An impedance matching circuit is provided for use with a piezotransducer that includes a parasitic capacitor comprising: an inductor coupled in parallel with the parasitic capacitor; a peak and valley detection circuit configured to detect output voltage waveform peaks and valleys; a first switch circuit configured to bias flip the output voltage waveform at a selectable first time relative to a detected peak and at a selectable first time relative to a detected valley; a second switch circuit configured to couple the inductor to the energy storage circuit at a selectable second time following each output voltage bias flip; an energy monitoring circuit to provide an indication of energy flow from the inductor to the energy storage circuit following each output voltage bias flip; and a maximum power point tracking (MPPT) circuit configured to select the first time and the second time based at least in part upon the indicated energy flow.