Capacitive fingerprint sensor with quadrature demodulator and multiphase scanning
US9542588B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 27, 2015 |
| Grant date | Jan 10, 2017 |
| Priority date | — |
| Expiry date | Mar 27, 2035 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06V40/1376
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A fingerprint sensing circuit, system, and method is disclosed. The fingerprint sensor maybe include a plurality of inputs coupled to a plurality of fingerprint sensing electrodes and to an analog front end. The analog front end may be configured to generate at least one digital value in response to a capacitance of at least one of the plurality of fingerprint sensing electrodes. Additionally, the analog front end may include a quadrature demodulation circuit to generate at least one demodulated value for processing by a channel engine. The channel engine may generate a capacitance result value that is based, in part, on the demodulated value and is stored in a memory.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.