| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a fingerprint detection circuit that can be powered only when a finger is placed on a fingerprint sensor. <P>SOLUTION: The fingerprint detection circuit comprises a two-dimensional array sensor and a detection circuit. The fingerprint detection circuit includes a scanning means for scanning a part of the outputs of the two-dimensional array sensor; a counting means for counting the number of pulses outputted from the scanning means; a determining means for outputting a determination signal when the count of pulses by the counting means exceeds a predetermined threshold; and a power supply control means for turning on the power supply to the detection circuit when the determination signal is outputted. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
