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arXiv · 2501.07733

Solving Boolean satisfiability problems with resistive content addressable memories

Giacomo Pedretti·Fabian Böhm·Tinish Bhattacharya·Arne Heittman·Xiangyi Zhang·Mohammad Hizzani·George Hutchinson·Dongseok Kwon·John Moon·Elisabetta Valiante·Ignacio Rozada·Catherine E. Graves·Jim Ignowski·Masoud Mohseni·John Paul Strachan·Dmitri Strukov·Ray Beausoleil·Thomas Van Vaerenbergh
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Abstract

Solving optimization problems is a highly demanding workload requiring high-performance computing systems. Optimization solvers are usually difficult to parallelize in conventional digital architectures, particularly when stochastic decisions are involved. Recently, analog computing architectures for accelerating stochastic optimization solvers have been presented, but they were limited to academic problems in quadratic polynomial format. Here we present KLIMA, a k-Local In-Memory Accelerator with resistive Content Addressable Memories (CAMs) and Dot-Product Engines (DPEs) to accelerate the solution of high-order industry-relevant optimization problems, in particular Boolean Satisfiability. By co-designing the optimization heuristics and circuit architecture we improve the speed and energy to solution up to 182x compared to the digital state of the art.

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Giacomo Pedretti, Fabian Böhm, Tinish Bhattacharya, Arne Heittman, Xiangyi Zhang, Mohammad Hizzani, George Hutchinson, Dongseok Kwon, John Moon, Elisabetta Valiante, Ignacio Rozada, Catherine E. Graves, Jim Ignowski, Masoud Mohseni, John Paul Strachan, Dmitri Strukov, Ray Beausoleil, Thomas Van Vaerenbergh. 2025-01-13. Solving Boolean satisfiability problems with resistive content addressable memories. https://doi.org/10.1038/s44335-025-00020-w

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