Finite Element Model in LTspice of a Distributed RC-Structure Fractional-Order Capacitor Device

• Published in: Proceedings of IEEE Southeastcon pp. 1494 - 1500
• Main Authors: Prokup, Lauryn A., Kubanek, David, Freeborn, Todd J.
• Format: Conference Proceeding
• Language: English
• Published: IEEE 22.03.2025
• Subjects: Capacitors; Circuits and systems; Design methodology; Equivalent circuits; Finite element analysis; Integrated circuit modeling; Logic gates
• DOI: 10.1109/SoutheastCon56624.2025.10971518

Fractional-order capacitors can potentially be fabricated using MOS technologies taking advantage of their distributed resistive-capacitive structure. However, there are limited models to simulate the characteristics of these designs. In this work, an equivalent circuit model to represent a finite-element of a MOS structure is used to assemble a hierarchical model of a complete design in LTspice. This equivalent circuit model is validated (for designs with phases of -77°, -74°, -58°, and -53° with a maximum of ±2° tolerance) against previously established matrix model representations. Using this validated model varying gate length connections (from 100% to 6.25%) caused deviations less than 0.25° supporting that this characteristic of MOS technologies is not likely to have a significant effect on fabricated designs.