This paper presents LLG-SPICE, a unified circuit model for simulating planar magnetics with material physics properties. By merging the nonlinear Landau–Lifshitz–Gilbert (LLG) model for magnetic B-H hysteresis, and scaling the linear Maxwell Equation-based model for current distribution, a modular and scalable framework was created to describe the mutual correlations between the current distribution among winding stacks and the nonlinear material hysteretic characteristics. The LLG-SPICE model opens the possibility of designing and simulating high-order passive networks with coupled planar magnetic structures. It enables rapid evaluation of complex planar magnetic structures with strongly correlated circuit- and material-level behaviors, and facilitates systematic magnetic-circuit co-design for extreme miniaturization and sophisticated functions in high-performance power electronics systems.
