Circuits for bistable spike-timing-dependent plasticity neuromorphic VLSI synapses
We present analog neuromorphic circuits for implementing bistable synapses with spike-timing-dependent plasticity (STDP) properties. In these types of synapses, the short-term dynamics of the synaptic efficacies are governed by the relative timing of the preand post-synaptic spikes, while on long time scales the efficacies tend asymptotically to either a potentiated state or to a depressed one. Test results from a prototype VLSI chip, containing a learning synapse connected to a preand post-synaptic integrate and fire neuron, demonstrate the synapse’s STDP learning properties, and its long-term bistable characteristics.