Novel High-Voltage Power Driver with an Active Floating Gate Bias for Medical Ultrasound Pulse Generators

The article presents a novel high-voltage power driver circuit that can be used to drive a variety of capacitive or resistive loads, applied for medical ultrasound pulse generators. The output stage of this circuit employs a pair of stacked power inverters and the novel active floating gate bias circuit, which can adaptively switch the power devices between low and high voltage conditions. Therefore, the output stage can generate rail-to-rail high-voltage signals within a safe operating range. The circuit architecture has been implemented to drive a 100-pF capacitor in parallel with a 1-K ohm resistor load. With an operating frequency of 20 kHz, the circuit can produce a three-level high-voltage pulse signal with the maximum peak-to-peak voltage of larger than 120 volts.