Design Exploration of Package-Embedded Inductors for High-Efficiency Integrated Voltage Regulators

This paper describes the modeling and design of package-embedded magnetic-core inductors for a system-in-package-based high-efficiency integrated voltage regulator. An application example is used to demonstrate the complete design process, starting with the fabrication of two candidate magnetic composite materials. Based on the measured properties of these materials, magnetic-core inductors are designed and simulated using full-wave simulations. Finally, the overall voltage regulator efficiencies resulting from inductor designs are obtained from analytical equations, which allows for rapid evaluation of different scenarios. Voltage regulator efficiency with magnetic-core inductors is seen to be considerably higher than with similarly sized air-core inductors. Notably, this is even true at high switching frequencies where the magnetic-core inductors have lower quality factors than the air-core inductor.