Switched resonant ultrasonic power amplifier system

• US 9,768,373 B2
• Filed: 01/23/2015
• Issued: 09/19/2017
• Est. Priority Date: 10/30/2003
• Status: Active Grant

• Current Assignee: Covidien AG (Medtronic Plc)
• Original Assignee: Covidien AG (Medtronic Plc)
• Inventors: Orszulak, James H., McPherson, James W.
• Primary Examiner(s): SAINT SURIN, JACQUES M
• Application Number:
  US14/604,452
• Publication Number:
  US 20150130374A1
• Time in Patent Office: 970 Days
• Field of Search: 318116
• CPC Class Codes: A61N 2007/0056 Beam shaping elements
• CPC Class Codes: A61N 7/00 Ultrasound therapy lithotripsy A61B17/22, A61B17/225; massage using supersonic vibration A61H23/00 ; using ultrasound for introducing media into the body A61M37/0092
• CPC Class Codes: B06B 1/0253 taken directly from the generator circuit
• CPC Class Codes: B06B 1/0261 taken from a transducer or electrode connected to the driving transducer
• CPC Class Codes: B06B 2201/76 Medical, dental
• CPC Class Codes: H10N 30/802 Circuitry or processes for operating piezoelectric or electrostrictive devices not otherwise provided for, e.g. drive circuits

Abstract

A switched resonant power amplifier system for ultrasonic transducers is disclosed. The system includes an amplifier that receives and processes a driver output signal for generating a drive signal that is provided to an ultrasonic device for controlling output of the ultrasonic device. An output control circuit receives and processes a signal related to a feedback signal generated by the ultrasonic device and a divider reference signal, and generates a compensated clock signal that is adjusted for at least one of phase and frequency differences between the received feedback signal and the divider reference signal. A compensated drive circuit receives and processes the compensated clock signal for generating the divider reference signal, and for generating the driver output signal.

Claims

1. A method for controlling an output of an ultrasonic device, the method comprising:

processing first and second input signals at a phase locked loop to generate a compensated clock signal adjusted for at least one of phase or frequency difference between the first and second input signals;

generating a counter output signal based on the compensated clock signal;

splitting the counter output signal into first and second complementary square waves;

measuring at least one of the first and second complementary square waves to obtain the second input signal; and

amplifying the first and second complementary square waves to generate a driver output signal to control an ultrasonic transducer.

2. The method according to claim 1, further comprising:

receiving and processing a feedback signal related to the output of the ultrasonic transducer to generate a corresponding square wave signal; and

comparing the corresponding square wave signal to a reference signal and generating a reset signal having substantially the same frequency to the feedback signal.

3. The method according to claim 2, wherein the feedback signal is indicative of the output of the ultrasonic transducer.

4. The method according to claim 2, further comprising:

receiving and processing the reset signal to generate a compensated reference signal having a frequency that is substantially 180°

out-of-phase with respect to the reset signal.

5. The method according to claim 4, wherein the first input signal is the compensated reference signal and the second input signal is a divider reference signal.

6. The method according to claim 1, wherein generating the counter output signal further includes stepping down frequency of the compensated clock signal to generate the counter output signal.

7. The method according to claim 1, further comprising:

selectively adjusting at least one of a phase relationship between the first and second complementary signals or pulse width of pulses of the first and second complementary signals.

8. A method for controlling an output of an ultrasonic device, the method comprising:

supplying a driver output signal to an ultrasonic transducer;

processing first and second input signals at a phase locked loop to generate a compensated clock signal adjusted for at least one of phase or frequency difference between the first and second input signals;

generating a counter output signal based on the compensated clock signal;

splitting the counter output signal into first and second complementary square waves;

measuring at least one of the first and second complementary square waves to obtain the second input signal; and

amplifying the first and second complementary square waves to generate the driver output signal.

9. The method according to claim 8, further comprising:

receiving and processing a feedback signal related to the output of the ultrasonic transducer to generate a corresponding square wave signal; and

comparing the corresponding square wave signal to a reference signal and generating a reset signal having substantially the same frequency to the feedback signal.

10. The method according to claim 9, further comprising:

receiving and processing the reset signal to generate a compensated reference signal having a frequency that is substantially 180°

out-of-phase with respect to the reset signal.

11. The method according to claim 10, wherein the first input signal is the compensated reference signal and the second input signal is a divider reference signal.

12. The method according to claim 9, wherein the feedback signal is indicative of the output of the ultrasonic transducer.

13. The method according to claim 8, wherein generating the counter output signal further includes stepping down frequency of the compensated clock signal to generate the counter output signal.

14. The method according to claim 8, further comprising:

selectively adjusting at least one of a phase relationship between the first and second complementary signals or pulse width of pulses of the first and second complementary signals.