The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 25, 2018
Filed:
Mar. 09, 2015
Shenzhen Goodix Technology Co., Ltd., Guangdong, CN;
Chang Zhan, Guangdong, CN;
SHENZHEN GOODIX TECHNOLOGY CO., LTD., Shenzhen, Guangdong, CN;
Abstract
A fingerprint detection circuit includes: a detection electrode, where a first capacitance is formed between a finger and the detection electrode, a second capacitance is formed between the finger and a virtual ground, and a parasitic capacitance is formed between the detection electrode and the virtual ground; an amplifier, where an inverting input end of the amplifier is connected to the detection electrode and a non-inverting input end of the amplifier is connected to an excitation signal; and a feedback capacitance, where one end of the feedback capacitance is connected to the inverting input end of the amplifier, the other end of the feedback capacitance is connected to an output end of the amplifier, and the output end of the amplifier outputs an output signal of the fingerprint detection circuit. There is no need to connect an excitation signal to a finger of a user through an external electrode.