Apparatus for tissue stimulation

• US 20060271110A1
• Filed: 05/31/2005
• Published: 11/30/2006
• Est. Priority Date: 05/31/2005
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Tyler, Larry E., Vernon, Scott D.
• Granted Patent: US 7,715,911 B2
• Time in Patent Office: Days
• US Class Current: 607/2
• CPC Class Codes: A61N 1/056 Transvascular endocardial electrode systems
• CPC Class Codes: A61N 1/3931 Protecting, e.g. back-up systems

Abstract

Delivering electrical stimulation to a body tissue by a circuit. The circuit includes a first and second terminal electrically coupled to body tissue. A sole capacitor has a first electrode and a second electrode. The first electrode is coupled to the first terminal. The second electrode is coupled to a power source through a switch.

Claims

1. An apparatus for delivering electrical stimulation to body tissue, the apparatus comprising:

first and second terminals configured to be electrically coupled to the body tissue;

a first capacitor having a first electrode coupled to the first terminal and having a second electrode;

a voltage source having an output;

a first switch for coupling the second electrode to the output of the voltage source;

a second switch configured for coupling the second electrode to a reference potential;

a third switch configured for coupling the second terminal to the reference potential; and

a current smoothing circuit coupled between the output of the voltage source and the first switch.

2. The apparatus according to claim 1, wherein the voltage source is one of a voltage converter, a charge pump and a switching regulator.

3. The apparatus according to claim 1 wherein the current smoothing circuit comprises:

a current source coupled between the output of the voltage source and the first switch; and

a second capacitor coupled between the output of the voltage source and the reference potential.

4. The apparatus according to claim 1 wherein the current smoothing circuit is a second capacitor coupled between the output of the voltage source and the reference potential.

5. The apparatus according to claim 1 wherein the current smoothing circuit comprises:

a fourth switch coupled between the output of the voltage source and the first switch; and

a second capacitor configured to be coupled between the reference potential and the common connection of the first switch and the fourth switch.

6. An apparatus for delivering electrical stimulation to body tissue, the apparatus comprising:

first and second terminals configured to be electrically coupled to the body tissue;

a sole capacitor which includes a first electrode and a second electrode, the first electrode coupled to the first terminal;

a first voltage source having an output;

a first switch for coupling the second electrode to the output of the voltage source;

a second switch configured for coupling the second electrode to a reference potential;

a third switch configured for coupling the second terminal to the reference potential;

a second voltage source having an output; and

a fourth switch coupled between the output of the second voltage source and the second electrode.

7. The apparatus according to claim 6, wherein the first voltage source is one of a voltage converter, a charge pump and a switching regulator.

8. An apparatus for delivering electrical stimulation to body tissue, the apparatus comprising:

first and second terminals configured to be electrically coupled to the body tissue;

a sole capacitor that includes a first electrode and a second electrode, the first electrode coupled to the first terminal;

a first voltage source having an output;

a first switch for coupling the second electrode to the output of the voltage source;

a second switch configured for coupling the second electrode to a reference potential;

a third switch configured for coupling the second terminal to the reference potential;

a second voltage source having an output; and

a fourth switch coupled between the output of the second voltage source and the second terminal.

9. The apparatus according to claim 8 further comprising a fifth switch coupled between the output of the second voltage source and the second electrode.

10. An apparatus for delivering electrical stimulation to body tissue, the apparatus comprising:

first and second terminals configured to be electrically coupled to the body tissue;

a sole capacitor having a first electrode and a second electrode, the first electrode coupled to the first terminal;

a voltage source having an output;

a first switch for coupling the second electrode to the output of the voltage source;

a second switch configured for coupling the second electrode to a reference potential;

a third switch configured for coupling the second terminal to the reference potential;

an adjustable impedance circuit that includes an input and an output, the input for coupling to the reference potential; and

a fourth switch coupled between the second electrode and the output of the adjustable impedance circuit.

11. An apparatus for delivering electrical stimulation to body tissue, the apparatus comprising:

first and second terminals configured to be electrically coupled to the body tissue;

a sole capacitor having a first electrode and a second electrode, the first electrode coupled to the first terminal;

a voltage source having an output;

a first switch for coupling the second electrode to the output of the voltage source;

a second switch configured for coupling the second electrode to a reference potential;

a third switch configured for coupling the second terminal to the reference potential;

an adjustable impedance circuit having an input and an output, the input coupled to the reference potential; and

a fourth switch coupled between the second terminal and the output of the adjustable impedance circuit.

12. The apparatus according to claim 11 further comprising a fifth switch coupled between the second electrode and the output of the adjustable impedance circuit.

13. An apparatus for delivering electrical stimulation to body tissue, the apparatus comprising:

first and second terminals configured to be electrically coupled to the body tissue;

a sole capacitor having a first electrode and a second electrode, the first electrode coupled to the first terminal;

a voltage source having an output;

a first switch for coupling the second electrode to the output of the voltage source;

a second switch configured for coupling the second electrode to a reference potential;

a third switch configured for coupling the second terminal to the reference potential; and

a fourth switch configured to couple the first electrode to the reference potential.

14. The apparatus according to claim 13, wherein the voltage source is one of a voltage converter, a charge pump and a switching regulator.

15. The apparatus according to claim 13 further comprising:

a current-carrying element having an output; and

a fifth switch coupled between the output of the current-carrying element and the second electrode.

16. The apparatus according to claim 13 wherein the fourth switch is a fault resistant switched conductor.

17. The apparatus according to claim 15 wherein the fourth switch is a fault resistant switched conductor.

18. An apparatus for delivering electrical stimulation to body tissue, the apparatus comprising:

first and second terminals configured to be electrically coupled to the body tissue;

a capacitor having a first electrode coupled to the first terminal and having a second electrode;

a voltage source having an output;

a first switch for coupling the second electrode to the output of the voltage source;

a second switch configured for coupling the second electrode to a first reference potential;

a first fault resistant switched conductor for coupling between the reference potential and the second terminal; and

a second fault resistant switched conductor for coupling between the reference potential and the first terminal.

19. The apparatus according to claim 18 further comprising:

a current-carrying element having an output; and

a third switch coupled between the output of the current-carrying element and the second electrode.

20. A method of changing the amplitude of a stimulation pulse applied to a patient'"'"'s body tissue from a first amplitude to a second amplitude, the method comprising:

changing the voltage stored on a sole capacitor from a first voltage to a second voltage substantially proportional to the second amplitude;

discharging the sole capacitor through the body tissue; and

changing the voltage across the capacitor to substantially the first voltage.