OTTER - Two Transistor - One RRAM Architecture for Reliable In-Memory-Computing in 28 nm CMOS Technology

Yang Chen; Daniele Storelli; Xinyi Zhao; Ankit Bende; Paul-Philipp Manea; Oliver Artner; Arun Ashok; Kay Winterberg; Godwin Paul; Siyuan Jia; Christian Roth; Sabitha Kusuma; Michael Schiek; Vikas Rana; Dirk Wouters; Stephan Menzel; Andre Zambanini; Christian Grewing; Stefan Wiefels; Susanne Hoffmann-Eifert; John Paul Strachan; Stefan van Waasen; Regina Dittmann

arXiv · 2609.08898

OTTER - Two Transistor - One RRAM Architecture for Reliable In-Memory-Computing in 28 nm CMOS Technology

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Abstract

This work presents OTTER, a 28 nm CMOS platform co-integrated with TaOx-based valence-change mechanism (VCM) RRAM, demonstrating a two-transistor-one-memristive-device (2T1R) architecture for reliable in-memory computing. The 2T1R cell combines a low-drive-current (LD) transistor and a high-drive-current (HD) transistor in parallel, providing dedicated bias paths for SET programming and RESET operation, respectively. Through systematic experimental and simulated comparison of various transistor-pairing configurations using the physical compact model JART VCM Rth, design guidelines for transistor sizing are derived, establishing the minimum RESET transistor W/L required for complete RESET as a function of the SET current compliance. The 2T1R cell is further characterized under pulse-based programming, demonstrating multilevel analog conductance tuning with narrow, well separated conductance states across six programmable levels. An analog content-addressable memory (aCAM) design based on the same 2T1R cell is additionally analyzed at the circuit level, evaluating trade-offs between top- and bottom-connected RRAM comparator configurations. A hardware implementation of compute-in-memory (CIM) multiply-and-accumulate (MAC) operations is further demonstrated on a 15 x 15 2T1R crossbar array.

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Yang Chen, Daniele Storelli, Xinyi Zhao, Ankit Bende, Paul-Philipp Manea, Oliver Artner, Arun Ashok, Kay Winterberg, Godwin Paul, Siyuan Jia, Christian Roth, Sabitha Kusuma, Michael Schiek, Vikas Rana, Dirk Wouters, Stephan Menzel, Andre Zambanini, Christian Grewing, Stefan Wiefels, Susanne Hoffmann-Eifert, John Paul Strachan, Stefan van Waasen, Regina Dittmann. 2026-09-08. OTTER - Two Transistor - One RRAM Architecture for Reliable In-Memory-Computing in 28 nm CMOS Technology. https://arxiv.org/abs/2609.08898

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