Dynamic Matching Model of Ultrasonic Transducer Based on Digital Inductance

Ultrasonic bonding is a process to achieve the IC chip connection, which makes it to be the mail typical package style. The impedance matching between the ultrasonic transducer and the electrical driver is the basic problem, which will determine the energy transform efficiency of the ultrasonic transducer. A novel dynamic matching method based on the digital inductance used in the electrical driver is introduced in this paper. Firstly, the necessary for the dynamic matching of the ultrasonic system is proved by the equivalent model of the transducer. In the Matlab simulation calculation, it is verified that the phase between the voltage and current will be zero with the correct match inductance. If the impedance of the transducer is changed, the match inductance is also tailed to ensure the zero phase according to the equivalent model. Then, the hardware system is built to verify the theory model, where an ARM microcomputer, DDS signal, and the digital inductance are used. Finally, the experiments are carried out to validate the equivalent model and the Matlab simulation.