Design Of The H-bridge Circuit Of A Monolithic Ultrasonic Motor Driver

As the miniaturization of embedded electronic devices and high-precision electromechanical goes on,the demand of micro-motor and its minimature driver is increasingly strong.Ultrasonic motor is an ideal micro-motor which has the advantage of small size,high torque,fast response,etc.But it's difficult to reduce the size of ultrasonic motor driver due to the high requirement of output voltage.However,the combination of HVIC process and low-operating-voltage ultrasonic motor made monolithic,transformerless ultrasonic motor driver possible.To design a monolithic ultrasonic motor driver IC,this paper presents an H-bridge circuit for ultrasonic motor driver IC based on 0.35?m BCD process with maximum operating voltage of 40 V.High voltage LDMOS devices are used power switches,thus ultrasonic motor with operating voltage of 40 V or lower.Two independent half bridges are integrated into a single chip with flexible input signal frequency,phase parameters adjusted by the external source.To minimize the size of the ultrasonic motor drive system,the H-bridge circuit is designed to work without any external devices.In this thesis,the design of the H-bridge circuit is discussed.The circuit utilize a dead-time control method with adaptive and fixed time interval,an optimally designed gate driver structure,a low-power-consumption level shifter,and acap less voltage regulator for high-side gate driver with adaptive bias current and real-time switching compensation.The designed H-bridge circuit is taped-out and tested,which has 0-3MHz output frequency range and minimum quiescent supply current of only 80?A.