Restriction on realization of single‐amplifier impedance‐converter and its application to LCR filter simulation

This paper proposes a method to realize single-amplifier impedance converters (SAICs), while a conventional general impedance converter (GIC) for an active RC filter requires two operational amplifiers. First, various restrictions required for realizing an SAIC were investigated. Then a method of realizing an SAIC was described which utilizes the property of a grounded active RC two-port circuit having an impedance-conversion effect; and the SAIC was applied to the simulation of an LCR filter. an SAIC can approximately simulate an arbitrary circuit with some restricted circuit constants, although the range of circuits which can be simulated exactly is limited. As examples, an asymmetrical sixth-order BPF and a symmetrical sixth-order BPF were constructed and their experimental results agreed well with the theoretical values.