The invention discloses a synaptic plastic mechanism bionic circuit based on a threshold symmetric
memristor, and relates to the technical field of bionic circuits, the bionic circuit comprises a pre-synaptic
neuron circuit, the threshold symmetric
memristor and a post-synaptic
neuron circuit; the bionic circuit is divided into an excitatory synaptic moldability mechanism circuit and an inhibitory synaptic moldability mechanism circuit according to a synaptic moldability mechanism; the design method of the circuit comprises the following steps: firstly, designing
neuron waveforms before and after
synapse, then traversing changes of memristive
synapse conductance values at different time intervals to obtain a corresponding curve of the conductance changes and the time intervals, verifying the fitting degree of a biological
synapse plastic mechanism curve and the curve, and if the fitting degree is low, determining that the biological synapse plastic mechanism curve is not matched with the curve. And if not, redesigning the pulse waveforms before and after synapse. The
synaptic plasticity mechanism simulated by the bionic circuit provided by the invention and a biological synaptic STDP mechanism model have a small fitting error, the provided design method is higher in universality, circuit parameters can be adjusted according to different memristors, and different forms of biological
synaptic plasticity mechanisms can be simulated.