Romeo Ghinea, Liviu Goras, Tecla Goras, TUIASI, Iasi, Romania
Michael Ansorge, University of Neuchatel (UniNE), Neuchatel, Switzerland
SYNCHROINFO JOURNAL. Volume 8, Number 1 (2022). P. 14-19.
The nonideal behaviour of astable multivibrators based on Negative Impedance Converter (NIC) type configuration is approached taking into consideration several nonidealities among which the slew-rate of the voltage operational amplifier (OA). Linear conversion of inductances, capacitances and resistances into time period is useful to measure impedances or physical quantities by means of impedance-type transducers. Following a series of investigations on this topic, a thorough study of four configurations for linear inductance-time and capacitance-time conversions based on the astable multivibrator viewed as a NIC-type nonlinear oscillator. Four circuits were studied, two of them having grounded reactive elements. The results can be used for linear capacitance-to-time (C|T) and inductance-to-time (L|T) conversions.
Keywords: Negative Impedance Converter, operational amplifier, capacitance-to-time, inductance-to-time.
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