Leakage current compensation circuit
US9163954B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 29, 2011 |
| Grant date | Oct 20, 2015 |
| Priority date | — |
| Expiry date | Mar 11, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K2217/960705
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Circuitry is described for compensating leakage currents in capacitive sensing circuits. A single active leakage compensation circuit may sense a representative leakage current and drive a plurality of output transistors, each of which provides a compensating current to a respective capacitive sensing circuit. The leakage compensation circuit may sense current flow through a device substantially equivalent to a device exhibiting leakage current in a capacitive sensing circuit, and in response, provide a signal to drive one or more output transistors to supply approximately equivalent currents to a plurality of circuit nodes. For embodiments having multiple similar capacitive sensors and capacitive sensing circuits, only one transistor need be added to each capacitive sensing circuit to compensate for leakage current.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.