Circuit for acquisition of the capacitance or capacitance change of a capacitive circuit element or component
US6194903A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 2, 1997 |
| Grant date | Feb 27, 2001 |
| Priority date | — |
| Expiry date | Dec 2, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K2217/96075
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A circuit for acquisition of the capacitance or capacitance change of a capacitive circuit component with a clock generator (1), changeover contact (2) controlled by the clock generator (1), a storage capacitor (3), a voltage source (4), and an evaluation stage (5). An electrode of the capacitive circuit component is connected to the input (7) of the changeover contact (2), a first output (8) of the changeover contact (2) is connected to a first electrode of the storage capacitor (3), a first electrode of the storage capacitor (3) is connected, on the one hand, via a resistance network (9) to the voltage source (4), and on the other hand, to the evaluation stage (5). The second electrode of the storage capacitor (3) is connected to a reference potential (10). In a first aspect of the invention, the circuit can compensate for disruptive influences especially well by the evaluation stage (5) being suitable for current evaluation with essentially no voltage excursions occurring on the changeover contact (2). According to a second aspect of the invention, the evaluation stage (105) is suitable for voltage evaluation and the resistor network (108) is adjustable.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.