Circuit for fingerprint sensing and electronic device comprising the circuit
US10423286B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 9, 2018 |
| Grant date | Sep 24, 2019 |
| Priority date | — |
| Expiry date | Mar 25, 2038 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G2358/00
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A circuit for fingerprint detection is disclosed. The circuit includes a transistor and a capacitor. The transistor includes a gate configured to, in response to a touch event of an object, sense a capacitance associated with the object. The capacitor, coupled between a first node and a second node, is configured to establish a voltage across the first node and the second node in response to a first control signal, and establish a compensation voltage at the first node in response to a second control signal. The transistor is configured to flow a current therethrough in response to a third control signal. The current has a magnitude independent of the threshold voltage of the transistor due to the compensation voltage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.