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arXiv · 2609.35254

MEGATRON: a 28nm Analog PCM CiM/Digital System-on-Chip for Edge GenAI at 57.5 TOPS/W and 1.52 Mparam/mm${}^2$

Alessandro Nadalini·Angelo Garofalo·Lorenzo Greco·Andrea Belano·Alessio Antolini·Francesco Zavalloni·Andrea Lico·Riccardo Zurla·Emanuela Calvetti·Luigi Croce·Marco Pasotti·Alessandro Cabrini·Eleonora Franchi Scarselli·Davide Rossi·Francesco Conti
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Abstract

We present MEGATRON, a heterogeneous Edge GenAI System-on-Chip in 28nm FD-SOI CMOS technology combining a non-volatile analog in-memory-computing engine based on a 4Mi-cell phase-change memory (PCM) array with a digital RISC-V-based flexible neural processing unit. MEGATRON demonstrates up to 3.5 TOPS/W using the RISC-V processors and 57.5 TOPS/W with PCiM, at a storage density of 1.52 Mparam/mm${}^2$ with 4-bit effective weight precision.

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Alessandro Nadalini, Angelo Garofalo, Lorenzo Greco, Andrea Belano, Alessio Antolini, Francesco Zavalloni, Andrea Lico, Riccardo Zurla, Emanuela Calvetti, Luigi Croce, Marco Pasotti, Alessandro Cabrini, Eleonora Franchi Scarselli, Davide Rossi, Francesco Conti. 2026-09-28. MEGATRON: a 28nm Analog PCM CiM/Digital System-on-Chip for Edge GenAI at 57.5 TOPS/W and 1.52 Mparam/mm${}^2$. https://arxiv.org/abs/2609.35254

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