公开(公告)号：US20170344780A1

公开(公告)日：2017-11-30

申请号：US15484554

申请日：2017-04-11

Applicant: Fingerprint Cards AB

Inventor： Frank RIEDIJK ,  Hans THÖRNBLOM ,  Daniel ANDERSSON

IPC: G06K9/00

CPC classification number: G06K9/0002 ,  G06K9/00053

Abstract: There is provided a capacitive fingerprint sensing device for sensing a fingerprint pattern of a finger, the capacitive fingerprint sensor comprising: a protective dielectric top layer to be touched by the finger; a two-dimensional array of electrically conductive sensing structures arranged underneath the top layer; readout circuitry coupled to each of the electrically conductive sensing structures to receive a sensing signal indicative of a distance between the finger and the sensing structure, the readout circuitry comprising a plurality of signal amplifiers arranged underneath the array of electrically conductive sensing structures, wherein a number of signal amplifiers is lower than a number of sensing structures; and selection circuitry coupling each of the sensing structures to at least one signal amplifier and configured to select a sensing structure to be coupled to a corresponding signal amplifier. There is also provided a method for controlling a fingerprint sensing device.