Dismiss
InnovationQ will be updated on Sunday, Oct. 22, from 10am ET - noon. You may experience brief service interruptions during that time.
Browse Prior Art Database

Input Output Connection To A Cryogenic Computer

IP.com Disclosure Number: IPCOM000097125D
Original Publication Date: 1962-May-01
Included in the Prior Art Database: 2005-Mar-07
Document File: 2 page(s) / 33K

Publishing Venue

IBM

Related People

Sobol, H: AUTHOR [+2]

Abstract

In a cryogenic computer, one of the severe problems is heat loss by conduction through the wires which connect to the superconducting circuitry. The heat loss through these wires can be reduced by reducing the number of wires. One way of reducing the number of wires is to use the same wires for both input and output, i.e., by multiplexing. Two methods for multiplexing the input and output lines of a cryogenic computer are shown.

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 59% of the total text.

Page 1 of 2

Input Output Connection To A Cryogenic Computer

In a cryogenic computer, one of the severe problems is heat loss by conduction through the wires which connect to the superconducting circuitry. The heat loss through these wires can be reduced by reducing the number of wires. One way of reducing the number of wires is to use the same wires for both input and output, i.e., by multiplexing. Two methods for multiplexing the input and output lines of a cryogenic computer are shown.

The upper circuit includes three cryotrons 10, 11 and 12, a line 14 which goes from the cryogenic circuitry to circuitry at room temperature, two lines 13 and 15 which connect to the cryogenic circuitry and two command lines 17 and
18. Line 14 is used for both input and output and it has a constant D. C. bias current flowing in it. The circuit has two modes of operation. In the first mode, signals on line 13 are coupled from the cryogenic circuitry to output line 14 through cryotron 10. In the second mode, signals from line 14 are coupled to the cryogenic circuitry through cryotron 12 and line 15. The circuit is set in either the first or second mode of operation by signals on lines 17 and 18.

In order to place the circuit in the readout mode, a signal is applied to line 17 to bias cryotron 10 so that signals on line 13 can make the gating element of cryotron 10 resistive, thus coupling signals from line 13 to line 14. The circuit is placed in the readin mode of operation by applying current...