A Building Block IC for Designing Emerging Hybrid and Multilevel Converters

This paper introduces a practical power management integrated circuit (IC) building block, i.e., IC module, which enables the implementation of various emerging hybrid and multilevel power converter topologies in low-power highfrequency applications, operating at switching frequencies up to 10 MHz. Compared to conventional buckand boost-based topologies, the emerging multilevel and hybrid converters offer significant volume reduction and power processing efficiency improvements. These key factors are significant contributions for modern portable and/or small footprint electronics devices, where size is of great concern. The IC building block (ICBB) consists of two segmented half bridges as well as all the elements needed for implementing mixed-signal current programmed mode (CPM) control. Mixed-signal CPM compatibility coupled with a segmented power stage not only provide inherent current protection and simple controller implementation but also allows for dynamic efficiency optimization. Operation at high-switching frequencies and simple modular design with ICBB are enabled through the development of novel architectures for key functional blocks of the ICBB and a cost-effective solution for level shifting, providing communication between external control signals and module inputs. For example, solutions for high-frequency low-power current sensing and fast digital-to-analog conversion are introduced as well as a capacitive coupling and coding schemes for data transfer. Several identical custom-designed ICBB modules are fabricated in the 0.13-μm CMOS process, each providing up to 2 W of output power, while operating at a switching frequency of up to 10 MHz. The versatility and proper functionality of these modules are verified through simulation and experimental results.