Mutually coupled circuits based on modified voltage differencing transconductance amplifier with tuneable characteristics

Abstract

The paper presents a new mutually coupled circuit (MCC) based on a modified voltage differencing transconductance amplifier (MVDTA), designed using the modified Gorski-Popiel technique. The proposed synthetic transformer (ST) circuit uses two MVDTAs as active elements, and all passive elements are grounded—two capacitors and two resistors. Thanks to the newly established coupling method-connections, it is provided with independent electronic control of primary and secondary self-inductance, as well as mutual inductance, via bias voltages of MVDTAs. In addition, it is very easy to provide the conditions by which symmetrical couplings are achieved. Monte Carlo analysis is carried out to verify the example application's robustness against the variation of the active and passive elements. In order to verify the results and conclusions reached through theoretical analysis, simulation testing was performed in the PSPICE software environment, both in the time and frequency domains. The functionality of the proposed MCC is shown in the example of a double-bandwidth filter (double-tuned band-pass filter [DTBP]), while in order to accurately illustrate the superiority of the proposed solution, a comparison was made with similar circuits that are known from the professional literature. The proposal is also supported by experimental results (with off-the-shelf components IC MAX435) in order to confirm the workability of the proposed solution.