Generator for digitally generating electrical signal waveforms for electrosurgical and ultrasonic surgical instruments

• US 10,194,973 B2
• Filed: 09/07/2016
• Issued: 02/05/2019
• Est. Priority Date: 09/30/2015
• Status: Active Grant

• Current Assignee: Cilag Gmbh International (Johnson & Johnson)
• Original Assignee: Ethicon, LLC (Johnson & Johnson)
• Inventors: Wiener, Eitan T., Yates, David C.
• Primary Examiner(s): Hiltunen, Thomas J
• Application Number:
  US15/258,569
• Publication Number:
  US 20170090507A1
• Time in Patent Office: 881 Days
• CPC Class Codes: A61B 18/1206 Generators therefor
• CPC Class Codes: A61B 18/1445 at the distal end of a shaft, e.g. forceps or scissors at the end of a rigid rod
• CPC Class Codes: A61B 18/1482 having a long rigid shaft for accessing the inner body transcutaneously in minimal invasive surgery, e.g. laparoscopy
• CPC Class Codes: A61B 2017/00017 Electrical control of surgical instruments
• CPC Class Codes: A61B 2017/00137 Details of operation mode
• CPC Class Codes: A61B 2017/0015 applied simultaneously
• CPC Class Codes: A61B 2017/320094 additional movable means performing clamping operation
• CPC Class Codes: A61B 2018/00642 with feedback, i.e. closed loop control
• CPC Class Codes: A61B 2018/00994 combining two or more different kinds of non-mechanical energy or combining one or more non-mechanical energies with ultrasound
• CPC Class Codes: A61B 2018/1273 including multiple generators in one device
• CPC Class Codes: A61B 2018/128 generating two or more frequencies
• CPC Class Codes: A61B 2018/1293 having means to prevent interference
• CPC Class Codes: B06B 1/0207 Driving circuits specially adapted for particular applications, see the relevant subclass, e.g. G01; circuits for steering transducer arrays G10K11/34; basic circuits H03
• CPC Class Codes: G06F 1/022 Waveform generators, i.e. devices for generating periodical functions of time, e.g. direct digital synthesizers G06F1/025, G06F1/03 take precedence
• CPC Class Codes: H03K 5/01 Shaping pulses discrimination against noise or interference H03K5/125

Abstract

Disclosed is a method of generating electrical signal waveforms by a generator. The generator includes a digital processing circuit, a memory circuit in communication with the digital processing circuit, the memory circuit defining a lookup table, a digital synthesis circuit in communication with the digital processing circuit and the memory circuit, and a digital-to-analog converter (DAC) circuit. The method includes storing, by the digital processing circuit, phase points of a digital electrical signal waveform in the lookup table defined by the memory circuit, wherein the digital electrical signal waveform is represented by a predetermined number of phase points, wherein the predetermined number phase points define a predetermined wave shape. Receiving a clock signal by the digital synthesis circuit. Retrieving, by the digital processing circuit, a phase point from the lookup table. Converting, by the digital processing circuit, the retrieved phase point to an analog signal.

Claims

1. A method of generating electrical signal waveforms by a generator, the generator comprising a digital processing circuit, a memory circuit in communication with the digital processing circuit, a digital synthesis circuit in communication with the digital processing circuit and the memory circuit, and a digital-to-analog converter (DAC) circuit, the memory circuit defining a lookup table, the method comprising:

storing, by the digital processing circuit, phase points of a digital electrical signal waveform in the lookup table defined by the memory circuit, wherein the digital electrical signal waveform is represented by a predetermined number of phase points, wherein the predetermined number of phase points define a predetermined wave shape; and

receiving a clock signal by the digital synthesis circuit, and at each clock cycle;

retrieving, by the digital processing circuit, a phase point from the lookup table; and

converting, by the DAC circuit, the retrieved phase point to an analog signal; and

receiving, by the digital processing circuit, a feedback signal associated with a tissue parameter; and

modifying, by the digital processing circuit, the predetermined wave shape according to the feedback signal.

2. The method of claim 1, comprising amplifying, by an amplifier, the analog signal from an output of the DAC circuit.

3. The method of claim 1, wherein storing, by the digital processing circuit, phase points of the digital electrical signal waveform in the lookup table defined by the memory circuit, comprises:

storing, by the digital processing circuit, phase points of multiple digital electrical signal waveforms in corresponding multiple lookup tables defined by the memory circuit or other memory circuits, wherein each of the digital electrical signal waveforms is represented by a predetermined number of phase points, and wherein each of the predetermined number of phase points defines a different wave shape.

