Oversampled high signal to noise ratio analog front end for touch screen controllers
US11294504B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 5, 2019 |
| Grant date | Apr 5, 2022 |
| Priority date | — |
| Expiry date | Jan 14, 2040 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F3/044
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A touch screen controller includes an input stage configured to receive and condition a touch output from a touch matrix to produce a touch signal. An accumulation stage is configured to receive the touch signal and accumulate the touch signal to produce an accumulated output. The accumulated output is digitized by an analog to digital converter to produce a touch strength value. A given amount of charge is subtracted from or added to accumulated output during a next accumulation if the touch strength value is greater than an upper threshold or less than a lower threshold. This avoids saturation of components in the touch screen controller and therefore increases the signal to noise ratio.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.