Design Of Single-chip Integrated Usm Driver Circuit With Built-in PLL

Motors are increasingly used in nearly every aspect of our lives,but traditional motors are difficult to achieve miniaturization and efficiency due to their own structural design and working principle.It is a certain conflict with the current development trend of portable electronic products,the appearance of Ultra Sonic Motor(USM)has filled the gap of traditional motors to a certain extent.By utilizing the inverse piezoelectric effect of piezoelectric ceramics,the friction between the stator and the rotor is converted into kinetic energy.It has the characteristics of small size,strong resistance to electromagnetic interference,and large torque.However,the demand for high drive voltages of ultrasonic motors places high demands on the miniaturization of drive circuits.In this paper,a single chip integrated USM driver chip with built-in phase-lock loop is designed and taped out.Combined with the characteristics of ultrasonic motor drive,the basic architecture of peak current mode boost circuit and two half-bridges is finally adopted,and the external input ultrasonic motor control signal is processed by the builtin phase-locked loop to generate a signal with the same frequency as the input signal,which differs by 90 °.At the same time,the two signals are used as the drive circuit output control signal to minimize the required external signals and off-chip components,and to minimize the size of the entire ultrasonic motor drive circuit.After completing the overall chip circuit and layout design and passing the simulation verification,the USM driver chip designed in this paper was taped out based on the 0.18μm BCD(Biplor-CMOS-DMOS)process.The chip test shows that the designed ultrasonic motor drive chip can successfully drive the ultrasonic motor and the key parameters meet the design requirements.In the case of testing with an ultrasonic motor,the input voltage range is 8-12 V,the Boost output voltage is 40 V,and the phaselocked loop works normally.The two half-bridges power-amplify the driving signals.After passing through the resonance network,the two channels normally output two sinusoidal signals that differ by 90 °,and the ultrasonic motor works normally.The chip test results are consistent with the simulation results,and a single-chip integrated USM driver chip design with built-in phase-lock loop is implemented.