Traditional lumped parameter circuit theory faces challenges in impedance analysis of chip inductors 1

The Challenges Faced by Electronic Circuit CAD in High-Frequency Circuit Analysis

As the operating frequency of RF circuits continues to increase, the performance characteristics of chip inductors in applications have undergone significant changes, beginning to exhibit the operational properties of the low-end microwave frequency band. Therefore, to effectively enhance the electrical parameters of chip inductors and improve the performance of RF circuits, it is essential to further analyze the distinct patterns of their low-frequency and high-frequency characteristics.diode

On the other hand, the continuous innovation of communication systems (GSM, CDMA, PCS, 3G, etc.) has gradually increased the operating frequency of chip inductors to 2GHz or even higher. Consequently, the traditional lumped parameter circuit theory has shown increasingly evident limitations in analyzing the impedance of chip inductor devices.

Impedance analysis:

The physical significance of an inductor is to store alternating magnetic field energy using a conductive wire coil. In practical circuit applications, the primary function of inductor components is to provide the necessary inductive impedance to the circuit, enabling the fulfillment of corresponding circuit functions (matching, filtering, oscillation, etc.) in conjunction with other related components. Common chip inductor types include multilayer chip, wound chip, and photolithographic thin-film forms, each differing in manufacturing processes and internal electrode structures. However, under medium to low-frequency conditions, where the signal wavelength far exceeds the device dimensions, the circuit response of the inductor is minimally influenced by the internal electrode structure. Consequently, a lumped parameter equivalent model can typically be used to approximate the impedance characteristics of chip inductors. Based on this, the functional expressions for commonly used electrical performance parameters can be derived.diode