An Improved Silicon Neuron

We describe an improved spiking silicon neuron (SN) [6] that approximates the dynamics of ionic currents of a real nerve cell. The improved version has less circuitry and fewer parameters than previous circuits thereby improving the spiking characteristics. We describe the differential equations governing the revised circuits and use them to explain the spiking properties of the SN. We also describe how to tune the parameters ef®ciently to bring the neuron quickly into its correct operating regime. The new neurons are suf®ciently robust for operation in large networks. We demonstrate their robustness by comparing the neuron's frequency-current curve between different chips for the same set of parameter values.