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arXiv · 2502.19399

DROID: Discrete-Time Simulation for Ring-Oscillator-Based Ising Design

Abhimanyu Kumar·Ramprasath S.·Chris H. Kim·Ulya R. Karpuzcu·Sachin S. Sapatnekar
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Abstract

Many combinatorial problems can be mapped to Ising machines, i.e., networks of coupled oscillators that settle to a minimum-energy ground state, from which the problem solution is inferred. This work proposes DROID, a novel event-driven method for simulating the evolution of a CMOS Ising machine to its ground state. The approach is accurate under general delay-phase relations that include the effects of the transistor nonlinearities and is computationally efficient. On a realistic-size all-to-all coupled ring oscillator array, DROID is nearly four orders of magnitude faster than a traditional HSPICE simulation in predicting the evolution of a coupled oscillator system and is demonstrated to attain a similar distribution of solutions as the hardware.

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Abhimanyu Kumar, Ramprasath S., Chris H. Kim, Ulya R. Karpuzcu, Sachin S. Sapatnekar. 2025-02-26. DROID: Discrete-Time Simulation for Ring-Oscillator-Based Ising Design. https://arxiv.org/abs/2502.19399

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