Browse Prior Art Database

Read Only Memory

IP.com Disclosure Number: IPCOM000097152D
Original Publication Date: 1962-Jun-01
Included in the Prior Art Database: 2005-Mar-07
Document File: 2 page(s) / 38K

Publishing Venue

IBM

Related People

Young, JER: AUTHOR

Abstract

This read only memory comprises a matrix of row and column conductors, selected cross over points of which are interconnected by resistors. The presence of a resistor at a cross over point represents a 1 and the absence of a resistor a 0. A point is identified by a column conductor and a row conductor. The memory is interrogated by testing for continuity between a column and row conductor.

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Read Only Memory

This read only memory comprises a matrix of row and column conductors, selected cross over points of which are interconnected by resistors. The presence of a resistor at a cross over point represents a 1 and the absence of a resistor a 0.

A point is identified by a column conductor and a row conductor.

The memory is interrogated by testing for continuity between a column and row conductor.

When the memory is constructed initially, the conductors are interconnected at every cross-over point by a resistive fuse element. The fuse elements all have similar characteristics. By selectively blowing fuses a pattern is established in the memory. A selected fuse element is blown by applying a voltage between the selecting conductors while holding the other conductors substantially at ground. Vapor deposition is used for forming the fuse elements.

The memory array is formed by spirally winding a fine fuse wire on to a printed circuit card. The wire is then dip soldered to the Y conductors. The short wire loops joining the Y conductors are cut away. An insulated stack of cards is then formed and the X conductors soldered in position. The X conductors are then linked to the Y conductors through fuse elements. Load resistors R are connected in series with the Y conductors. Selected fuse elements are blown to form the read only memory.

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