Aiming at the problem that the tracking frequency range of ultrasonic power is fixed, and the accuracy of tacking frequency is low, the tactics of digital phase-locked loop frequency tracking technology combined with changing step searching circuit peak is proposed. The frequency tracking is achieved by combining the advantages of digital phase-locked loop frequency tracking technology with changing step searching circuit peak, building the digital phase detector circuit and current effective value converter circuit, taking the feedback of sampling the phase and circuit peak as basic of frequency tracking. Build the simulating model in Multisim. The experiment results show that composite frequency tracking strategy can effectively achieve frequency tracking and dynamically lock transducer multi-modal resonance.
Design of All Digital Phase Locked Loop for Wireless Applications