High-efficiency multiphase DC-DC converters for powering processors with turbo mode based on configurable current sharing ratios and intelligent phase management

Efficiency is one of the key performance factors for the multiphase voltage regulators (VRs), especially for the workstation and server applications. To further improve the efficiency, a new topology by having different phase inductances in multiphase VRs is proposed in this paper. However, the phase interleaving, current sharing, and dynamic phase shedding (DPS) functions would become more challenging in this proposed topology. In order to overcome those challenges, a programmable current sharing ratio scheme is considered to improve the phase interleaving and current sharing of the proposed topology. In addition, a fast phase adding logic is also presented to improve the load transient response speed. All of these efforts aim at realizing fast transient response and high efficiency simultaneously for a multiphase VR. The simulation and experimental results show the effectiveness of the proposed topology and the control scheme.