Efficient Synapse Memory Structure for Reconfigurable Digital Neuromorphic Hardware

Spiking Neural Networks (SNNs) have high potential to process information efficiently with binary spikes and time delay information. Recently, dedicated SNN hardware accelerators with on-chip synapse memory array are gaining interest in overcoming the limitations of running software-based SNN in con...

Full description

Bibliographic Details
Main Authors: Jinseok Kim, Jongeun Koo, Taesu Kim, Jae-Joon Kim
Format: Article
Language:English
Published: Frontiers Media S.A. 2018-11-01
Series:Frontiers in Neuroscience
Subjects:
Online Access:https://www.frontiersin.org/article/10.3389/fnins.2018.00829/full
Description
Summary:Spiking Neural Networks (SNNs) have high potential to process information efficiently with binary spikes and time delay information. Recently, dedicated SNN hardware accelerators with on-chip synapse memory array are gaining interest in overcoming the limitations of running software-based SNN in conventional Von Neumann machines. In this paper, we proposed an efficient synapse memory structure to reduce the amount of hardware resource usage while maintaining performance and network size. In the proposed design, synapse memory size can be reduced by applying presynaptic weight scaling. In addition, axonal/neuronal offsets are applied to implement multiple layers on a single memory array. Finally, a transposable memory addressing scheme is presented for faster operation of spike-timing-dependent plasticity (STDP) learning. We implemented a SNN ASIC chip based on the proposed scheme with 65 nm CMOS technology. Chip measurement results showed that the proposed design provided up to 200X speedup over CPU while consuming 53 mW at 100 MHz with the energy efficiency of 15.2 pJ/SOP.
ISSN:1662-453X