Hybrid DC-DC Converter For Power Efficiency Improvement Operating Over a Wide Load Power

Abstract

This paper proposed hybrid converter to operate over a wide output load power. The switched-capacitor converter has a high efficiency at low load power and a low efficiency at high load power. On the contrary, the buck converter has a high efficiency at high load power and a low efficiency at low load power. The proposed hybrid converter has combination of the switched-capacitor converter and the buck converter. The switched-capacitor operates at low load power and buck converter operates at high load power, so that the hybrid converter is improved power efficiency at wide output load power. The hybrid converter was implemented with a 0.18μm CMOS process. The hybrid converter has a range of the load power between 50μW and 100mW. The maximum power efficiencies are 93% and 77% at the buck converter and the switched-capacitor converter, respectively