Novel Circuit Realizations of Neuron Activation Function and Its Derivative with Continuously Programmable Characteristics and Low Power Consumption

This paper presents novel circuit configurations to realize Neuron Activation Function (NAF) and the Derivative of Neuron Activation Function (DNAF) with low power dissipation. The circuits realize NAF and DNAF simultaneously with programmable characteristics. In the proposed configurations, tan sigmoid and log sigmoid NAFs and their derivative can be obtained from the same circuit simultaneously. Slope and threshold levels of NAF can be continuously varied and corresponding DNAF and its scaled versions can also be obtained. Monte carlo simulation of the circuit has been done to study the effect of mismatch and temperature variations. The circuits are simulated in TSPICE. Comparison with previous works and between the proposed configurations are also presented.