A semiconductor device includes a first integrated circuit chip, a second integrated circuit chip, a coupled inductor system, and a semiconductor package. The first integrated circuit chip is connected to a substrate and configured to process digital data. The second integrated circuit chip is configured to manage power for the first integrated circuit chip. The coupled inductor system is embedded in the substrate, connected to the second integrated circuit chip, and has a first inductor configured to be magnetically coupled to a second inductor. The semiconductor package is configured to encapsulate the first integrated circuit chip and the second integrated circuit chip.