Measuring circuit and measuring method for a capacitive touch-sensitive panel
US9727118B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 30, 2015 |
| Grant date | Aug 8, 2017 |
| Priority date | — |
| Expiry date | Jul 21, 2035 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F3/04166
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A measuring circuit connectable to a capacitive touch-sensitive panel, the panel including a plurality of sense electrodes and optionally a common guard electrode, adapted to measure variations in the instantaneous electric capacity of the sense electrodes in response to proximity to conductive bodies, wherein the sense electrodes are biased at a fixed voltage relative to the common guard electrode, the measuring circuit comprising: a power management integrated circuit comprising a voltage source generating a modulation voltage that is available at a guard terminal of the power management integrated circuit that is in electric connection with the guard electrode; one or more slave integrated circuits, each connected to a plurality of sense electrodes and comprising a Capacity-to-Digital converter or a plurality of Capacity-to-Digital converters that are operatively arranged for generating digital measure codes representing the instantaneous electric capacity of sense electrodes; a means for varying the frequency of the modulation voltage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.