A Magnetostatic Model for Square Spiral Inductors Incorporating a Magnetic Layer

Embedding magnetic layers in inductors is an attractive option for increasing inductance density, which is a critical issue for radio-frequency applications. In this letter, we develop a magnetostatic model for square spiral inductors incorporating a magnetic layer. In our model, we assume that the permeability of the magnetic layer is isotropic and infinite. The model provides a fast and effective numerical calculation of the inductance of inductors incorporating a magnetic layer. We show the derivation of the model and provide calculation results for various inductor structures.