APPLICATIONS OF TECHNOLOGY:

Rapid Single-Flux Quantum (RSFQ) circuits for superconducting digital computing in applications such as:

  • High-speed and low power digital circuits
  • Quantum computing
  • Cryo-sensors
  • HPC accelerators
  • Datacenters 

BENEFITS:

  • Methodology can design a toggle flip-flop with any number of outputs
  • Reduction in area, power, and latency of certain RSFQ compute and memory circuits

BACKGROUND:

Superconducting digital computing predominantly uses single-flux quanta, typically based on the Rapid Single-Flux Quantum (RSFQ) logic family, to encode information and has demonstrated significant improvements in performance compared to Complementary Metal-Oxide-Semiconductor (CMOS). An important building block of popular RSFQ circuits such as registers, counters, frequency dividers, and counting networks, is a toggle flip-flop (TFF). Traditional TFFs have a single input that accepts pulses and distributes them in a round robin manner among its one or two outputs. Because TFFs have only two outputs, larger-scale circuits need multiple TFFs as well as other cells, which drastically increases area.

TECHNOLOGY OVERVIEW: 

Scientists at Berkeley Lab have developed a multi-output TFF design which reduces the area, power, and latency of multiple types of compute and memory circuits with multiple outputs. This TFF is a new cell that replaces circuits with tens of cells, leading to a TFF that can have more than two outputs, which can be determined at design time. In TFFs, information is internally temporarily stored in a SQUID loop in the form of magnetic flux quanta. The design methodology of the TFFs includes a process on duplicating the number of SQUIDs and outputs, as well as how to tune every Josephson Junction (the fundamental building block in the circuit) for correct operation. 

DEVELOPMENT STAGE: 

Characteristic proof of concept.

PRINCIPAL INVESTIGATORS:

Meriam Gay Bautista

George Michelogiannakis

Darren Lyles

Patricia Gonzalez-Guerrero

IP Status: 

Patent pending.

OPPORTUNITIES: 

Available for licensing or collaborative research