Due to their high power density and appropriateness for small circuits integration,\nswitched-capacitor (SC) converters have gotten more interests. Applying the soft-charging technique\neffectively eliminates the current transient that results in a higher power density and a higher\nfundamental efficiency. Achieving the complete soft-charging operation is impossible by using the\nconventional control diagram for any SC converter topology. In this paper, we proposed a split-phase\ncontrol to achieve the complete soft-charging operation in a power switched-capacitor (PSC) converter.\nThe proposed control diagram was designed for a 1-to-4 PSC converter (two-level of the PSC converter).\nThe implemented split-phase diagram successfully controls eight switches to exhibit eight modes\nof operation. In addition to the current transient elimination, the complete soft-charging allows us\nto reduce capacitor sizes. However, reducing capacitor size negatively increases the output voltage\nripple; hence, an output LC filter is needed. The complete soft-charging achievement accomplishes\na 96% efficiency due to the lower output impedance and the dead time switching. LT-Spice software\nhas been used to verify the proposed control and the results were compared with hard-charging and\nincomplete soft-charging operations.
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