Neurostimulator with reduced size

1. An implantable medical device (IMD) for implantation in the body of a patient, comprising:

a sealed housing having a total volume of less than 14.5 cc;

a power supply contained within said sealed housing for generating a power signal, said power supply comprising a charge capacity of at least about 100 milliAmpHours;

a controller to control an operation of said power supply and to provide an electrical neurostimulation signal for stimulating neural tissue of the patient,

a multi-function integrated circuit for generating an electrical neurostimulation signal from said power signal, said multi-function integrated circuit comprising a boost converter to provide a controlled current for generating said electrical neurostimulation signal and a stimulus current regulator to perform a regulation function of said current, and

a boost coil circuit for interfacing with said boost converter to provide said stimulation current.

2. The implantable medical device of claim 1 , wherein said sealed housing comprises a total volume of less than about 10 cc.

3. The implantable medical device of claim 1 , wherein said sealed housing comprises a total volume of less than about 8 cc.

4. The implantable medical device of claim 1 , wherein said power source comprises a charge capacity of at least about 500 milliAmpHours.

5. The implantable medical device of claim 1 , wherein said power source comprises a charge capacity of at least about 1000 milliAmpHours.

6. The implantable medical device of claim 1 , wherein said neural tissue is at least one of a right vagus nerve and a left vagus nerve.

7. The implantable medical device of claim 1 , wherein said implantable medical device may be used to treat at least one of a neuromuscular, neuropsychiatric, cognitive, autonomic, and a sensory disorder.

8. The implantable medical device of claim 1 wherein implantable medical device may be used to treat a disorder from a group consisting of epilepsy, depression, and bulimia.

9. The implantable medical device of claim 1 , wherein the implantable medical device comprises a stimulating current consumption when said implantable medical device provides said electrical neurostimulation signal, and a non-stimulating current consumption, and said implantable medical device is characterized by a non-stimulating current consumption of less than about 5 micro-Amps.

10. The implantable medical device of claim 9 , wherein the current consumption of said implantable medical device is characterized by a non-stimulating current consumption of less than about 1 micro-Amp.

11. The implantable medical device of claim 1 , wherein said controller comprises a stimulation unit, said stimulation unit comprising the multi-function integrated circuit.

12. The implantable medical device of claim 1 , wherein said stimulus current regulator provides a controlled current neurostimulation signal.

13. The implantable medical device of claim 1 , wherein said boost converter and said stimulus current regulator provide for an efficiency in converting energy from said power supply to stimulation energy, from a range of about 70 percent to about 95 percent.

14. The implantable medical device of claim 11 , wherein said multi-function integrated circuit comprises a switching network operatively coupled to said stimulus current regulator and operating to switch said stimulating current to at least one stimulation electrode.

15. The implantable medical device of claim 11 , wherein said multi-function integrated circuit further comprises:

a sensor electrode switching network to switch data from at least one sensor electrode; and

at least one sense amplifier to condition said data from said sensor electrode.

16. The implantable medical device of claim 11 , wherein said multi-function integrated circuit further comprises:

a supply voltage regulator for regulating a voltage of the power signal from said power supply unit; and

an internal reference for providing a voltage reference signal for comparison selected from the group consisting a voltage regulator and a current regulator.

17. The implantable medical device of claim 11 , wherein said multi-function integrated circuit further comprises:

a telemetry transceiver for providing receiving and sending data from a source external to said multi-function integrated chip; and

a reset detector to receive a reset signal and cause a reset of at least a portion of said implantable medical device.

18. The implantable medical device of claim 1 , further comprising a reset detector to receive a reset signal and cause a reset of at least a portion of said implantable medical device.

19. The implantable medical device of claim 1 , further comprising a magnet detector to determine the presence of a magnet proximate to said implantable medical device.

20. The implantable medical device of claim 1 , wherein said controller comprises a processor being implemented in an interrupt driven architecture.

21. The implantable medical device of claim 20 , wherein said processor requires an operating current of less than about 1 micro-Amp when not executing instructions.

22. An implantable medical device (IMD) comprising a power supply for generating a power signal, a multi-function integrated circuit for generating an electrical neurostimulation signal from said power signal, said multi-function integrated circuit comprising a boost converter to provide a controlled current for generating said electrical neurostimulation signal and a stimulus current regulator to perform a regulation function of said current, the IMD further comprising a boost coil circuit for interfacing with said boost converter to provide said stimulation current.

23. The implantable medical device of claim 22 , wherein said multi-function integrated circuit further comprises a switching network operatively coupled to said stimulus current regulator and operating to switch said current to at least one stimulation electrode.

24. The implantable medical device of claim 22 , wherein said multi-function integrated circuit further comprises:

a sensor electrode switching network to switch data from at least one sensor electrode; and

at least one sense amplifier to condition said data from said sensor electrode.

25. The implantable medical device of claim 22 , wherein said multi-function integrated circuit further comprises:

a telemetry transceiver for receiving and sending data from a source external to said implantable medical device and a reset detector to receive a reset signal and cause a reset of at least a portion of said implantable medical device.

26. The implantable medical device of claim 22 , further comprising:

a sealed housing having a total volume of less than about 14.5 cc;

a power supply contained within said sealed housing, said power supply comprising a charge capacity of greater than about 100 milliAmpHours; and

a controller to control an operation of said power supply and to provide said electrical neurostimulation signal for stimulating a neural tissue of a patient.

27. An implantable medical device (IMD) comprising a power supply for generating a power signal, a multi-function integrated circuit for generating an electrical neurostimulation signal, said multi-function integrated circuit comprising:

a boost converter to provide a controlled current for generating said electrical neurostimulation signal;

a stimulus current regulator to regulate said current;

a switching network operatively coupled to said stimulus current regulator and operating to switch said current to at least one stimulation electrode;

a supply voltage regulator for regulating a voltage of said power signal from said power supply unit;

an internal voltage reference for providing a reference voltage signal for comparison;

a telemetry transceiver for receiving and sending data from a source external to said implantable medical device; and

a reset detector to receive a reset signal and cause a reset of at least a portion of said implantable medical device,

the IMD further comprising a boost coil circuit for interfacing with said boost converter to provide said stimulation current.

28. The implantable medical device of claim 27 , further comprising:

a sensor electrode switching network to switch data from at least one sensor electrode;

at least one sense amplifier to condition said data from said sensor electrode; and

a register for registering data.

29. The implantable medical device of claim 27 , further comprising ceramic capacitors.

30. The implantable medical device of claim 27 , wherein said multi-function integrated circuit is coupled to a printed circuit board in a sealed housing of a total volume of less than about 14.5 cc.

31. A method for performing neurostimulation using an implantable medical device (IMD), comprising:

providing a controller to perform a function relating to said neurostimulation;

providing a multi-function integrated circuit comprising a boost converter to provide a controlled current to perform a function relating to said neurostimulation;

providing a boost coil circuit for interfacing with said boost converter to provide said stimulation current;

placing said controller in a power save mode, said power save mode comprising said multi-function integrated circuit performing at least one function relating to said neurostimulation during at least a portion of a time period during said power save mode;

receiving an interrupt relating to performing a task; and

exiting said power save operation mode to perform said task in response to said interrupt.

32. The method of claim 29 , further comprising:

determining whether the performance of said task is substantially complete; and

entering said power save mode in response to a determination that said performance of said task is substantially complete.