Drive circuitry for driving a piezoelectric transducer, the circuitry comprising: an inductor; a first reservoir capacitor; a switch network; and control circuitry configured to control operation of the switch network to selectively couple the inductor to one of a power supply, the first reservoir capacitor and the piezoelectric transducer, wherein the circuitry is operative in a discontinuous mode to transfer charge between the reservoir capacitor and the piezoelectric transducer, and wherein a polarity of the first reservoir capacitor is opposite to a polarity of the power supply.