Hardware Implementation of Ring Oscillator Networks Coupled by BEOL Integrated ReRAM for Associative Memory Tasks

Wooseok Choi; Thomas van Bodegraven; Jelle Verest; Olivier Maher; Donato Francesco Falcone; Antonio La Porta; Daniel Jubin; Bert Jan Offrein; Siegfried Karg; Valeria Bragaglia; Aida Todri-Sanial

arXiv · 2503.14126

Hardware Implementation of Ring Oscillator Networks Coupled by BEOL Integrated ReRAM for Associative Memory Tasks

Wooseok Choi·Thomas van Bodegraven·Jelle Verest·Olivier Maher·Donato Francesco Falcone·Antonio La Porta·Daniel Jubin·Bert Jan Offrein·Siegfried Karg·Valeria Bragaglia·Aida Todri-Sanial

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Abstract

We demonstrate the first hardware implementation of an oscillatory neural network (ONN) utilizing resistive memory (ReRAM) for coupling elements. A ReRAM crossbar array chip, integrated into the Back End of Line (BEOL) of CMOS technology, is leveraged to establish dense coupling elements between oscillator neurons, allowing phase-encoded analog information to be processed in-memory. We also realize an ONN architecture design with the coupling ReRAM array. To validate the architecture experimentally, we present a conductive metal oxide (CMO)/HfOx ReRAM array chip integrated with a 2-by-2 ring oscillator-based network. The system successfully retrieves patterns through correct binary phase locking. This proof of concept underscores the potential of ReRAM technology for large-scale, integrated ONNs.

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Wooseok Choi, Thomas van Bodegraven, Jelle Verest, Olivier Maher, Donato Francesco Falcone, Antonio La Porta, Daniel Jubin, Bert Jan Offrein, Siegfried Karg, Valeria Bragaglia, Aida Todri-Sanial. 2025-03-18. Hardware Implementation of Ring Oscillator Networks Coupled by BEOL Integrated ReRAM for Associative Memory Tasks. https://arxiv.org/abs/2503.14126

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