Low-sensitivity Filters Research Articles

A transistor realization of the generalized impedance converter

A transistor realization of a generalized impedance converter (g.i.c.) is developed from an ideal nullor representation. The use of g.i.c.s for realizing low-sensitivity RC-active filters is well established and this new circuit overcomes the requirement for using two operational amplifiers in order to realize a g.i.c. The proposed transistor realization is a single-loop structure with the practical advantage of low output impedance; the use of this circuit in the realization of typical elliptic transfer functions is considered.

Bandpass-filter realisation using gyrators

An inductorless 16–20 kHz bandpass filter has been built to test the hypothesis that low-sensitivity inductorless filters can be constructed if all the inductors in an LC filter are replaced by their gyrator-capacitor equivalents. The measured results show that this filter has low component sensitivity and excellent temperature stability and can be constructed from moderate-tolerance components.