Capacitive pick-off circuit
US4165483A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 31, 1978 |
| Grant date | Aug 21, 1979 |
| Priority date | — |
| Expiry date | Jan 31, 1998 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01P15/125
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An improved capacitive pick-off circuit is provided by utilizing a reference current generator to apply a square wave to a pick-off capacitor and the resulting voltage across the capacitor is then applied to a fixed capacitor. The resulting fixed capacitor current then provides a measure of the capacitance of the pick-off capacitor. A differential capacitive pick-off circuit is provided by applying the reference current to each pick-off capacitor and providing a fixed capacitor for each of the pick-off capacitors. The resulting fixed capacitor currents are combined and the resulting differential current is used as a measure of the difference in capacitance or the difference in the gaps between the plates of the capacitors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.