Neuromorphic system with phase-change synapses for pattern learning and feature extraction

Abstract

Neuromorphic systems provide biologically inspired methods of computing, alternative to the classical von Neumann approach. In these systems, computation is performed by a network of spiking neurons controlled by the values of their synaptic weights, which are updated in the process of learning. Providing efficient synaptic learning rules, such as spike-timing-dependent plasticity (STDP), is a challenging task. These rules need to primarily use local information, but simultaneously develop a knowledge representation that is useful in the global context. From the implementation viewpoint, they also need to be suited for particular hardware technology. In this work, we propose a system with spiking neurons and synapses realized using phase-change devices. We design in a bottom-up manner an architecture for pattern learning and feature extraction. Experimental results from a prototype hardware platform demonstrate the capabilities of the proposed neuromorphic system.