Nonvolatile random access memory

Details Nonvolatile random access memory Nonvolatile random access memory

1992-12-18

1994-07-12

LaRoche, Eugene R.

Static information storage and retrieval

Systems using particular element

Hall effect

365171, 257421, G11C 1118

Patent

active

053294807

ABSTRACT:
A nonvolatile magnetic random access memory can be achieved by an array of magnet-Hall effect (M-H) elements. The storage function is realized with a rectangular thin-film ferromagnetic material having an in-plane, uniaxial anisotropy and inplane bipolar remanent magnetization states. The thin-film magnetic element is magnetized by a local applied field, whose direction is used to form either a "0" or "1" state. The element remains in the "0" or "1" state until a switching field is applied to change its state. The stored information is detcted by a Hall-effect sensor which senses the fringing field from the magnetic storage element. The circuit design for addressing each cell includes transistor switches for providing a current of selected polarity to store a binary digit through a separate conductor overlying the magnetic element of the cell. To read out a stored binary digit, transistor switches are employed to provide a current through a row of Hall-effect sensors connected in series and enabling a differential voltage amplifier connected to all Hall-effect sensors of a column in series. To avoid read-out voltage errors due to shunt currents through resistive loads of the Hall-effect sensors of other cells in the same column, at least one transistor switch is provided between every pair of adjacent cells in every row which are not turned on except in the row of the selected cell.

REFERENCES:
patent: 3037199 (1962-05-01), Grant
patent: 3233228 (1966-02-01), Kaspar
patent: 3521255 (1970-07-01), Arndt
patent: 3973182 (1976-08-01), Kataoka
patent: 4021767 (1977-05-01), Nonaka et al.
patent: 4028718 (1977-06-01), Migitaka et al.
patent: 4188605 (1980-02-01), Stout
patent: 4223292 (1980-09-01), Morikawa et al.
patent: 4803658 (1989-02-01), Grimes
patent: 5089991 (1992-02-01), Matthews
S. J. Hefferman, et al., "In-situ magnetizing experiments on small regular particles fabricated by electron beam lithography," J. Magnetism and Magnetic Materials, vol. 83, p. 223 (1990).
S. McVitie, et al., "Magnetic Structure Determination in Small Regularly Shaped Particles Using Transmission Electron Microscopy," IEEE Trans. on Magnetics, vol. 24, No. 2, pp. 178-180, Mar. 1988.
M. Isai, et al., "Influence of thickness on the Galvanomagnetic properties of thin InSb films for highly sensitive magnetoresistance elements," J. Appl. Phys. 59(8), pp. 2845-2848, Apr. 15, 1986.

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