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. 14, 2015
Filed:
May. 08, 2013
Pixart Imaging Inc., Hsin-Chu, TW;
Yung-Hung Chen, Hsin-Chu, TW;
Pixart Imaging Inc., Hsin-Chu, TW;
Abstract
A key press detecting circuit and method detect the status of multiple keys through a single pin. In an embodiment, a constant current is provided to apply to a key module through a single pin, to generate a voltage at the single pin that is related to the equivalent resistance of the key module observed from the single pin, and the voltage of the single pin is compared with a set of reference values to identify the status of the plurality of keys. In another embodiment, a variable current is provided to apply to a key module through a single pin in such a way that the variable current is adjusted to maintain a constant voltage at the single pin, and the variable current is compared with a set of reference values to identify the status of the plurality of keys.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile