Reconfigurable versatile temperature-insensitivity immittance simulators with electronic tunability using commercially available ICs

This paper presents novel reconfigurable and electronically tunable immittance simulators using commercially available LT1228 integrated circuits. The proposed circuits simulate four fundamental impedance functions, which are a resistor, a capacitor, an inductor, and a frequency-dependent negative resistor (FDNR) within the same topology. The proposed simulators use only two or three LT1228 ICs and three passive components to provide grounded and floating types, be compact, and function in a variety of ways. A significant contribution of this work is the development of an impedance expression that does not depend on temperature. This makes sure that performance stays stable over a wide range of temperatures without the need for external compensation techniques. The proposed circuits offer linear electronic control via bias currents, enabling precise and dynamic tuning of the simulated element values. Moreover, the proposed simulators can be configured to four lossless impedance functions without needing the matching conditions of passive elements. A study of the parasitic effect is also conducted to assess accuracy and useful frequency range of the proposed configuration. Both grounded and floating configurations are realized and validated through simulation and experimental results. A third-order low-pass ladder filter and a multifunction second-order filter are designed to show the applications of the proposed simulators. The accuracy, reconfigurability, and temperature stability of the proposed circuits are confirmed by the simulation and experimental results, which make them ideal for modern analog signal processing applications. Temperature stability is verified via PSpice simulation over –100 °C to + 100 °C, showing less than 1 % variation, while impedance accuracy and filter applications are confirmed experimentally.