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:
Feb. 24, 2015
Filed:
Apr. 13, 2012
Kai-chun Lin, Hsinchu, TW;
Hung-chang Yu, Hsin-Chu, TW;
Yue-der Chih, Hsin-Chu, TW;
Chun-jung Lin, Hsin-Chu, TW;
Kai-Chun Lin, Hsinchu, TW;
Hung-Chang Yu, Hsin-Chu, TW;
Yue-Der Chih, Hsin-Chu, TW;
Chun-Jung Lin, Hsin-Chu, TW;
Taiwan Semiconductor Manufacturing Co., Ltd., Hsin-Chu, TW;
Abstract
A magnetoresistive memory has first and second magnetic tunnel junction (MTJ) elements operated differentially, each with a pinned magnetic layer and a free magnetic layer that can have field alignments that are parallel or anti-parallel, producing differential high and low resistance states representing a bit cell value. Writing a high resistance state to an element requires an opposite write current polarity through the pinned and free layers, and differential operation requires that the two MTJ elements be written to different resistance states. One aspect is to arrange or connect the layers in normal and reverse order relative to a current bias source, thereby achieving opposite write current polarities relative to the layers using the same current polarity relative to the current bias source. The differentially operated MTJ elements can supplement or replace single MTJ elements in a nonvolatile memory bit cell array.