A fully integrated, wide-load-range, high-power-conversion-efficiency switched capacitor DC–DC converter with adaptive bias comparator for ultra-low-power power management integrated circuit

In this paper, we present a wide-load-range switched-capacitor DC-DC buck converter with an adaptive bias comparator for ultra-low-power power management integrated circuit. The proposed converter is based on a conventional one and modified to operate in a wide load range by developing a load current monitor used in an adaptive bias comparator. Measurement results demonstrated that our proposed converter generates a 1.0 V output voltage from a 3.0 V input voltage at a load of up to 100 mu A, which is 20 times higher than that of the conventional one. The power conversion efficiency was higher than 60% in the load range from 0.8 to 100 mu A. (C) 2018 The Japan Society of Applied Physics.