CAPACITIVE FINGERPRINT SENSING UNIT CAPACITANCE MEASURING CIRCUIT OF A FINGERPRINT SENSOR AND FINGERPRINT SENSING DEVICE HAVING THE SAME

摘要

Disclosed are a capacitive fingerprint recognition unit for capacitively detecting a user's fingerprint using a TFT sensor array, a capacitance measurement circuit of a fingerprint sensor, and a fingerprint recognition device having the same. The capacitive fingerprint recognition unit includes: a TFT sensor array including a fingerprint recognition pattern connected to each of the plurality of TFTs; A gate driver sequentially providing a gate signal to the gate line; An upper switch connected to one end of each of the sensing lines to switch a driving signal for fingerprint recognition and an output path of a sensing signal according to fingerprint recognition; And a lower switch connected to the other end of each of the sensing lines to switch the driving signal for the fingerprint recognition and the output path of the sensing signal according to the fingerprint recognition. Accordingly, the user's fingerprint is sensed using a TFT sensor array in a capacitive manner, but the sensing signal path via the TFT sensor array is changed from one side of the TFT sensor array to the other side or the other side to one side to be acquired through the fingerprint sensor. The error rate of the measured value can be reduced.