Browse Prior Art Database

Logic Gate Personalization

IP.com Disclosure Number: IPCOM000085155D
Original Publication Date: 1976-Feb-01
Included in the Prior Art Database: 2005-Mar-02
Document File: 2 page(s) / 84K

Publishing Venue

IBM

Related People

Herrell, DJ: AUTHOR

Abstract

On a logic chip carrying a regular rectangular array of potential logic gate sites, it is advantageous and greatly simplifying if the logic gate site can be personalized with only a single metallization level. For example, a group of individual Josephson junctions (or interferometers) can be arranged as either an AND gate or an OR gate just by a suitable choice of the original layout, together with a change in the last mask level.

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 100% of the total text.

Page 1 of 2

Logic Gate Personalization

On a logic chip carrying a regular rectangular array of potential logic gate sites, it is advantageous and greatly simplifying if the logic gate site can be personalized with only a single metallization level. For example, a group of individual Josephson junctions (or interferometers) can be arranged as either an AND gate or an OR gate just by a suitable choice of the original layout, together with a change in the last mask level.

An example is shown in Fig. 1 for AND and OR gates based on three Josephson junctions, the circuit diagrams of which are shown in Figs. 2 and 3, respectively. In this particular example, the large rectangular Josephson junction region with two turns can be considered as either an in-line gate or an N-junction interferometer structure. The same idea can be extended to include inverter circuits similar to that shown in Fig. 4. ADVANTAGES. 1) All logic gate sites are identical up to the last level. 2) Simplifies logic gate definition. 3) Simplifies checking: once the basic gate structure has been defined, the designer/checker needs only to note the final personalization used.

1

Page 2 of 2

2

[This page contains 5 pictures or other non-text objects]