Development of a new FitzHugh–Nagumo type simplified electronic neuron

This study aims to develop a new electronic realization of FitzHugh–Nagumo neuron. We based our work on a previously constructed circuit and modified it to reduce the number of elements. All modeling was done using ngSPICE circuit simulator. For the new developed circuit current-voltage characteristics were constructed, then dependence of signal amplitude on resistance of potentiometer was measured. By this way, we found that oscillations were bom as a result of Andronov–Hopf bifurcation like in the FitzHugh–Nagumo neuron. The different approximations of nonlinear function were considered and the dependence of the output signal on the number n of diodes in the circuit was studied. It was found that signal becomes more pulse-like with increase of n: the fewer diodes used, the smoother the peak was, up to the plateau-like segment for n = 1. At the same time, the dependence of the oscillation frequency on n is weak: in general, the period decreases slightly with increasing n. As a result, we developed a new simplified silicon neuron of FitzHugh–Nagumo type simple for hardware realization and modification.