Scaling-up resistive synaptic arrays for neuro-inspired architecture: Challenges and prospect

The crossbar array architecture with resistive synaptic devices is attractive for on-chip implementation of weighted sum and weight update in the neuro-inspired learning algorithms. This paper discusses the design challenges on scaling up the array size due to non-ideal device properties and array parasitics. Circuit-level mitigation strategies have been proposed to minimize the learning accuracy loss in a large array. This paper also discusses the peripheral circuits design considerations for the neuro-inspired architecture. Finally, a circuit-level macro simulator is developed to explore the design trade-offs and evaluate the overhead of the proposed mitigation strategies as well as project the scaling trend of the neuro-inspired architecture.