Patent · US Expired

Ferromagnetic memory using soft magnetic material and hard magnetic material

US5864498A · kind A · utility

13Cited by
2References
15Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 1, 1997
Grant dateJan 26, 1999
Priority date
Expiry dateOct 1, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11C11/15
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A magnetic memory cell for storing binary encoded data and a memory constructed from these memory cells. A memory cell according to the present invention stores information in the direction of magnetization of a layer of magnetic material. The memory cell is constructed from a structure having a top electrode, a soft layer which includes a planar sheet of a soft magnetic material, a hard layer which includes a planar sheet of a hard magnetic material, and a bottom electrode, the soft and hard layers being sandwiched between the top and bottom electrodes. The hard and soft materials are chosen such that the magnitude to the magnetic field needed to magnetize the hard magnetic material is greater than the magnitude of the magnetic field needed to magnetize the soft magnetic material. The memory cell also includes a write circuit that generates first and second magnetic fields. The first and second magnetic fields are parallel to the planar sheet of the soft layer. The magnitudes of the first and second magnetic fields are less than that needed to magnetize the soft magnetic material. However, the magnitude of the vector sum of the first and second magnetic fields is greater than the …

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