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Ladder resonant switched-capacitor converters (RSCCs) provide high step-up voltage gain, but the continuous regulation range is typically limited with an extremely wide switching frequency band. This article introduces a new full-range regulation method for step-up ladder RSCCs along with seven switching techniques. Each switching technique offers multiple possibilities for implementation. Furthermore, ladder RSCCs with the proposed switching techniques feature the merits of simple control, soft switching, and high efficiency. A comprehensive analysis of operation principle, voltage gain curves, device stress, active switch utilization, zero voltage switching range, output voltage ripple, and input current ripple is given for the proposed seven switching techniques. A 3X step-up Ladder RSCC prototype was built and tested to validate the theoretical results. [ABSTRACT FROM AUTHOR]

Multilevel resonant switched-capacitor converters (RSCCs) have drawn attention in large step-down voltage conversion but are hindered in a wide area of applications due to limited voltage regulation range. A new full-range regulation (FR) method for multilevel step-down RSCCs is proposed in this article. As an example of the proposed FR method, the fixed on-time modulation for modified Dickson RSCC is provided. In addition to full-range voltage regulation, the multilevel RSCCs with the proposed FR method feature complimentary driving signals, zero voltage switching turn-on for switches, zero current switching turn-off for diodes, even switch voltage stress, even diode voltage stress, high active switch utilization, high efficiency, and high power density. A modified Dickson RSCC prototype was built to validate the proposed FR method. The proposed FR method is further extended to series-parallel RSCCs and Fibonacci RSCCs. [ABSTRACT FROM AUTHOR]

In this article, a step-down switched-capacitor converter (SCC) and a step-up SCC with an integrated passive regenerative snubber (PRS) are proposed based on the Cuk dual resonance core (DRC). The members of the DRC converter family overcome the barrier for SCCs to achieve continuous output voltage regulation. One remaining challenge is the turn-off spikes and oscillations during the switch turn-off transient that cause voltage stress and power loss to the transistor and diode. The proposed integrated PRS eliminates voltage spikes and oscillations across the transistor and diode during the turn-off process. Moreover, zero voltage switching (ZVS) turn-on for the clamped mosfet, zero current switching (ZCS) turn-on for the other mosfet and ZCS turn-off for all diodes are achieved. A comprehensive analysis of the operation principle, conversion ratio curves, component stress, and regenerative power of the proposed converters with regenerative snubbers is given. Furthermore, a performance comparison between the proposed snubber configuration and two conventional methods is given. A 50 V/99.25 V step-up converter prototype of 125 W has demonstrated a peak efficiency of 98.4%. The analysis is verified by both simulation and experiments. [ABSTRACT FROM AUTHOR]

In this paper, a family of new step-up series–parallel dual resonant switched-capacitor converters (SP-DRSCs) is proposed to extend the conversion ratio for high step-up applications. The converters feature a wide gain range, continuously adjustable, and enhanced light-load voltage regulation. All flying capacitors operate in resonance, eliminating high transient current spikes and charge sharing losses. Thus, zero-current-switching (ZCS) turn-on for all transistors and ZCS turn-off for all diodes are achieved. A comprehensive analysis of the operation principle, voltage-gain curves, stable regulation range, and voltage and current stress is given. An analytical method to quantify the passive component volume for the group of step-up dual resonance switched-capacitor converters is presented. Further design considerations to optimize the passive component volume of the proposed SP-DRSC and the effect of bulky bypass capacitors on the volume are discussed. [ABSTRACT FROM AUTHOR]

The Cuk dual resonance core (DRC) realizes overlapped dual resonance to regulate its output voltage. However, the DRC configuration was only applied to the Fibonacci switched-capacitor converter (SCC), series–parallel SCC, and voltage doubler. In this paper, the Cuk DRC is modified and then is extended to the Dickson SCC to form a multi-resonance-core-based (MRC) Dickson resonant switched-capacitor converter. All charging and discharging loops achieve soft charging, and so the inherent capacitor charge sharing loss and the high current transient spikes are eliminated. The modular configuration makes the MRC Dickson easy to be extended to a higher voltage level. The on-time fixed frequency modulation is adopted, all transistors being turned on with zero-current-switching (ZCS) operation and all diodes being turned off with ZCS operation. Most importantly, the conversion ratio of the MRC Dickson can be regulated continuously, widely, and efficiently even at light load condition, which is a huge advantage over the traditional Dickson SCC with limited control headroom. A comprehensive analysis of the operation principle, voltage-gain curve, component stress analysis, and output characteristic is provided. The converter operation principle and regulation capability were verified by both simulation and experiment. [ABSTRACT FROM AUTHOR]

This paper proposes a new interleaved high step-up converter with coupled inductors. Interleaving configuration is employed at the input side to reduce the input current ripple and increase the power level. The series structure at the output side helps achieve a very high step-up voltage gain. Also, the proposed converter has very low switch voltage stress; thus, switching loss can be reduced and low-voltage-rating mosfets with small on resistance are allowed to lower the conduction loss. Due to the passive clamp performance, the leakage energy of the coupled inductors can be recycled and large voltage spikes across the switches are alleviated. Furthermore, with the aid of the leakage inductances, zero-current switching of the active switches can be achieved and the reverse recovery problem of the diodes is alleviated. The operating principles, performance analysis, and design considerations of the proposed converter are discussed. A prototype with 20-V input and 400-V output is built, and experimental results are provided to verify the theoretical analysis. [ABSTRACT FROM AUTHOR]

In this paper, a family of automatic interleaved Dickson switched-capacitor converters (AIDSCC) and its zero-voltage switching (ZVS) resonant configuration are proposed. Different from the traditional Dickson switched-capacitor converter, the AIDSCC has symmetrical configuration with the features of automatic interleaved input current, small output voltage ripple, and lower peak capacitor voltage stress. To improve the line regulation capability, one small resonant inductor is inserted and two bulky capacitor banks are replaced by two much smaller resonant capacitors, forming the resonant AIDSCC. The transistors are ZVS turned on and diodes are zero-current switching turned off by operating above the resonance. With frequency modulation within a reasonable range, the voltage-gain range of the resonant AIDSCC is expanded significantly, while sacrificing the maximum efficiency due to the higher conduction loss. A 3X AIDSCC and a 3X resonant AIDSCC below 140 W were built to verify the analysis. [ABSTRACT FROM AUTHOR]