Browse Prior Art Database

Capacitor Read Only Store

IP.com Disclosure Number: IPCOM000094730D
Original Publication Date: 1965-May-01
Included in the Prior Art Database: 2005-Mar-06
Document File: 2 page(s) / 42K

Publishing Venue

IBM

Related People

Draper, SW: AUTHOR [+3]

Abstract

Drawing 1 shows schematically a portion of a capacitor read-only store. A drive line is capacitively coupled to a sense line for a binary 1. The drive line is capacitively coupled to ground for a binary 0.

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Capacitor Read Only Store

Drawing 1 shows schematically a portion of a capacitor read-only store. A drive line is capacitively coupled to a sense line for a binary 1. The drive line is capacitively coupled to ground for a binary 0.

Drawing 2 shows, in section, one construction of this store using a printed circuit board with pluggable capacitor elements. The printed circuit board consists of insulating layer 1. This has parallel sense lines 2 deposited on it, insulating layer 3 having parallel drive lines 4, only one shown, deposited at right angles to lines 2, and conductive ground plane 5. Holes are provided through the board at the crossover points of lines 2 and 4 and these extend into the holes. Coupling element 6 is used for a binary 0 and provides capacitive coupling from drive to ground. Capacitive coupling from drive to sense is reduced by making element 6 thin in the region of layer 1 and coating it with insulating material 7. Coupling element 8 is used for a binary 1 and provides capacitive coupling from drive to sense. This element can be identical to an inverted element 6.

The elements are thinly coated with a dielectric material to increase coupling and to eliminate short circuiting. A constant sense impedance is obtained by interchanging layers 1 and 3 in Drawing 2. Drawing 3 shows schematically a similar arrangement which, by suitable adjustment of the values of the coupling capacitors, gives constant impedance for both drive and sense lines. The ...