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:
Aug. 03, 2021
Filed:
Sep. 06, 2018
Stmicroelectronics, Inc., Coppell, TX (US);
Pierre Rizzo, Mountain View, CA (US);
Christophe Henri Ricard, Santa Clara, CA (US);
STMicroelectronics, Inc., Coppell, TX (US);
Abstract
A method and apparatus for performing a low-power presence check are provided. In the method and apparatus, a controller detects a presence of a tag by at least causing the antenna to generate a magnetic field over a first time period for detecting the tag, measuring an antenna voltage over a second time period, causing the antenna to cease generating a magnetic field over a third time period longer than the first time period and comparing the antenna voltage to an antenna reference voltage to determine whether the tag is present. The controller detects the presence of the tag in response to receiving a command from a host device for performing the low-power presence check. The command may be a one-time command for every presence check stage or a command that is repeatedly received each time the controller detects the presence of the tag.