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arXiv · 2609.07907

A 28nm 27,648-Spin Multichip Digital Ising Accelerator with Pegasus Connectivity

Tong Wu·Atharva Raut·Ian Khor·Ziyad Alswaidan·Ting-Yu Lee·Hongchang Kuang·Navid Anjum Aadit·Anand Raju·Dhruv Chinmay·Siddharth Das·Ken Mai·Kerem Camsari·Tathagata Srimani
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Abstract

We report a 28 nm four-chip Ising accelerator with 27,648 spins, degree-15 Pegasus connectivity, and 10b coefficients. Boundary-state streaming overlaps interchip transfers with spin updates, achieving 98.03% simulated weak-scaling efficiency. At 140 MHz, the four-chip system delivers 30.24G peak updates/s at 1.2 pJ/update including I/O power, with 11.5$\times$ the throughput and approximately one-quarter the logic-plus-SRAM area per spin of a prior 28 nm multichip design. We demonstrate MaxCut, spin glass, frustrated loops, factorization, and 3SAT.

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Tong Wu, Atharva Raut, Ian Khor, Ziyad Alswaidan, Ting-Yu Lee, Hongchang Kuang, Navid Anjum Aadit, Anand Raju, Dhruv Chinmay, Siddharth Das, Ken Mai, Kerem Camsari, Tathagata Srimani. 2026-09-07. A 28nm 27,648-Spin Multichip Digital Ising Accelerator with Pegasus Connectivity. https://arxiv.org/abs/2609.07907

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