Active electrode state control system with current compensation to reduce residual DC/LF voltage
A body stimulating device operatively adapted to provide electrical stimuli within a body, the device including stimulating electrodes, stimulus generator, and electrode voltage sensors, said electrode voltage sensors operatively measuring the DC/LF voltage of the electrodes, wherein if the sensors determine that the electrode voltage for an electrode is outside a predetermined range, then a compensating current is applied to that electrode, so as to reduce the voltage.
1. A method of controlling DC/LF voltage in a body stimulating electrode system, the method comprising:
measuring the residual DC/LF voltage between each stimulating electrode and body tissue;
if a residual voltage is outside a predetermined range, then applying a compensating current of opposite polarity to reduce the residual voltage.
2. The method according to claim 1 , wherein the residual voltage is measured relative to a reference electrode operatively in electrical contact with body tissue, which does not carry a current.
3. The method according to claim 1 , wherein the measured voltage is filtered so as to suppress stimulation artifacts.
4. The method according claim 1 , wherein a feedback control system is provided and associated with each stimulating electrode.
5. The method according to claim 1 , wherein a central control arrangement is provided to control the compensating currents.
6. The method according to claim 5 , wherein the central control arrangement also controls the stimulating currents.
7. A method of controlling DC/LF voltage in a body stimulating electrode system, the method comprising:
measuring the residual DC/LF voltage associated with each stimulating electrode;
if a residual voltage is outside a predetermined range, then applying a compensating current of opposite polarity to reduce the residual voltage;
wherein the residual voltage is measured relative to a reference electrode operatively in electrical contact with body tissue, which does not carry a current;
wherein the reference electrode has a relatively large surface area as compared to a surface area of each stimulating electrode.
8. The method according to claim 7 , wherein the surface area of the reference electrode is at least about four times greater than the surface area of each stimulating electrode.
9. A body stimulating device, operatively adapted to provide electrical stimuli with in a body, the device including:
stimulating electrodes,
a stimulus generator, and
electrode voltage sensors,
said electrode voltage sensors operatively measuring the DC/LF voltage the electrodes and body tissue,
wherein if the sensors determine that the electrode voltage for an electrode is outside a predetermined range, then a compensating current is applied to that electrode, so as to reduce the voltage.
10. The device according to claim 9 , wherein each voltage sensor operates between a respective stimulating electrode and a reference electrode, operatively in electrical contact with body tissue, which does not carry a current.
11. The device according to claim 9 , wherein the electrode voltage measured by each sensor is filtered so as to suppress stimulation artifacts.
12. The device according to claim 9 , wherein a feedback control system is provided associated with each stimulating electrode.
13. The device according to claim 9 , wherein a central processor is provided to control the compensating currents.
14. The device according to claim 13 , wherein the central processor also controls the stimulus generator.
15. A body stimulating device, operatively adapted to provide electrical stimuli with in a body, the device including:
stimulating electrodes,
a stimulus generator, and
electrode voltage sensors,
said electrode voltage sensors operatively measuring the DC/LF voltage the electrodes and body tissue,
wherein if the sensors determine that the electrode voltage for an electrode is outside a predetermined ran e then a compensation current is applied to that electrode so as to reduce the voltage;
wherein each voltage sensor operates between a respective stimulating electrode and a reference electrode, operatively in electrical contact with body tissue, which does not carry a current; and
wherein the reference electrode has a relatively large surface area as compared to a surface area of each stimulating electrode.
16. The device according to claim 15 , wherein the surface area of the reference electrode is at least about four times greater than the surface area of each stimulating electrode.