A Monolithic Quasi-Resonant Switched-Capacitor Converter with Dual-Loop Time-Based Controller

Resonant switched-capacitor converters provide high peak efficiency and small area occupation compared to standard inductive-based step-down converters. To enable point-of-load regulation, quasi-resonant control can be used. This control technique changes the energy delivered to the output by modulating the phase shift of the switched-capacitance driving signals. No modification of the power stage topology is needed, thus preserving the converter power density. In this paper, a three-phase quasi-resonant control using a time-based implementation is presented. The proposed circuit exploits a dual-loop control strategy by using a single controller: this is achieved by modulating the common mode and the differential mode of voltage-controlled oscillators. The controller is designed using BCD technology with 180nm CMOS, and its dynamic performance is verified through SIMetrix/SIMPLIS simulations.