Inductorless Step-Up Piezoelectric Resonator (SUPR) Converter: A Describing Function Analysis

A model for an inductorless step-up piezoelectric-resonator-based dc–dc converter is presented. A describing function approach is used to determine the equivalent circuit of the
mosfet
power stage and resonator, allowing the duty cycles of both
mosfet
s to be accurately estimated. The model provides a method for estimating the output voltage and resonant current of the converter during operation. The accuracy of the model is verified against experimental and simulation results, with a less than 1.5% mean absolute percentage error in voltage gain estimation, compared with experimental measurements. Design guidelines for optimal operation of the converter are also presented.