US Patent 10497358 Transducer driver

A circuit for driving a transducer in a mid-air haptic system includes a voltage source, a voltage sink, a current source, a trickle capacitor, a storage capacitor, a haptic system transducer, a first switch, a second switch, and a third switch. Using these components, a portion of the charge required for switching a transducer is sourced from the decoupling capacitance. When the switching completes, additional charge is transferred immediately from the power supply back into the decoupling capacitance. This acts to lower the peak current by fully utilizing 100% of a switching waveform for transfer of charge from the power supply to capacitors local to the transducer.