Abstract
We have developed compact analog integrated circuits that simulate two synaptic excitatory conductances. A four-transistor circuit captures the dynamics of an excitatory postsynaptic current caused by a real AMPA conductance. A six-transistor circuit simulates the effects of a real voltage-dependent NMDA conductance. The postsynaptic current dynamics are modeled by a current mirror integrator with adjustable gain. The voltage dependence of the silicon NMDA conductance is realized by a differential pair. We show the operation of these silicon synaptic conductances and their integration with the silicon neuron (Mahowald and Douglas, 1991).
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Rasche, C., Douglas, R. Silicon Synaptic Conductances. J Comput Neurosci 7, 33–39 (1999). https://doi.org/10.1023/A:1008963426194
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DOI: https://doi.org/10.1023/A:1008963426194