Exploiting neurosynaptic device mismatch for efficient inference and reproducible learning in mixed-signal neuromorphic processors
Fredrik Sandin a, Mattias Nilsson a, Foteini Liwicki a
a EISLAB, Lulea University of Technology, Sweden
Proceedings of Materials, devices and systems for neuromorphic computing 2022 (MatNeC22)
Groningen, Netherlands, 2022 March 28th - 29th
Organizers: Jasper van der Velde, Elisabetta Chicca, Yoeri van de Burgt and Beatriz Noheda
Invited Speaker, Fredrik Sandin, presentation 004
DOI: https://doi.org/10.29363/nanoge.matnec.2022.004
Publication date: 23rd February 2022

Mixed-signal neuromorphic processors with dynamic neurosynaptic elements and sparse, event-based information coding are used for ultra-low-power inference and learning. In such processors, the dynamic properties of the neurosynaptic elements are inhomogeneous due to device mismatch, i.e., the dissimilarity between small-scale integrated circuit (IC) components. We describe how the resulting inhomogeneous neurosynaptic dynamics have been exploited for resource-efficient spatiotemporal inference with single neurons and spiking neural networks. For example, we demonstrate: (i) how inhibitory–excitatory pairs of dynamic synapses can be used to mimic non-spiking post inhibitory rebound in an auditory feature detection circuit of crickets, and (ii) how spatiotemporal receptive fields of output-neurons in the Spatiotemporal Correlator (STC) network can be implemented using balanced disynaptic inputs instead of dedicated axonal or neuronal delays. In experiments with the DYNAP-SE neuromorphic processor, we demonstrate synapse level temporal feature tuning with a configurable timescale of up to 0.1 seconds. This approach leads to about one order of magnitude reduction of the energy dissipation per lateral connection in an STC-type network with disynaptic dynamics instead of dedicated delay neurons. We discuss some desired properties of neuromorphic devices and materials in a regime where device mismatch constitutes the basis for efficient inference and reproducible learning.

This work was supported by The Kempe Foundations, project numbers JCK-1809 and SMK-1429.

© FUNDACIO DE LA COMUNITAT VALENCIANA SCITO
We use our own and third party cookies for analysing and measuring usage of our website to improve our services. If you continue browsing, we consider accepting its use. You can check our Cookies Policy in which you will also find how to configure your web browser for the use of cookies. More info