Mutual capacitance sensing using a self-capacitance sensing device
US8779783B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 13, 2013 |
| Grant date | Jul 15, 2014 |
| Priority date | — |
| Expiry date | Jun 13, 2033 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01D5/24
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Apparatuses and methods of mutual-capacitance sensing with a capacitance-sensing circuit, such as a self-capacitance sensing device (CSD). One apparatus includes an input node coupled to a capacitance sense pin to couple to a first electrode of a sense array, a transmit (TX) signal generation circuit to generate a TX signal to drive a second electrode of the sense array, logic circuitry coupled to the TX signal generation circuit and the input node. The logic circuitry is configured to selectively couple a first capacitor to the input node and a second capacitor to the input node timed with the TX signal. The apparatus further includes an analog-to-digital converter (ADC) coupled to receive a receive (RX) signal from the input node and to convert the RX signal into a digital value, the digital value representing a mutual capacitance between the first electrode and the second electrode.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.