Analog waveform transducing circuit

A superconductive sample and hold circuit for maintaining a particular current level regardless of variations in the input to said circuit comprising,

• a first superconductive circuit connected between input and output terminals,
• a Josephson device connected in said first superconductive circuit,
• an analog current signal source,
• means for applying said analog signal to said input terminal,
• a second superconductive circuit connected between said input and output terminals and adapted to be coupled to utilization means, said second superconductive circuit having an inductance greater than the inductance of said Josephson device,
• and control means magnetically coupled to said Josephson device for forcing said analog signal to flow through said second superconductive circuit and for,
• at times, switching said Josephson device to a superconductive state to thereby allow at least some of said analog signal to flow in said Josephson device,
• whereby current in said second superconductive circuit will track said analog signal when said Josephson device is resistive and said current in said second superconductive circuit will be maintained, when said Josephson device is superconductive, at a value which was flowing in said second superconductive circuit when said Josephson device becomes superconductive.

An analog waveform transducing circuit responsive to an analog signal input in the form of a current for transferring at least a predetermined portion of said input current comprising:

• a Josephson tunnelling device disposed in a superconducting path,
• means disposed in parallel with said device for trapping at least a single flux quantum,
• an analog current signal source,
• means for applying said analog signal to said Josephson tunnelling device, and
• means coupled to said device for switching said device to transfer the value of said analog signal, at the time of switching, to said trapping means and to reset said device such that at least a single flux quantum is trapped in said trapping means.

An analog waveform transducing circuit including at least a pair of circuits responsive to an analog signal input in the form of a current for transferring at least a predetermined portion of said input current to said second circuit comprising:

• a first superconducting including a Josephson device connected between an input and output terminal,
• a second superconducting circuit connected in parallel with said first circuit and having an inductance greater than that of said first circuit,
• an analog current signal source,
• means for applying said analog signal to said input terminal, and
• means coupled to said device for switching said device to transfer at least a portion of said analog signal between said circuits.

An analog waveform transducing circuit including at least a pair of circuits responsive to an analog signal input in the form of a current for transferring at least a predetermined portion of said input current between said circuits comprising:

• a first superconducting circuit including a Josephson device connected to input and output terminals,
• a second superconducting circuit connected in parallel with said first circuit and having an inductance greater than that of said first circuit,
• an analog current signal source,
• means for applying said analog signal to said input terminal, and
• means coupled to said device for switching said device to change the quantity of flux in said second circuit by at least a single flux quantum.

An analog waveform transducing circuit responsive to an analog signal input in the form of a current for transferring at least a predetermined portion of said input current comprising:

• a Josephson tunnelling device disposed in a superconducting path,
• means disposed in parallel with said device for trapping at least a single flux quantum,
• an analog current signal source,
• means for applying said analog signal to said Josephson tunnelling device, and
• means coupled to said device for switching said device to change the flux of said trapping means by at least a single flux quantum.