Frequency hopping for a capacitive touch screen controller
US11604541B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Aug 31, 2020 |
| Grant date | Mar 14, 2023 |
| Priority date | — |
| Expiry date | Jun 22, 2041 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2203/04105
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A circuit includes a force driver to apply a force signal to a force node associated with a mutual capacitance to be sensed, and a charge to voltage converter having an input coupled to receive a sense signal from a sense node associated with the mutual capacitance to be sensed. The charge to voltage converter includes an integrator circuit to integrate the sense signal to sense the mutual capacitance, an input switch between the input of the charge to voltage converter and an input of the integrator circuit, and a reset switch between an output of the integrator circuit and the input of the integrator circuit. A control circuit controls generation of the force signal to alternate between at least two different frequencies and generates, for each half cycle of the force signal, a first signal for closing the input switch and a second signal for closing the reset switch.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.