Dual Voltage Input Reconfigurable VR for Improving Light-Load Efficiency

Extended battery life requirements for portable systems have driven innovation in power management techniques resulting in very low loads on power conversion circuits. The problem of low power conversion efficiency of typical buck converters at very light load conditions will be explained. The need for extremely high conversion efficiencies to deliver truly mobile systems will be outlined. A dual voltage input reconfigurable voltage regulator (VR) topology for handheld applications will be proposed as a solution to achieve high conversion efficiencies over a wide load range. Analytical and experimental results with a conventional buck topology will be presented to show the benefits of reconfiguring the VR topology based on load demands