Interference-insensitive capacitive displacement sensing
US10254134B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 27, 2017 |
| Grant date | Apr 9, 2019 |
| Priority date | — |
| Expiry date | Aug 30, 2037 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R27/2605
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An excitation signal is produced on a plate of an unknown capacitor and on a plate of a known capacitor. The excitation signal is amplified over time to produce a first output signal, with gain that is proportional to capacitance of the unknown capacitor. The excitation signal is also amplified over time to produce a second output signal, with gain that is proportional to capacitance of the known capacitor. Capacitance of the unknown capacitor is computed using a mathematical function of the first and second output signals and the capacitance of the known capacitor, while being insensitive to amplitude of the excitation signal. Other embodiments are also described and claimed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.