Inductor Energy Reduction Schemes for Overshoot Mitigation in Voltage Regulators

High current voltage regulators for microelectronic loads like microprocessors and field programmable gate arrays have stringent overshoot requirements due to reliability and performance implications. Toward this end this paper presents two novel inductor energy reduction schemes for overshoot mitigation. In first scheme inductor energy is transferred to load capacitance in a physically adjacent domain via an inter-domain switch. Results show a 40% reduction in overshoot magnitude. The second scheme eliminates inductor energy increase via a fast duty ratio clamp resulting in 22 % overshoot reduction. Both schemes save overall system power - the former via energy transfer and the latter via reduction in energy build up, thereby making them superior to conventional methods. Salient equations describing overshoot behavior, and simulation results of mitigation mechanisms for multi-domain scenarios are provided.