4. The method of claim 1, comprising:

at each clock cycle;

converting, by the DAC circuit, a modified phase point of the predetermined number of phase points that define a modified predetermined wave shape, to an analog signal.

5. The method of claim 1, wherein the digital electrical signal waveform represents a RF signal waveform, an ultrasonic signal waveform, or a combination thereof.

6. The method of claim 1, wherein the digital electrical signal waveform represents a combination of two waveforms having different amplitudes.

7. The method of claim 1, wherein the digital electrical signal waveform represents a combination of two waveforms having different frequencies.

8. The method of claim 7, wherein the digital electrical signal waveform represents a combination of two waveforms having different amplitudes.

9. The method of claim 1, wherein the predetermined wave shape is a trapezoid, a sine or cosine wave, a square wave, a triangle wave, or any combinations thereof.

10. The method of claim 1, wherein the digital electrical signal waveform is a combined RF and ultrasonic signal waveform configured to maintain a predetermined ultrasonic frequency.

11. The method of claim 1, wherein the digital electrical signal waveform is a combined RF and ultrasonic waveform configured to deliver a maximum power output.

12. A method of generating electrical signal waveforms by a generator, the generator comprising a digital processing circuit, a memory circuit in communication with the digital processing circuit, a digital synthesis circuit in communication with the digital processing circuit and the memory circuit, and a digital-to-analog converter (DAC) circuit, the memory circuit defining first and second lookup tables, the method comprising:

storing, by the digital processing circuit, phase points of a first digital electrical signal waveform in the first lookup table defined by the memory circuit, wherein the first digital electrical signal waveform is represented by a first predetermined number of phase points, wherein the first predetermined number of phase points define a first predetermined wave shape;

storing, by the digital processing circuit, phase points of a second digital electrical signal waveform in the second lookup table defined by the memory circuit, wherein the second digital electrical signal waveform is represented by a second predetermined number of phase points, wherein the second predetermined number of phase points define a second predetermined wave shape; and

receiving, by the digital synthesis circuit, a clock signal, and at each clock cycle;

retrieving, by the digital synthesis circuit, a phase point from the first lookup table;

retrieving, by the digital synthesis circuit, a phase point from the second lookup table; and

determining, by the digital processing circuit, whether to switch between the phase points of the first and second electrical signal waveforms or to synchronize the phase points of the first and second electrical signal waveforms.

13. The method of claim 12, comprising receiving, by the digital processing circuit, a feedback signal associated with tissue parameters.

14. The method of claim 13, comprising:

switching between the phase point of the first digital electrical signal waveform and the phase point of the second digital electrical signal waveform; and

converting, by the DAC circuit, the retrieved phase points.

15. The method of claim 12, comprising:

synchronizing the phase points of the first and second digital electrical signal waveforms to maximize power delivery per cycle; and

converting, by the DAC circuit, the synchronized phase points.

16. The method of claim 12, wherein the first digital electrical signal waveform represents a RF waveform and the second digital electrical signal waveform represents an ultrasonic signal waveform.

17. A generator for generating electrical signal waveforms, the generator comprising:

a digital processing circuit;

a memory circuit in communication with the digital processing circuit, the memory circuit defining a lookup table;

a digital synthesis circuit in communication with the digital processing circuit and the memory circuit, the digital synthesis circuit receiving a clock signal; and

a digital-to-analog converter (DAC) circuit;

wherein the digital processing circuit is configured to;

store phase points of a digital electrical signal waveform in the lookup table defined by the memory circuit, wherein the digital electrical signal waveform is represented by a predetermined number of phase points, and wherein the predetermined number phase points define a predetermined wave shape; and

retrieve a phase point from the lookup table at each clock cycle; and

receive a feedback signal associated with a tissue parameter; and

modify the predetermined wave shape according to the feedback signal; and

wherein the DAC circuit is configured to convert the retrieved phase point to an analog signal.

18. The generator of claim 17, comprising an amplifier coupled to the DAC circuit.

19. The generator of claim 17, wherein the digital synthesis circuit is a Direct Digital Synthesis (DDS) circuit.

20. The generator of claim 17, comprising a filter coupled to an output of the DAC circuit.