Passive immitance limiters

The paper presents quadripole R, L, C immittance limiters, in which output immittance to the certain value depends on the input immittance. A classification of immittance limiters is given. Basic parameters are considered: low and high levels of output immittance limiters; low and high values of input immittance, corresponding to low and high levels of limitation, accordingly; range of possible values of output immittance; steepness of immittance limiters; time of wearing-out (or delay); high and low cutoff frequencies; central working frequency; frequency band; relative range of working frequencies; non-linearity coefficient. The authors have designed passive R-, L-, C-limiters with possibility of limitation from above and from below. The influence of the input parasitic immittances on the immittance transfer characteristic is evaluated. In most cases parasite immittance does not influence the considered devices, including R-limiters «from above» with the input quality factor of QR(Linp)=0,1…0,2 and L-limiters «from above» with high-quality input circuits with QL(Rinp)>2. The analysis also shows that high-qualitiy circuits with QN(RinpN)>3 should be used in C-limiters with input parasitic immittances, while at parasitic immittance of the limiting element low-quality circuits with QN(RiN)>0,2 should be selected