Power conversion is crucial to most electronic systems due to different voltage levels requirement within the system. Switched-capacitor converters are a subset of switching modeconverters, where the energy is transferred from the input to the output using only capacitors and switches. SC converters provide compact solution due to its magnetic-less structure,which makes them ideal to fulfill the high density requirement in low power applications. Inliterature, Dickson SC converter is considered a good candidate for low power applicationscompared to other SC topologies. Yet, Fibonacci SC (FSC) topology can be competitivedue to their minimum area requirement and relatively good efficiency performance. In addition, FSC provides the highest voltage-conversion-ratio (VCR) using the least number ofcomponents, and hence can be useful in high gain applications. Therefore, the main goal ofthis dissertation is to introduce FSC as a viable solution for low power applications. Thisdissertation contributes in three domains: (1) SC theory, (2) FSC synthesis and (3) FSCdesign and implementation.For the first part, the well-known SC fundamental limit theory, proposed in 1995 by MarkS. Makowski et al, is revisited. This theory sets the VCR boundaries for a specific numberof k flying capacitors in a SC converter. Although this limit is valid for the positive VCR,we found that another condition must be satisfied for the negative VCR. As a result, wepropose a generalized version of the theory to overcome these limitations, which establishesthe foundation for the rest of the work in this dissertation. Second part of the dissertationexplores the FSC synthesis problem. In fact, synthesizing nonlinear SC converters like FSCto achieve certain/multiple VCR is not trivial, and usually performed using ad-hoc approach.Therefore, an efficient algorithm to address the SC synthesis problem is proposed, which ismade available as an open-source tool, called FSC Synthesizer, to promote the use of FSC.The proposed tool is verified by implementing FSC converter that achieves four VCRs.Finally, the design procedure and analysis of a variable FSC converter is investigatedin both, discrete and on-chip implementation. For the first part, discrete FSC design isstudied, and a prototype for a variable FSC is built and tested. The PCB occupies an area of2.7inch2, which includes the controller and FSC. The adaptive VCR technique is employed toregulate the output voltage. For 300-600mV input voltage, the proposed converter provides amean output voltage of almost 1.46V with a 2:67% discrepancy from 1.5V nominal designedvoltage. For the second part, the on-chip integration challenges including parasitic chargeloss and start-up from low voltage, are studied. A charge recycling technique exploiting thepresence of parasitic capacitors in each other phase of FSC converter has been employedresulting in 27% reduction in the power loss, which improves the overall efficiency by 12:7%.For a proof-of-concept, a monolithic FSC is implemented in 0:5μm CMOS technology on4mm2 die area. The post-layout simulation is carried out using Virtuoso ADE. With 0.3Vinput voltage, the system achieves 47:5% peak power efficiency with 5μW load
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