Silead Inc.

Xianggui Zhao

Taiyi Cheng

A fingerprint information detection circuit comprises an amplification unit, a source follower unit, a reset unit, and a feedback unit. The amplification unit is coupled to the source follower unit. The reset unit is coupled to both the feedback unit and the amplification unit. The feedback unit and the amplification unit are coupled. The reset unit includes a first transistor and a reset transistor, wherein source and drain electrodes of the first transistor are coupled, wherein one of source and drain electrodes of the reset transistor is coupled to the source and drain electrodes of the first transistor.

Fingerprint information detection circuit

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.

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Shanghai, China

Xianggui Zhao