Reducing noise in a capacitive sensor with a pulse density modulator
US10718801B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 20, 2018 |
| Grant date | Jul 21, 2020 |
| Priority date | — |
| Expiry date | May 30, 2038 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R3/002
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method for measuring a capacitive sensor output may include applying an excitation signal to a capacitor of the capacitive sensor which causes generation of a modulated signal from a baseband signal, wherein the excitation signal is of a carrier frequency which is higher than frequency content of the baseband signal, demodulating the modulated signal to generate an intermediate signal representative of a capacitance of the capacitor wherein the demodulating is based, at least in part, on the excitation signal, converting the intermediate signal into a pulse-density modulated output signal with a pulse-density modulator, and shaping a noise transfer function of the pulse-density modulator to have an approximate zero at the carrier frequency.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.