# US 10,122,351 B1 · Superconducting bi-directional current driver > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,122,351 B1 - Document ID: US10122351B1 - Status: Granted - Kind: B1 - Application number: 15/659,005 - Filed: 2017-07-25 - Granted: 2018-11-06 - Earliest claimed: 2017-07-25 - Assignees: Northrop Grumman Systems Corporation - Applicants: Ofer Naaman; Donald L. Miller; Randall M. Burnett - Inventors: Ofer Naaman; Donald L. Miller; Randall M. Burnett - Web page: https://patentgrep.com/patent/US10122351B1 ## CPC - H03K 3/38: by the use, as active elements, of superconductive devices - G11C 7/12: Bit line control circuits, e.g. drivers, boosters, pull-up circuits, pull-down circuits, precharging circuits, equalising circuits, for bit lines - G11C 11/44: using super-conductive elements, e.g. cryotron - H03K 19/1952: {with electro-magnetic coupling of the control current} - H03K: PULSE TECHNIQUE (measuring pulse characteristics G01R; modulating sinusoidal oscillations with pulses H03C; transmission of digital information H04L; discriminator circuits detecting phase difference between two signals by counting or integrating cycles of oscillation H03D3/04; automatic control, starting, synchronisation or stabilisation of generators of electronic oscillations or pulses where the type of generator is irrelevant or unspecified H03L; coding, decoding or code conversion, in general H03M) - G11C: STATIC STORES (semiconductor memory devices H10B) ## Abstract One example includes a superconducting bidirectional current driver. The current driver includes a first direction superconducting latch that is activated in response to a first activation signal and a second direction superconducting latch that is activated in response to a second activation signal. The second direction superconducting latch is activated to provide a first current path of an input current through the first direction superconducting latch and through a bidirectional current load in a first direction. The first direction superconducting latch is activated to provide a second current path of the input current through the second direction superconducting latch and through the bidirectional current load in a second direction opposite the first direction. ## Claims ### Claim 1 A superconducting bidirectional current driver comprising: a first direction superconducting latch that is activated in response to a first activation signal; and a second direction superconducting latch that is activated in response to a second activation signal, wherein the second direction superconducting latch is activated to provide a first current path of an input current through the first direction superconducting latch and through a bidirectional current load in a first direction, wherein the first direction superconducting latch is activated to provide a second current path of the input current through the second direction superconducting latch and through the bidirectional current load in a second direction opposite the first direction. ### Claim 2 (depends on 1) The current driver of claim 1, wherein each of the first direction superconducting latch and second direction superconducting latch is configured as a quantum flux device configured to be activated in response to the respective first and second activation signals provided from an activation controller to set the respective first direction superconducting latch or second direction superconducting latch to a voltage state in response to triggering of at least one Josephson junction. ### Claim 3 (depends on 1) The current driver of claim 1, wherein the superconducting bidirectional current driver is configured as an H-bridge circuit, wherein the first direction superconducting latch comprises a given first direction superconducting latch coupled between a current source and a first end of the bidirectional current load and another first direction superconducting latch coupled between a second end of the bidirectional current load and a low-voltage rail, and wherein the second direction superconducting latch comprises a given second direction superconducting latch coupled between the current source and the second end of the bidirectional current load and another first direction superconducting latch coupled between the first end of the bidirectional current load and the low-voltage rail. ### Claim 4 (depends on 3) The current driver of claim 3, further comprising a reset latch interconnecting the bidirectional current load and a node coupling the given first direction superconducting latch and the other second direction superconducting latch, the reset latch being activated to return the superconducting bidirectional current driver from a current state in which the input current is provided through the bidirectional current load to an idle state in which no current is provided through the bidirectional current load. ### Claim 5 (depends on 3) The current driver of claim 3, further comprising a shunt current path interconnecting the current source and the low-voltage rail, wherein the shunt current path is configured to provide a current path for the input current in response to concurrent activation of at least the given first direction and second direction superconducting latches. ### Claim 6 (depends on 3) The current driver of claim 3, wherein the first end of the bidirectional current load is coupled as an activation input to the given second direction superconducting latch and wherein the second end of the bidirectional current load is coupled as an activation input to the given first direction superconducting latch, wherein the given first direction superconducting latch is activated in response to activation of the other first direction superconducting latch via a first activation signal provided from an activation controller, and wherein the given second direction superconducting latch is activated in response to activation of the other second direction superconducting latch via a second activation signal provided from the activation controller. ### Claim 7 (depends on 1) The current driver of claim 1, wherein the superconducting bidirectional current driver is configured as an A-bridge circuit, wherein the first direction superconducting latch is coupled between a first end of the bidirectional current load and a low-voltage rail, wherein the second direction superconducting latch is coupled between a second end of the bidirectional current load and the low-voltage rail, the superconducting bidirectional current driver further comprising: a first inductor interconnecting the current source and the first direction superconducting latch; and a second inductor interconnect the current source and the second direction superconducting latch. ### Claim 8 (depends on 1) The current driver of claim 1, wherein the current source is configured as a flux shuttle loop current source configured to generate the input current in a storage inductor, the storage inductor being configured to provide the input current to the bidirectional current driver. ### Claim 9 (depends on 1) A memory write driver comprising the bidirectional current driver of claim 1, wherein the bidirectional current load is configured as a bidirectional inductive current load that is inductively coupled to at least one of a row or a column of a memory array, wherein the bidirectional inductive current load is configured to provide a write current a first direction to write a first memory state based on the input current being provided through the bidirectional inductive current load in the first direction, and to provide the write current on the write line in a second direction opposite the first direction to write a second memory state based on the input current being provided through the bidirectional inductive current load in the second direction. ### Claim 10 A method for providing a superconducting current through a bidirectional current load in a first direction or a second direction, the method comprising: generating an input current via a current source; providing a first activation signal to a respective first direction superconducting latch to activate the first direction superconducting latch to provide a current path for the input current from the current source through a second direction