Compensation circuit for a TX-RX capacitive sensor
US8093914B2 · kind B2 · utility
41Cited by
3References
20Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 11, 2008 |
| Grant date | Jan 10, 2012 |
| Priority date | — |
| Expiry date | Oct 21, 2029 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R27/2605
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A capacitive sensor may include a transmit electrode and a receive electrode capacitively coupled with the transmit electrode. A capacitance sensing circuit senses a capacitance between the transmit and receive electrodes by applying a signal to the transmit electrode and rectifying a current waveform induced at the receive electrode. A compensation circuit reduces the effect of a mutual and parasitic capacitances of the transmit and receive electrode pair by adding a compensation current to the rectified current.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.