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. 23, 2013
Filed:
Jun. 02, 2010
Takayuki Kawahara, Higashiyamato, JP;
Kiyoo Itoh, Higashikurume, JP;
Riichiro Takemura, Tokyo, JP;
Kenchi Ito, Kunitachi, JP;
Takayuki Kawahara, Higashiyamato, JP;
Kiyoo Itoh, Higashikurume, JP;
Riichiro Takemura, Tokyo, JP;
Kenchi Ito, Kunitachi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
To write information on a memory cell of SPRAM formed of an MOS transistor and a tunnel magnetoresistive element, the memory cell is supplied with a current in a direction opposite to a direction of a current required for writing the information on the memory cell, and then, the memory cell is supplied with a current required for writing. In this manner, even when the same information is sequentially written on the memory cell, since the currents in the two directions are caused to flow in pairs in the tunnel magnetoresistive element of the memory cell each time information is rewritten, deterioration of a film that forms the tunnel magnetoresistive element can be suppressed. Therefore, reliability of the SPRAM can be improved.