Browse Prior Art Database

Magnetic Film Memory Improved Word Drive

IP.com Disclosure Number: IPCOM000093872D
Original Publication Date: 1966-Mar-01
Included in the Prior Art Database: 2005-Mar-06
Document File: 2 page(s) / 34K

Publishing Venue

IBM

Related People

Anacker, W: AUTHOR

Abstract

Many of the word drive problems commonly encountered in magnetic film memories are eliminated by this type of construction. Reduction of word current is achieved by employing looped word lines. Each comprises a plurality of series-connected loops in nested or stacked relation on the same side of the substrate. Each bit storage cell consists of two film spots respectively disposed on the forward and return paths of the word line loops. With these multiple crossings of the film spots by the series-connected word loops, each word line is coupled several times to each of the half-bit film spots. This arrangement greatly reduces the word current required for writing and reading.

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 73% of the total text.

Page 1 of 2

Magnetic Film Memory Improved Word Drive

Many of the word drive problems commonly encountered in magnetic film memories are eliminated by this type of construction. Reduction of word current is achieved by employing looped word lines. Each comprises a plurality of series-connected loops in nested or stacked relation on the same side of the substrate. Each bit storage cell consists of two film spots respectively disposed on the forward and return paths of the word line loops. With these multiple crossings of the film spots by the series-connected word loops, each word line is coupled several times to each of the half-bit film spots. This arrangement greatly reduces the word current required for writing and reading.

Read noises which are generated on the bit sense lines through the stray capacitive couplings between these lines and the word lines are effectively cancelled by the double-ended word line drive. Voltage pulses of equal magnitude and opposite polarity are applied to the two ends of the selected word line. Thus, any read-noise voltage coupled into a bit sense line through a particular capacitive coupling is cancelled by an opposite read-noise voltage coupled into that bit-sense line. Such occurs at the same instant and almost the same position through a matching capacitive coupling on the other arm of the same word-line loop.

Another advantage of the arrangement is that the respective magnetic fields applied by the word line to the associated film cells...