A switched-capacitor implementation of short-term synaptic dynamics

In this paper we present a novel switched-capacitor implementation of short-term synaptic dynamics with simultaneous depression and facilitation. The developed circuit model is a modified version of a model of neurotransmitter release derived from biological measurements. Despite the simplicity of the circuit the rich dynamics of the original model can be delivered. By completely relying on SC techniques for all calculations, our circuit is significantly less sensitive to process variations and easier to calibrate than commonly employed subthreshold circuits. The circuit makes use of a technique for minimizing leakage effects allowing for real-time operation with time constants up to several seconds. Functionality and robustness of the circuit are verified by simulations and comparisons to the original model.