Electrosurgical ultrasonic vessel sealing and dissecting system

An ultrasonic surgical apparatus for treating tissue, comprising:

• a power source configured to output direct current (DC);
• an ultrasonic motion generator electrically coupled with the power source, the ultrasonic motion generator including:
• a non-resonant inverter configured to invert the DC to alternating current (AC) having a first frequency;
• an ultrasonic transducer configured to generate an ultrasonic motion based on the AC;
• a motional sensing circuit electrically coupled with the ultrasonic transducer in parallel, the motional sensing circuit including a capacitor, a first resistor in series with the capacitor, and a second resistor in parallel with the capacitor and the first resistor and in series with the ultrasonic transducer, wherein the motional sensing circuit is further configured to sense a motion current passing though the ultrasonic transducer;
• and
• a comparator configured to automatically detect a deviation of the first frequency from a resonant frequency of the ultrasonic transducer based on the motion current and to generate an output signal based on the deviation to drive the non-resonant inverter;
• and
• a controller coupled with the motional sensing circuit and the comparator, and configured to control an amplitude of the DC.

An ultrasonic system for treating tissue, comprising:

• a ultrasonic surgical apparatus including:
• a power source configured to provide direct current (DC);
• an ultrasonic motion generator electrically coupled with the power source, the ultrasonic motion generator including:
• a non-resonant inverter configured to invert direct current (DC) to alternating current (AC) having a first frequency;
• an ultrasonic transducer configured to generate an ultrasonic motion based on the AC;
• a motional sensing circuit electrically coupled with the ultrasonic transducer in parallel, the motional sensing circuit including a capacitor, a first resistor in series with the capacitor, and a second resistor in parallel with the capacitor and the first resistor and in series with the ultrasonic transducer, wherein the motional sensing circuit is configured to sense a motion current passing though the ultrasonic transducer;
• and
• a comparator configured to automatically detect a deviation of the first frequency from a resonant frequency of the ultrasonic transducer based on the motion current and to generate an output signal based on the deviation to drive the non-resonant inverter;
• a sensor configured to sense the DC passing from the power source to the ultrasonic motion generator;
• and
• a controller coupled to the sensor and the comparator, and configured to control an amplitude of the DC;
• and
• an end effector configured to apply the generated ultrasonic motion to tissue for treating the tissue.