Browse Prior Art Database

Analog Memory Element

IP.com Disclosure Number: IPCOM000120163D
Original Publication Date: 1991-Mar-01
Included in the Prior Art Database: 2005-Apr-02
Document File: 1 page(s) / 50K

Publishing Venue

IBM

Related People

Camp, WO: AUTHOR

Abstract

Disclosed is a device for storing an analog value using a superconducting loop. This analog value thus stored is further used as an input to a multiplier circuit, by reading the magnetic field with a Hall effect device.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 78% of the total text.

Analog Memory Element

      Disclosed is a device for storing an analog value using a
superconducting loop.  This analog value thus stored is further used
as an input to a multiplier circuit, by reading the magnetic field
with a Hall effect device.

      It is useful to have a nonvolatile device to store an analog
value.  A means of doing this is with a loop of superconducting
material.  In the configuration shown in the figure, the analog value
is stored in the magnetic field 4 of the superconducting loop (1 and
2) and the analog value is sensed with a nearby Hall Effect device 5.
In this particular configuration, the hall current 6 multiplies an
input current 7 in an FET 9 to give a resulting output current 8 that
is the product of the input and stored analog values.  All of these
components are realizable in miniature thin film form suitable for
high density integrated circuits.

      It is a feature of the analog memory element, that the analog
value can be stored perpetually as long as the temperature is
maintained at a sufficiently low value, below that of the lowest
superconductor Tc 2.  Additionally, the stored analog value will be
changed by raising the temperature above the lowest superconductor Tc
2, so that the current in the loop can now be modified by a control
current 3.  Reducing the temperature again will store the new analog
value.  The two different Tc's can be obtained by using different
superconducting alloys.  In order to stabiliz...