Ultrasonic operation apparatus for performing follow-up control of resonance frequency drive of ultrasonic oscillator by digital PLL system using DDS (direct digital synthesizer)

摘要

An ultrasonic operation system includes a handpiece having an ultrasonic transducer, which treats a living tissue using ultrasonic oscillations. The system includes a driving signal oscillator for producing a driving signal for driving the ultrasonic transducer and supplying the driving signal to the handpiece; a sweep circuit for sweeping a frequency of the driving signal; a data transfer circuit for transferring start frequency data to the sweep circuit to start sweeping the frequency of the driving signal; a detection circuit for detecting a resonance frequency of the handpiece based on the driving signal of which the frequency has been swept by the sweep circuit; and a chase lock loop (PLL) circuit for locking the frequency of an output current onto the resonance frequency; and, a switch for switching between the PLL circuit and the sweep circuit according to a detection result from the detection circuit.