基于忆阻的全功能巴甫洛夫联想记忆电路的设计、实现与分析

Memory Circuit Design,Implementation and Analysis Based on Memristor Full-function Pavlov Associative

联想记忆是一种描述生物学习和遗忘过程的重要机制,对构建神经形态计算系统和模拟类脑功能有重要的意义,设计并实现联想记忆电路成为人工神经网络领域内的研究热点。巴甫洛夫条件反射实验作为联想记忆的经典案例之一,其硬件电路的实现方案仍然存在电路设计复杂、功能不完善以及过程描述不清晰等问题。基于此,该文融合经典的条件反射理论和纳米科学技术,提出一种基于忆阻的全功能巴甫洛夫联想记忆电路。首先,基于水热合成法和磁控溅射法制备了Ag/TiO_(x)nanobelt/Ti结构的忆阻器,通过电化学工作站、四探针测试台和透射电子显微镜联合完成相应的性能测试;接着,利用测试得到的电化学数据,构建了Ag/TiO_(x)nanobelt/Ti忆阻器的数学模型和SPICE电路模型,并通过客观评价验证模型的精确度;进一步,基于提出的Ag/TiO_(x)nanobelt/Ti忆阻器模型,设计了一种全功能巴甫洛夫联想记忆电路,通过电路描述和功能分析,论述了该电路能够正确模拟巴甫洛夫实验中2类学习过程和3类遗忘过程;最后,通过一系列计算机仿真和分析,验证了所提方案的正确性和有效性。

Associative memory is an important mechanism describing biological learning process and forgetting process,which is of great significance for constructing neuromorphic computing systems,as well as simulating brain-like functions.As a result,the design and implementation of associative memory circuit has become a research hotspot in the field of artificial neural networks.Pavlov conditioning experiment,as one of the classic cases of associative memory,its hardware implementation still suffers from some limitations such as complex circuit configuration,imperfect function and unclear process description.Based on this,a memory circuit is proposed based on memristor full-fuction pavlov associative in this paper,which combines the classical conditioned reflection theory and nano science and technology.Firstly,the Ag/TiOx nanobelt/Ti memristor is prepared using hydrothermal synthesis method and magnetron sputtering method,and its performance testing is conducted jointly by electrochemical workstation,four-probe test bench,and transmission electron microscope.Then,the mathematical model and SPICE circuit model of the Ag/TiO_(x)nanobelt/Ti memristor are built up respectively,based on the electrochemical data derived from the performance testing,and the model accuracy is verified by objective evaluation.Furthermore,the proposed Ag/TiO_(x)nanobelt/Ti memristor model is applied to the implementation of a full-function Pavlovian associative memory circuit.The specific circuit description and function analysis illustrate that this circuit is able to simulate two kinds of learning process and three kinds of forgetting process in Pavlov experiment.Finally,a series of computer simulation and analysis are carried out,which verifies the validity and effectiveness of the entire scheme.