Browse Prior Art Database

Associative Memory Using Exchange Coupled Films

IP.com Disclosure Number: IPCOM000092258D
Original Publication Date: 1968-Nov-01
Included in the Prior Art Database: 2005-Mar-05
Document File: 2 page(s) / 46K

Publishing Venue

IBM

Related People

Lin, YS: AUTHOR [+2]

Abstract

Storage device 1 in A consists of two pairs of exchange-coupled films. Each pair has a hard anisotropy field film 2 and a soft anisotropy field film 3 in direct contact and moderately coupled via exchange interaction. The easy axes are in parallel. The pairs of films are spaced from each other by bit line 4. Word line 5 is disposed orthogonally to bit line 4. The two storage states are identified by the orientations of the magnetizations as in B. A small DC bias field is applied in the direction of bit line 4 such that both film pairs experience a slight inclination toward the direction of the bias field. This arrangement is essential to insure the simultaneous multiple bit interrogation.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 86% of the total text.

Page 1 of 2

Associative Memory Using Exchange Coupled Films

Storage device 1 in A consists of two pairs of exchange-coupled films. Each pair has a hard anisotropy field film 2 and a soft anisotropy field film 3 in direct contact and moderately coupled via exchange interaction. The easy axes are in parallel. The pairs of films are spaced from each other by bit line 4. Word line 5 is disposed orthogonally to bit line 4. The two storage states are identified by the orientations of the magnetizations as in B. A small DC bias field is applied in the direction of bit line 4 such that both film pairs experience a slight inclination toward the direction of the bias field. This arrangement is essential to insure the simultaneous multiple bit interrogation.

To interrogate the memory by content, an interrogation current is applied to bit line 4 either into or out of the drawing depending on the search for 0 or for 1 respectively. For matched conditions, the interrogation state matches the stored state, there is no induced significance.

Normal memory readout can be performed by applying a unipolar pulse on the word line. The sense signal is positive for 1 and negative for 0, and the readout is nondestructive. Writing is achieved by applying a word pulse in coincidence with a bit pulse. However, a word pulse alone is unable to switch the cell irreversibly. Therefore, simultaneous writing into multiple bit locations on the same bit line is possible.

The advantages of the structure are tha...