Browse Prior Art Database

Read Only Memory

IP.com Disclosure Number: IPCOM000097840D
Original Publication Date: 1961-Aug-01
Included in the Prior Art Database: 2005-Mar-07
Document File: 2 page(s) / 61K

Publishing Venue

IBM

Related People

Ordemann, FA: AUTHOR

Abstract

This device uses static card sensing together with a capacitor matrix arrangement to provide low cost, semi-permanent information storage.

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 87% of the total text.

Page 1 of 2

Read Only Memory

This device uses static card sensing together with a capacitor matrix arrangement to provide low cost, semi-permanent information storage.

The dielectric body 10 has a plurality of separate capacitor plates 12 printed, plated or otherwise provided on one face. Plates 12 are arranged in a matrix of rows and columns. On the opposite face of body 10 a plurality of vertical metallic strips 14 are provided. Each strip 14 is aligned with a column of plates 12. A fixed capacitance exists between each plate 12 and its opposing strip 14.

A record card 16 is supported against the body 10 so that perforations in 16 expose selected ones of plates 12 according to a predetermined information pattern. The spring pressed probes 18 contact the exposed plates 12 to complete circuits from row drivers 20 through the capacitors to column sense amplifiers 22.

Each row of index points on card 16 represents a word of stored information and each column represents a different bit position. A word is read out by energizing a selected row driver to apply voltage to those plates 12 which are contacted by the probes 18 of the energized row. Signals are transmitted through the energized capacitors to the several sense amplifiers in accordance with the punched information. While sneak circuits from energized sense lines back through capacitors of a non-selected row are possible in this device, the use of fixed value capacitance permits efficient discrimination between legitimat...