FINGERPRINT SENSORS AND ELECTRONIC DEVICES HAVING THE SAME

摘要

A fingerprint sensor includes a pixel array, an offset cancellation circuit, a correlated double sampling and integration circuit, a sample and hold circuit, and an analog-to-digital converter. The pixel array includes unit pixels arranged in rows and columns, each of which generates an analog signal by detecting a fingerprint of a user. The offset cancellation circuit receives the analog signal from the unit pixels through a plurality of column lines, and outputs one of the analog signal and an offset cancellation signal as an integration signal based on an offset control signal. The correlated double sampling and integration circuit accumulatively performs a correlated double sampling operation and an integration operation on the integration signal to generate an accumulation signal. The sample and hold circuit samples the accumulation signal based on a hold signal to generate a sampling signal. The analog-to-digital converter converts the sampling signal to a digital signal.

主权项

1. A fingerprint sensor, comprising:
a pixel array including a plurality of unit pixels arranged in rows and columns, each of the plurality of unit pixels configured to generate an analog signal by detecting a fingerprint of a user; an offset cancellation circuit configured to receive the analog signal from the plurality of unit pixels through a plurality of column lines, the offset cancellation circuit configured to output one of the analog signal and an offset cancellation signal as an integration signal based on an offset control signal; a correlated double sampling and integration circuit configured to accumulatively perform a correlated double sampling operation and an integration operation on the integration signal to generate an accumulation signal; a sample and hold circuit configured to sample the accumulation signal based on a hold signal to generate a sampling signal; an analog-to-digital converter configured to perform an analog-to-digital conversion operation on the sampling signal to generate a digital signal; and a controller configured to generate the offset control signal and the hold signal.