (OP-AMP), a feedback capacitor, a comparison unit, and a counter. A first input terminal and an output terminal of the OP-AMP are respectively coupled to a second terminal of the first switch and an input terminal of the comparison unit. A second input terminal of the OP-AMP receives a reference voltage. Two terminals of the feedback capacitor and the second switch are respectively coupled to the first input terminal and the output terminal of the OP-AMP. The comparison unit selects first or second threshold voltages to compare with an output of the OP-AMP according to a output of the comparison unit. An input terminal of the counter receives the output of the comparison unit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.