Bridging Quantized Artificial Neural Networks and Neuromorphic Hardware

Abstract

Neuromorphic hardware aims to leverage distributed computing and event-driven circuit design to achieve an energy-efficient AI system. The name "neuromorphic" is derived from its spiking and local computing nature, which mimics the fundamental activity of an animal's nervous system. In neuromorphic hardware, neurons, i.e., computing cores use single-bit, event-driven data (called spikes) for inter-communication, which differs substantially from conventional hardware. To leverage the advantages of neuromorphic hardware and implement a computing model, the conventional approach is to build spiking neural networks (SNNs). SNNs replace the nonlinearity part of artificial neural networks (ANNs) in the realm of deep learning with spiking neurons, where the spiking neuron mimics the basic behavior of bio-neurons. However, there is still a performance gap between SNNs and their ANN counterparts. In this paper, we explore a new way to map computing models onto neuromorphic hardware. We propose a Spiking-Driven ANN (SDANN) framework that directly implements quantized ANN on hardware, eliminating the need for tuning the trainable parameters or any performance degradation. With the power of quantized ANN, our SDANN ensures a lower bound of implementation performance on neuromorphic hardware. To address the limitation of bit width support on hardware, we propose bias calibration and scaled integration methods. Experiments on various tasks demonstrate that our SDANN achieves exactly the same accuracy as the quantized ANN. Beyond toy examples and software implementation, we successfully deployed and validated our spiking models on real neuromorphic hardware, demonstrating the feasibility of the SDANN framework.