Design of High Efficiency Integrated Voltage Regulators with Embedded Magnetic Core Inductors

Integrated voltage regulators (IVRs) are one of the main trends in power delivery networks (PDNs) for electronic systems. A major challenge in the IVR design is to achieve sufficient integration / minimization of the required passive components of the IVR while still maintaining high power efficiency. This paper demonstrates that a buck converter type IVR designed with package embedded magnetic core inductors can achieve a very high efficiency with a substantially reduced area requirement compared to "air core" inductors. For the final design, an analytical evaluation shows 91% power efficiency for a 1.7V:1.05V conversion. Moreover, a stacked topology of the power stage allows a direct 5V:1V conversion at 79.4% efficiency eliminating the need for a separate off-package voltage regulator.