20.2 A variable-conversion-ratio 3-phase resonant switched capacitor converter with 85% efficiency at 0.91W/mm2 using 1.1nH PCB-trace inductors

Switched-capacitor (SC) converters have shown significant promise for monolithic integration in a variety of mobile computing applications due to the relatively high energy-densities of modern capacitor technologies and the emergence of deep-trench technology [1-4]. Compared to more traditional buck and boost topologies, the SC approach provides better utilization of active and passive components, and is especially favorable when using submicron or deep-submicron CMOS technology because low-voltage devices can be configured in cascaded or hierarchical structures to interface across wide conversion ratios [5].