Patent · US Expired

Method of writing to a multi-state magnetic random access memory cell

US6956764B2 · kind B2 · utility

19Cited by
7References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 25, 2003
Grant dateOct 18, 2005
Priority date
Expiry dateDec 7, 2023

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11C11/5607
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A method to switch a scalable magnetoresistive memory cell including the steps of providing a magnetoresistive memory device (12) having two bits (18) and (20) sandwiched between a word line (14) and a digit line (16) so that current waveforms (104) and (106) can be applied to the word and digit lines at various times to cause a magnetic field flux HW and HD to rotate the effective magnetic moment vectors (86) and (94) of the device (12) by approximately 180°. Each bit includes N ferromagnetic layers (32) and (34, 42) and (44, 60) and (62, 72 and 74) that are anti-ferromagnetically coupled. N can be adjusted to change the magnetic switching volume of the bit. One or both bits may be programmed by adjusting the current in the word and/or digit lines.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.