superconducting latch and through the bidirectional current load in the second direction; and providing a second activation signal to the respective second direction superconducting latch to activate the second direction superconducting latch to provide a current path for the input current from the current source through the first direction superconducting latch and through the bidirectional current load in the first direction. ### Claim 11 (depends on 10) The method of claim 10, wherein providing the first activation signal comprises providing the first activation signal to the respective first direction superconducting latch configured as a quantum flux device to set the first direction superconducting latch in a voltage state, and wherein providing the second activation signal comprises providing the second activation signal to the respective second direction superconducting latch configured as a quantum flux device to set the second direction superconducting latch in the voltage state. ### Claim 12 (depends on 10) The method of claim 10, wherein providing the first activation signal comprises activating a given first direction superconducting latch coupled between the current source and a first end of the bidirectional current load and activating another first direction superconducting latch coupled between a second end of the bidirectional current load and a low-voltage rail, and wherein providing the second activation signal comprises activating a given second direction superconducting latch coupled between the current source and the second end of the bidirectional current load and activating another second direction superconducting latch coupled between the first end of the bidirectional current load and the low-voltage rail. ### Claim 13 (depends on 12) The method of claim 12, wherein activating the other first direction superconducting latch comprises activating the other first direction superconducting latch in response to activating the given first direction superconducting latch based on a conductive coupling of the second end of the bidirectional current load to the given first direction superconducting latch, and wherein activating the other second direction superconducting latch comprises activating the other second direction superconducting latch in response to activating the given second direction superconducting latch based on a conductive coupling of the first end of the bidirectional current load to the given first direction superconducting latch. ### Claim 14 (depends on 10) The method of claim 10, further comprising providing a third activation signal to a reset latch coupled to the bidirectional current load to activate the reset latch to cease flow of the input current through the bidirectional current load. ### Claim 15 (depends on 10) The method of claim 10, wherein providing the first activation signal comprises activating a first direction superconducting latch coupled between a first end of the bidirectional current load and a low-voltage rail to provide the current path for the input current from the current source through a first inductor interconnecting the current source and the first end of the bidirectional current load, through the bidirectional current load in the second direction, and through the second direction superconducting latch to the low-voltage rail; and wherein providing the second activation signal comprises activating a second direction superconducting latch coupled between a second end of the bidirectional current load and the low-voltage rail to provide the current path for the input current from the current source through a second inductor interconnecting the current source and the second end of the bidirectional current load, through the bidirectional current load in the first direction, and through the first direction superconducting latch to the low-voltage rail. ### Claim 16 A superconducting bidirectional memory write current driver comprising: a current source configured to generate an input current; a write line associated with at least one of a row or a column of a memory array, the write line being configured to write a first memory state of at least one memory cell of the respective at least one of the row or the column based on the input current being provided through the write line in a first direction and to write a second memory state of the at least one memory cell of the respective at least one of the row or the column based on the input current being provided through the write line in a second direction opposite the first direction; a superconducting bidirectional current driver comprising: a first direction superconducting latch that is activated in response to a first activation signal; and a second direction superconducting latch that is activated in response to a second activation signal, wherein the second direction superconducting latch is activated to provide a first current path of the input current through the first direction superconducting latch and through the write line in the first direction, wherein the first direction superconducting latch is activated to provide a second current path of the input current through the second direction superconducting latch and through the write line in the second direction. ### Claim 17 (depends on 16) The memory write current driver of claim 16, wherein the superconducting bidirectional current driver is configured as an H-bridge circuit, wherein the first direction superconducting latch comprises a given first direction superconducting latch coupled between the current source and a first end of the bidirectional current load and another first direction superconducting latch coupled between a second end of the bidirectional current load and a low-voltage rail, and wherein the second direction superconducting latch comprises a given second direction superconducting latch coupled between the current source and the second end of the bidirectional current load and another first direction superconducting latch coupled between the first end of the bidirectional current load and the low-voltage rail. ### Claim 18 (depends on 17) The memory write current driver of claim 17, further comprising a reset latch interconnecting the bidirectional inductive current load and a node coupling the given first direction superconducting latch and the other second direction superconducting latch, the reset latch being activated to return the superconducting bidirectional current driver from a current state in which the input current is provided through the bidirectional inductive current load to an idle state in which no current is provided through the bidirectional inductive current load. ### Claim 19 (depends on 17) The memory write current driver of claim 17, wherein the first end of the bidirectional current load is coupled as an activation input to the given second direction superconducting latch and wherein the second end of the bidirectional current load is coupled as an activation input to the given first direction superconducting latch, wherein the given first direction superconducting latch is activated in response to activation of the other first direction superconducting latch via a first activation signal provided from an activation controller, and wherein the given second direction superconducting latch is activated in response to activation of the other second direction superconducting latch via a second activation signal provided from the activation controller. ### Claim 20 (depends on 16) The memory write current driver of claim 16, wherein the superconducting bidirectional current driver is configured as an A-bridge circuit, wherein the first direction superconducting latch comprises a first direction superconducting latch coupled between a first end of the bidirectional current load and a low-voltage rail, wherein the second direction superconducting latch comprises a second direction superconducting latch coupled between a second end of the bidirectional current load and the low-voltage rail, the superconducting bidirectional current driver further comprising: a first inductor interconnecting the current source and the first direction superconducting latch; and a second inductor interconnecting the current source and the second direction superconducting latch.