A Systematic Modeling Methodology for RF Capacitors and Inductors

Accurate modeling of RF capacitors and inductors is critical for predicting circuit behavior and ensuring operational robustness in high-frequency electronic systems. However, SPICE models are often unavailable from manufacturers, and there is still a lack of reliable methodologies for accurate modeling of such passive components over a wide frequency range. This paper presents a systematic and practical equivalent-circuit modeling methodology for capacitors and inductors based on measured impedance data. The proposed approach partitions the entire frequency range into multiple sub-bands and models each using a combination of a core series RLC network and frequency-dependent parallel RC, RL, and RLC sub-networks. This piecewise construction enables the dominant resistive, inductive, and capacitive behaviors to be independently identified and accurately captured in their respective frequency regions, resulting in an accurate broadband equivalent circuit. The resulting models exhibit excellent agreement with target data, demonstrating the reliability of the method. This work provides a practical and systematic procedure for developing accurate broadband models of RF passive components, with validation demonstrated for capacitors up to 6 GHz and inductors up to 20 GHz.