Patent ID: 9542587
Date: 2017-01-10
CPC Classifications: G01N,G06K,G11C,H01L,H03K

Claim:
1. A fingerprint information detection circuit, comprising: an amplification unit; a source follower unit; a reset unit; and a feedback unit, wherein: the amplification unit is coupled to the source follower unit; the amplification unit is configured to receive a signal, amplify the signal to be an amplified signal, and output the amplified signal to the source follower unit; the source follower unit is configured to receive the amplified signal, perform voltage level shifting, and output a first voltage signal; wherein the first voltage signal carries fingerprint information; the reset unit is coupled to both the feedback unit and the amplification unit; the feedback unit and the amplification unit are coupled; an input port of the reset unit is used for inputting a reset signal; when the reset signal is of a high level, a reset transistor inside the reset unit becomes open, stores electric charge, and resets the feedback unit; when the reset signal is switched from the high level to a low level, the reset transistor is turned off, and injects the stored electric charge into the feedback unit and the amplification unit; and the feedback unit is configured to receive the electric charge, and output a second voltage signal to the source follower unit when it detects the fingerprint information.