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Nonvolatile random access memoryA 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.
Document ID
20080012417
Acquisition Source
Headquarters
Document Type
Other - Patent
Authors
Wu, Jiin-Chuan
Stadler, Henry L.
Katti, Romney R.
Date Acquired
August 24, 2013
Publication Date
July 12, 1994
Subject Category
Computer Operations And Hardware
Report/Patent Number
Patent Application Number: US-PATENT-APPL-SN-993012
Patent Number: US-PATENT-5,329,480
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
Patent
US-PATENT-5,329,480
Patent Application
US-PATENT-APPL-SN-993012
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