Demonstration of Synaptic Connections with Unipolar Junction Transistor based Neuron Emulators

Abstract

Neuron emulator circuits can be used for teaching and proving concepts. Such emulators should be made with cheap and off-the-shelf components. There are bipolar and MOSFET transistor-based neuron emulator circuits heavily used in literature. Opamp-based neuron emulators are also commonly used. Such circuits provide simple and cheap solution instead of using microcontroller-based neuron emulators if many neurons are to be used in the studies such as showing circadian resonance. Unipolar junction transistor (UJT) is commonly used in industrial electronics applications. It provides a cheap timing circuit. Although there are a few UJT-based artificial neuron patents, we were unable to find research articles on UJT-based artificial neurons. In this study, we examined a simple network of UJT-based artificial neurons and show their spiking and bursting behavior with synaptic connections between neurons. It is shown that the firing rate of a UJT-neuron can be increased by utilizing spikes generated by another one with simulations. This behavior represents excitatory connectivity between two neurons.