The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 10, 2018
Filed:
Sep. 09, 2014
Apple Inc., Cupertino, CA (US);
Giovanni Gozzini, Cupertino, CA (US);
Gordon S. Franza, Cupertino, CA (US);
Jean-Marie Bussat, Cupertino, CA (US);
Patrick J. Landy, Cupertino, CA (US);
Apple Inc., Cupertino, CA (US);
Abstract
A capacitive fingerprint sensor includes an array of capacitive sensing elements, readout circuitry electrically coupled to the array of capacitive sensing elements, a block first digital to analog converter (DAC), at least one second DAC, and at least one summing junction electrically coupled to the readout circuitry, the first DAC, and the at least one second DAC. The readout circuitry is adapted to read out pixel voltages from a group of each block of capacitive sensing elements. The first DAC is adapted to provide a block baseline voltage for each block of capacitive sensing elements. The second DAC is adapted to provide a pixel baseline voltage difference for one capacitive sensing element of each group of each block. The summing junction is adapted to subtract the received block baseline voltage and the received pixel baseline voltage difference from the corresponding pixel voltage of each row of each block.