Modeling and implementation of high-gain switched-inductor switched-capacitor converter

This paper presents the modeling & implementation of a closed-loop high-gain switched-inductor switched-capacitor converter (SISCC) for step-up DC-DC conversion & regulation. The power part of SISCC consists of two cascaded blocks: (i) Front: a serial-parallel switched-capacitor (SC) circuit with nc pumping capacitors, and (ii) Core: a switched-inductor (SI) booster with mc resonant capacitors, so as to boost the step-up gain up to (nc+1)x(mc+1) at most, where D is the duty cycle of pulse-width-modulation (PWM) control. The control part of SISCC is composed of a phase generator and PWM controller, mainly implemented in the chip (I.C. number: D35-101B-37e, TSMC 0.35μm 2P4M, size: 500μm×300μm, 12.2mW, max. frequency: 200kHz) via full-custom fabrication of National Chip Design and Implementation Center (CIC), Taiwan. Some theoretical analysis includes: formulation, steady-state analysis, and conversion ratio. Finally, the performance of this scheme is verified experimentally on a SISCC prototype, and the results are illustrated to show the efficacy of this scheme.