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:
Jan. 10, 2017
Filed:
Apr. 29, 2014
Silead, Inc., Shanghai, CN;
Taiyi Cheng, Shanghai, CN;
Xianggui Zhao, Shanghai, CN;
Silead, Inc., Shanghai, CN;
Abstract
The present invention relates to a chip design and discloses a fingerprint information detection circuit. The invention includes a reset unit, a feedback unit, an amplification unit and a source follower unit; the reset unit is connected to the feedback unit and amplification unit, while the feedback unit is connected to the amplification unit, and the amplification unit is connected to the source follower unit; when the reset transistor built-into the reset unit is on, it stores an electric charge, and resets the feedback unit; when the reset transistor is off, the stored electric charge is injected into the feedback unit and amplification unit; the feedback unit receives the electric charge, and outputs the second voltage signal generated when it detects fingerprints to the source follower unit; the amplification unit amplifies the received signal and outputs it to the source follower unit; the source follower unit receives the signal, performs voltage level shifting before outputting the first voltage signal that carries the detected fingerprint information. The present invention enables the circuit to use a reduced chip area, hence, saving the cost of the chip.