HDL-Based Modeling Approach for Digital Simulation of Adiabatic Quantum Flux Parametron Logic

Adiabatic quantum-flux-parametron (AQFP) circuits are currently verified by analog-based simulation, which would be an obstacle for large-scale circuits design. In this paper, we present a logic simulation model for AQFP logic. We made a functional model based on a finite-state machine approach using a hardware description language, which enables the simulation of large-scale AQFP circuits using commercially available logic simulation tools. We have developed a library for logic simulation and implemented an 8-bit carry look-ahead adder, which is composed of over 1000 Josephson junctions. We also include timing information in our logic simulation models for timing analysis. Since the library is based on a parameterized approach, it can be easily modified for different fabrication technologies and low-level circuit parameters.