Device and circuitry for controlling delivery of stimulation signals

1. A device for controlling delivery of stimulation signals, comprising:

a stimulation delivery circuit;

a monitoring component to monitor the waveform of the voltage supplied in at least one current-driven charge pulse via the stimulation delivery circuit;

a stimulation control component to control the waveform of the voltage supplied in at least one subsequent voltage-driven charge pulse based on the charge of the at least one current-driven charge pulse delivered by the stimulation delivery circuit; and

a model generation component to generate an impedance model of stimulation electrodes in the stimulation delivery circuit, wherein the stimulation control component is configured to control the stimulation delivery circuit to deliver charge according to the impedance model,

wherein the impedance model is a RC circuit impedance model.

2. The device of claim 1 , wherein the model generation component is configured to generate the impedance model based on measured voltage and controlled current delivery via the stimulation delivery circuit during the at least one charge pulse.

3. The device of claim 1 , wherein the model generation component is configured to periodically regenerate the impedance model based on a selected subsequently delivered charge pulse.

4. The device of claim 1 , wherein the model generation component is configured to generate an impedance model in respect of each of a plurality of sets of electrodes, where each set of electrodes includes one or more electrodes.

5. The device of claim 1 , further comprising a processor, wherein the monitoring component and stimulation control component comprise code modules accessible to the processor and executable by the processor, and wherein the processor is configured to control delivery of charge by the stimulation delivery circuit.

6. A device for controlling delivery of stimulation signals, comprising:

a stimulation delivery circuit;

a monitoring component to monitor the waveform of the voltage supplied in at least one current-driven charge pulse via the stimulation delivery circuit;

a stimulation control component to control the waveform of the voltage supplied in at least one subsequent voltage-driven charge pulse based on the charge of the at least one current-driven charge pulse delivered by the stimulation delivery circuit; and

a model generation component to generate an impedance model of stimulation electrodes in the stimulation delivery circuit, wherein the stimulation control component is configured to control the stimulation delivery circuit to deliver charge according to the impedance model,

wherein the model generation component is configured to use an adjustment model to adjust the pulse width or quantum of charge to be delivered according to the impedance model.

7. The device of claim 6 , wherein the model generation component is configured to generate the impedance model based on measured voltage and controlled current delivery via the stimulation delivery circuit during the at least one charge pulse.

8. A device for controlling delivery of stimulation signals, comprising:

a stimulation delivery circuit;

a monitoring component to monitor the waveform of the voltage supplied in at least one current-driven charge pulse via the stimulation delivery circuit;

a stimulation control component to control the waveform of the voltage supplied in at least one subsequent voltage-driven charge pulse based on the charge of the at least one current-driven charge pulse delivered by the stimulation delivery circuit;

a model generation component to generate an impedance model of stimulation electrodes in the stimulation delivery circuit, wherein the stimulation control component is configured to control the stimulation delivery circuit to deliver charge according to the impedance model; and

a processor, wherein the model generation component comprises a code module accessible to the processor and executable by the processor.

9. The device of claim 8 , wherein the monitoring component and stimulation control component comprise code modules accessible to the processor and executable by the processor, and wherein the processor is configured to control delivery of charge by the stimulation delivery circuit.

10. The device of claim 8 , wherein the model generation component is configured to periodically regenerate the impedance model based on a selected subsequently delivered charge pulse.

11. The device of claim 8 , wherein the model generation component is configured to generate the impedance model based on measured voltage and controlled current delivery via the stimulation delivery circuit during the at least one charge pulse.

12. The device of claim 8 , wherein the device is configured for use as part of a prosthesis.

13. The device of claim 12 , wherein the prosthesis is a sensory prosthesis.

14. The device of claim 12 , wherein the prosthesis is an implantable or partially implantable prosthesis.

15. The device of claim 8 , wherein the device is an implantable or partially implantable brain stimulation device.

16. The device of claim 8 , wherein the device is an implantable or partially implantable stimulation device.

17. A prosthesis comprising the device of claim 8 .

18. The device of claim 8 , wherein the model generation component is configured to generate an impedance model in respect of each of a plurality of sets of electrodes, where each set of electrodes includes one or more electrodes.

19. A device for controlling delivery of stimulation signals, comprising:

a stimulation delivery circuit;

a control component to control delivery of a waveform of at least one initial charge pulse via the stimulation delivery circuit based on a first control parameter and to control delivery of a waveform of at least one subsequent charge pulse via the stimulation delivery circuit based on a second control parameter; and

an adjustment component to modify controlled delivery of a quantum of charge delivered by the at least one subsequent charge pulse based on an adjustment model;

wherein the at least one initial charge pulse is one of current-driven and voltage-driven, and wherein if the at least one initial charge pulse is current-driven, then the at least one subsequent charge pulse is voltage-driven, and if the at least one initial charge pulse is voltage-driven, then the at least one subsequent charge pulse is current-driven,

wherein the adjustment component modifies delivery of the at least one subsequent charge pulse by increasing or decreasing at least one pulse width of the at least one subsequent charge pulse.

20. A device for controlling delivery of stimulation signals, comprising:

a stimulation delivery circuit;

a control component to control delivery of at least one charge pulse via the stimulation delivery circuit based on an impedance model of a plurality of stimulation electrodes; and

an adjustment component to modify controlled delivery of the at least one charge pulse based on an adjustment model;

wherein the adjustment component modifies delivery of the at least one charge pulse by increasing or decreasing at least one pulse width of the at least one charge pulse.