Implanted Driver with Resistive Charge Balancing

• US 20090157150A1
• Filed: 11/26/2008
• Published: 06/18/2009
• Est. Priority Date: 11/26/2007
• Status: Abandoned Application

• Current Assignee: MicroTransponder Inc., Board of Regents of the University of Texas System (University of Texas System)
• Original Assignee: MicroTransponder Inc., Board of Regents of the University of Texas System (University of Texas System)
• Inventors: Cauller, Lawrence
• Application Number:
  US12/323,969
• Publication Number:
  US 20090157150A1
• Time in Patent Office: Days
• US Class Current: 607/72
• CPC Class Codes: A61B 2560/0219 of externally powered implanted units
• CPC Class Codes: A61B 2562/028 Microscale sensors, e.g. electromechanical sensors [MEMS]
• CPC Class Codes: A61B 5/6849 in combination with a needle set
• CPC Class Codes: A61N 1/36071 Pain
• CPC Class Codes: A61N 1/36125 Details of circuitry or electric components
• CPC Class Codes: A61N 1/37205 Microstimulators, e.g. implantable through a cannula
• CPC Class Codes: A61N 1/37229 Shape or location of the implanted or external antenna
• CPC Class Codes: A61N 1/3756 Casings with electrodes thereon, e.g. leadless stimulators

Abstract

A transponder includes a stimulus driver configured to discharge an electrical stimulus when a trigger signal is received. A first conducting electrode is coupled to the stimulus driver and conducts the electrical stimulus discharged by the stimulus driver. A second conducting electrode is coupled to the stimulus driver and conducts the electrical stimulus conducted by the first conducting electrode. A depolarization resistance connects the first conducting electrode to the second conducting electrode in response to the trigger signal.

Claims

1. A method of providing stimulation pulses to tissue, comprising the steps of:

providing stimulation pulses to said tissue; and

reducing polarization in said tissue.

5. The method of claim 1, wherein reducing polarization includes a depolarization switch connected between two electrodes.

6. The method of claim 5, wherein the depolarization switch comprises at least one bipolar switch.

7. The method of claim 5, further comprising the step of:

shorting the electrodes at least once each cycle; and

timing the depolarization switch to permit the stimulation pulses to be substantially discharged before closing the depolarization switch.

8. The method of claim 5, further comprising the step of:

shorting the electrodes at least once each cycle; and

timing the depolarization switch to open before a subsequent stimulation pulse arrives.

9. The method of claim 1, further comprising the step of:

connecting a high-value clamping resistor across a set of output terminals, wherein the resistor impedance is higher than a differential impedance at full pulse power and provides a direct current path to discharge the polarization into the terminals.

10. The method of claim 1, further comprising the step of:

reducing polarization of said tissue by dampening said pulses with a resistive path, in an implanted electronic unit, which has a real resistive component which is larger than the magnitude of differential impedance of the tissue at full amplitude of said pulses, and smaller than the magnitude of differential impedance of the tissue when the amplitude of said pulses is at 10% of its maximum.

11. The method of claim 1, further comprising the steps of:

providing the stimulation pulses to surrounding tissue over a voltage range in which said tissue has nonlinear impedance.

2. A wireless stimulation method comprising:

wirelessly powering an implanted electronic unit;

using said implanted unit to provide stimulation pulses to surrounding tissue, over a voltage range in which said tissue has nonlinear impedance; and

reducing polarization of said tissue by dampening said pulses with a resistive path, in the implanted electronic unit, which has a real resistance component which is larger than the magnitude of differential impedance of the tissue at the full amplitude of said pulses, and smaller than the magnitude of differential impedance of the tissue when the amplitude of said pulses is at 10% of its maximum.

12. The method of claim 2, wherein reducing polarization includes a depolarization switch connected between two electrodes.

13. The method of claim 2, further comprising the step of:

shorting the electrodes at least once each cycle; and

timing the shorting to permit the stimulation pulses to be substantially discharged before closing the resistive path.

14. The method of claim 2, further comprising the step of:

shorting the electrodes at least once each cycle; and

timing the shorting to open the path before a subsequent stimulation pulse arrives.

15. The method of claim 2, further comprising the step of:

connecting a high-value clamping resistor across a set of output terminals, wherein the resistor impedance is higher than a differential impedance at full pulse power and provides a direct current path to discharge the polarization into the terminals.

16. The method of claim 2, wherein the resistive path comprises at least one bipolar switch.

3. (canceled)

4. A stimulation driver to provide discontinuous stimulation pulses to cellular matter comprising:

biocompatible electrodes receiving discontinuous stimulation pulses;

a resistive connection between said biocompatible electrodes and having a time constant such that polarization of the cellular matter is reduced between said discontinuous stimulation pulses.

17. The driver of claim 4, wherein the resistive connection comprises a depolarization switch timed to permit the stimulation pulses to be substantially discharged before closing the depolarization switch.

18. The driver of claim 4, wherein the resistive connection comprises a depolarization switch timed to open before a subsequent stimulation pulse arrives.

19. The driver of claim 4, further comprising a high-value clamping resistor connected across a set of output terminals, wherein the resistor impedance is higher than a differential impedance at full pulse power and provides a direct current path to discharge the polarization into the terminals.

20. The driver of claim 4, further comprising the resistive connection dampening said pulses to reduce polarization of said tissue in an implanted electronic unit, which has a real resistive component which is larger than the magnitude of differential impedance of the tissue at full amplitude of said pulses, and smaller than the magnitude of differential impedance of the tissue when the amplitude of said pulses is at 10% of its maximum.