Comprehensive Reliability Review and Assessment of Switched-Capacitor Step-Up DC–DC Converters

Abstract

Due to the deficiencies of the traditional pulsewidth modulation dc–dc boost converter to achieve high voltage gain values, many capacitive and magnetic approaches have been suggested. As a promising solution, the switched-capacitor (SC) cells are employed to increase the voltage boosting capability, even at low/medium duty cycles, which accordingly removes the concerns originated from components' parasitic elements. In the literature, comprehensive investigations have been performed on the traditional SC boost converters from different viewpoints of step-up capability, efficiency, number of components, design considerations, and cost. Meanwhile, several papers investigate the reliability of boost converters only at a fixed operating point, but the extensive reliability analysis of these converters is still missed. This article provides comprehensive investigations on the effects of different operational or design parameters, such as input voltage, duty cycle, gain, switching frequency, output power, load resistance, and lifetime on the reliability of the traditional SC boost converters as well as their failure rate sensitivity. Based on the provided results, the maximum reliability can be accomplished by choosing optimal values for the converters' operational or design parameters. The provided theoretical analysis has been confirmed by the simulation and experimental results.