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. 27, 2013
Filed:
Sep. 17, 2010
Fukuo Owada, Kanagawa, JP;
Fukuo Owada, Kanagawa, JP;
Renesas Electronics Corporation, Kanagawa, JP;
Abstract
A contactless IC card which ensures the reliability of an IC chip mounted therein. Even if the distance between the contactless IC card and a reader/writer is too short, the card prevents an excessive voltage from being applied to the IC chip so that breakdown or reliability deterioration of the circuitry of the IC chip does not occur. The body of the contactless IC card has two interconnection substrates stacked between two external sheets. A first antenna coil formed on one interconnection substrate and a second antenna coil formed on the other interconnection substrate are opposite in winding direction. The number of turns of the second antenna coil is larger than that of the first antenna coil. Therefore, when the IC card comes close to the reader/writer, the voltage between two terminals of the IC chip is always smaller than the voltage induced in the second antenna coil.