公开(公告)号：US20170091509A1

公开(公告)日：2017-03-30

申请号：US15168671

申请日：2016-05-31

Applicant: Fingerprint Cards AB

Inventor： Frank Robert Riedijk ,  Klaas-Jan de Lange

IPC: G06K9/00

CPC classification number: G06K9/0002 ,  G06K9/22

Abstract: The present invention relates to a fingerprint sensing device for sensing a fingerprint pattern of a finger, the fingerprint sensing device comprising at least a first sensing structure and a second sensing structure; and at least a first charge amplifier and a second charge amplifier. Each charge amplifier comprises: a first input; a second input; an output; and at least one amplifier stage between the first and second inputs, and the output. The output is capacitively coupled to the first input. The first input of the first charge amplifier is connected to the first sensing structure; the first input of the second charge amplifier is connected to the second sensing structure; and the output of the first charge amplifier is capacitively coupled to the first input of the second charge amplifier to suppress the common mode component.

公开(公告)号：US09684812B2

公开(公告)日：2017-06-20

申请号：US15168671

申请日：2016-05-31

Applicant: Fingerprint Cards AB

Inventor： Frank Robert Riedijk ,  Klaas-Jan de Lange

IPC: G06K9/00

CPC classification number: G06K9/0002 ,  G06K9/22

Abstract: The present invention relates to a fingerprint sensing device for sensing a fingerprint pattern of a finger, the fingerprint sensing device comprising at least a first sensing structure and a second sensing structure; and at least a first charge amplifier and a second charge amplifier. Each charge amplifier comprises: a first input; a second input; an output; and at least one amplifier stage between the first and second inputs, and the output. The output is capacitively coupled to the first input. The first input of the first charge amplifier is connected to the first sensing structure; the first input of the second charge amplifier is connected to the second sensing structure; and the output of the first charge amplifier is capacitively coupled to the first input of the second charge amplifier to suppress the common mode component.