New design for current-mode rational-powered membership function generator

This paper presents new approximations for the rational-powered membership function generator. These approximations require only a squaring function, a scalar function and a constant. Thus, the realization of the rational-powered function in current-mode is simple, straightforward and uses less number of MOSFETs. Simulation results obtained show that the rational-powered function can be obtained with root mean square (RMS) error less than 0.03 over the normalized input range 0-1 and for a wide range of rational powers. Much less RMS errors can be obtained if the normalized input values are restricted.