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:
Jun. 17, 2003
Filed:
Oct. 01, 2001
Takaaki Fuchikami, Ukyo-ku, JP;
Takanori Ozawa, Ukyo-ku, JP;
Rohm Co., Ltd., Kyoto, JP;
Abstract
A data memory device is provided that is capable of reading data accurately even if the reading action is repeated. Respective output ends of memory cells D -D and input ends on one side of respective exclusive OR elements Eo -Eo are interconnected, and the output end of a polarity holding cell Dc and the input ends on the other side of the respective exclusive OR elements Eo -Eo are interconnected. When it is assumed that the stored value of the memory cell D is a logic “1” and the stored value of the polarity holding cell Dc is a logic “0,” the value of the output data Do read out becomes a logic “1”. By the reversal writing action that follows, the value of the memory cell D becomes a logic “0” and the stored value of the polarity holding cell Dc becomes a logic “1.” When the value of the memory cell D is read again in that state, the value of the output data Do is still a logic “1.” That is to say, even if data reading action is repeated, values of the output data Do -Do remain unchanged. However, the direction of polarization of respective ferroelectric capacitors constituting the memory cells D -D and the polarity holding cell Dc are reversed every time of the reading.