An Interleaved Hybrid-Module Step-Up Converter With Reduction of Switching Frequency and Output Ripple

This paper proposes a series-parallel bond wire auxiliary fully integrated step-up switched-capacitor (SC) converter with conversion ratio expansion to improve the trade-off between power loss and output voltage ripple. The series-parallel switching strategy reduces the burden of delivering charges in a 1:2 SC and also extends the output-input voltage ratio range. In addition, the LBOND mismatch calibration (LMC) technique can eliminate the mismatch between bond wires. Moreover, the binary flying capacitor scaling technique automatically optimizes the capacitance of the flying capacitor to ensure a well-controlled output voltage ripple over a wide load range. With only 250pF total capacitors in use, the experimental results show a well-controlled ripple under 23.86mV and efficiency greater than 75% over a load range of 1mA to 20mA. Furthermore, this technique has a smooth efficiency profile within an input voltage level of 0.63V to 0.9V with a peak efficiency of 85% and an output voltage of 0.95V.