Capacitive fingerprint sensor
US10354115B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 7, 2016 |
| Grant date | Jul 16, 2019 |
| Priority date | — |
| Expiry date | Aug 16, 2036 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06V40/1359
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
The present invention relates to a capacitive fingerprint sensor, and the capacitive fingerprint sensor includes: a fingerprint sensor electrode for sensing a fingerprint of a human body; a first transistor of which a current or an output voltage is changed according to a voltage change of capacitive coupling formed by fingerprint capacitance formed when a fingerprint contacts the fingerprint sensor electrode and coupling capacitance formed for capacitive coupling; a fifth transistor that resets a gate electrode of the first transistor and applies capacitive coupling to the gate electrode of the first transistor through a coupling pulse; a second transistor of which a current or an output voltage is changed due to a difference in the current flowing through the first transistor and a gate voltage is maintained by a capacitor; a third transistor that resets a gate electrode of the second transistor; and a fourth transistor that controls a current flowing through the second transistor or an output voltage of the second transistor and transmits the controlled current or output voltage to a readout circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.