Title :
New general immittance converter JFET voltage-controlled impedances and their applications to controlled biquads synthesis
Author :
Leuciuc, Adrian ; Goras, Liviu
Author_Institution :
Dept. of Electron. & Telecommun., Tech. Univ. of Iasi, Romania
fDate :
6/1/1998 12:00:00 AM
Abstract :
Two new general immittance converter (GIC) JFET configurations for the realization of voltage-controlled impedances (VCI´s) are proposed. Compared with previously reported structures, the circuits exhibit wide dynamic range and low distortion properties that are frequency independent, even for nonresistive VCI´s. We consider the influence of op-amp frequency dependent gain and derive conditions for obtaining high Q-factor inductances and capacitances. We also present computed and experimental results for several voltage-controlled GIC-type biquads that are built based on the proposed circuits
Keywords :
JFET circuits; Q-factor; active networks; biquadratic filters; network synthesis; operational amplifiers; GIC-type biquads; JFET voltage-controlled impedances; controlled biquads synthesis; general immittance converter; high Q-factor capacitances; high Q-factor inductances; low distortion properties; op-amp frequency dependent gain; wide dynamic range; Active filters; Capacitance; Circuit synthesis; Computational modeling; Dynamic range; Frequency dependence; Impedance; Nonlinear distortion; Operational amplifiers; Voltage control;
Journal_Title :
Circuits and Systems I: Fundamental Theory and Applications, IEEE Transactions on