ELECTRONIC LEARNING SYNAPSE WITH SPIKE-TIMING DEPENDENT PLASTICITY USING UNIPOLAR MEMORY-SWITCHING ELEMENTS

According to embodiments of the invention, a system, method and computer program product producing spike-dependent plasticity in an artificial synapse. In an embodiment, a method includes: receiving a pre-synaptic spike in an electronic component; receiving a post-synaptic spike in the electronic component; in response to the pre-synaptic spike, generating a pre-synaptic pulse that occurs a predetermined period of time after the received pre-synaptic spike; in response to the post-synaptic spike, generating a post-synaptic pulse that starts at a baseline value and reaches a first voltage value a first period of time after the post-synaptic spike, followed by a second voltage value a second period of time after the post synaptic spike, followed by a return to the baseline voltage a third period of time after the post-synaptic spike; applying the generated pre-synaptic pulse to a pre-synaptic node of a synaptic device that includes a uni-polar, two-terminal bi-stable device in series with a rectifying element; and applying the generated post-synaptic pulse to a post-synaptic node of the synaptic device, wherein the synaptic device changes from a first conductive state to a second conductive state based on the value of input voltage applied to its pre and post-synaptic nodes, wherein the resultant state of the conductance of the synaptic device after the pre- and post-synaptic pulses are applied thereto depends on the relative timing of the received pre-synaptic spike with respect to the post synaptic spike.