Capacitive sensor including compensation for phase shift
US11119138B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 2, 2020 |
| Grant date | Sep 14, 2021 |
| Priority date | — |
| Expiry date | Apr 2, 2040 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R27/2605
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method may include applying an excitation signal to a capacitor of the capacitive sensor which causes generation of a modulated signal from an input signal indicative of a variance in a capacitance of the capacitor, detecting the modulated signal with a detector to generate a detected modulated signal that has a phase shift relative to the excitation signal, demodulating the detected modulated signal into an in-phase component and a quadrature component using a reference signal, nullifying the quadrature component by setting a phase of the reference signal relative to the excitation signal to compensate for the phase shift, and outputting the in-phase component as an unmodulated output signal representative of the capacitance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.