Systems and methods for reducing power consumption in an implantable medical device

• US 9,744,347 B2
• Filed: 07/01/2014
• Issued: 08/29/2017
• Est. Priority Date: 07/02/2013
• Status: Active Grant

• Current Assignee: Greatbatch Limited (Greatbatch Incorporated)
• Original Assignee: Greatbatch Limited (Greatbatch Incorporated)
• Inventors: Chen, Joey, Bradley, Kerry, Halberg, Leslie
• Primary Examiner(s): Alter, Alyssa M
• Application Number:
  US14/321,234
• Publication Number:
  US 20150012062A1
• Time in Patent Office: 1,155 Days
• Field of Search: 607 59
• CPC Class Codes: A61B 5/064 using markers A61B5/062 takes precedence
• CPC Class Codes: A61B 8/0841 for locating instruments
• CPC Class Codes: A61N 1/05 for implantation or insertion into the body, e.g. heart electrode A61N1/06 takes precedence
• CPC Class Codes: A61N 1/0551 Spinal or peripheral nerve electrodes
• CPC Class Codes: A61N 1/0553 Paddle shaped electrodes, e.g. for laminotomy
• CPC Class Codes: A61N 1/36017 with leads or electrodes penetrating the skin
• CPC Class Codes: A61N 1/36021 for treatment of pain
• CPC Class Codes: A61N 1/36071 Pain
• CPC Class Codes: A61N 1/36125 Details of circuitry or electric components
• CPC Class Codes: A61N 1/36139 with automatic adjustment
• CPC Class Codes: A61N 1/36146 specified by the stimulation parameters
• CPC Class Codes: A61N 1/36153 Voltage A61N1/3616 takes precedence
• CPC Class Codes: A61N 1/37223 Circuits for electromagnetic coupling
• CPC Class Codes: A61N 1/37235 Aspects of the external programmer
• CPC Class Codes: A61N 1/37252 Details of algorithms or data aspects of communication system, e.g. handshaking, transmitting specific data or segmenting data
• CPC Class Codes: A61N 1/3752 Details of casing-lead connections
• CPC Class Codes: A61N 1/3787 from an external energy source

Abstract

A medical device for providing a stimulation therapy includes stimulation circuitry configured to provide a plurality of electrical pulses to be delivered to a patient. The stimulation circuitry contains a microcontroller configured to generate the electrical pulses. Each electrical pulse includes a primary phase, an interphase after the primary phase, and a recovery phase after the primary phase. Consecutive electrical pulses are separated by a standby period. The microcontroller is configured to operate in an active mode during at least one of: the primary phase and the interphase. The microcontroller is configured to operate in a power-conservation mode during a substantial majority of the standby period. The microcontroller consumes substantially less power when operating in the power-conservation mode than in the active mode.

Claims

1. A medical device for providing an electrical stimulation therapy for a patient, the medical device comprising:

telemetry circuitry configured to receive programming instructions via telecommunications conducted with an electronic programmer;

stimulation circuitry configured to provide, in response to the received programming instructions, a plurality of electrical pulses to be delivered to the patient as a part, of the electrical stimulation therapy, wherein the stimulation circuitry contains a microcontroller configured to generate the electrical pulses, wherein each electrical pulse includes a primary phase, an interphase after the primary phase, and a passive recovery phase after the primary phase, and wherein consecutive electrical pulses are separated by a standby period, the microcontroller being further configured to;

operate in an active mode during at least one of;

the primary phase and the interphase;

operate in a power-conservation mode during the passive recovery phase and during a substantial majority of the standby period, the microcontroller consuming substantially less power when operating in the power-conservation mode than in the active mode; and

power supply circuitry configured to provide electrical power to the telemetry circuitry and the stimulation circuitry.

2. The medical device of claim 1, wherein the power-conservation mode is one of a plurality of available power-conservation modes in which the microcontroller can be operated.

3. The medical device of claim 1, wherein:

the microcontroller contains a microcontroller core and a direct memory access (DMA) unit that is separate from the microcontroller core and consumes substantially less power than the microcontroller core;

the microcontroller core is turned on when the microcontroller operates in the active mode and is turned off when the microcontroller operates in the power-conservation mode; and

the DMA unit remains turned on when the microcontroller operates in the power-conservation mode.

4. The medical device of claim 3, wherein:

the microcontroller contains a system clock that is running at a first frequency;

the stimulation circuitry further comprises an oscillator that is external to the microcontroller, the oscillator running at a second frequency that is substantially lower than the first frequency;

the microcontroller is driven by the system clock when operating in the active mode; and

the DMA unit is driven by the oscillator when the microcontroller operates in the power-conservation mode.

5. The medical device of claim 4, wherein when operating in the power-conservation mode, the microcontroller is configured to be woken up by an interrupt signal immediately before a subsequent electrical pulse needs to be generated, such that the microcontroller operates in the active mode after being woken up, wherein the interrupt signal is generated by a timer clocked by the oscillator.

6. The medical device of claim 1, wherein:

the power supply circuitry comprises;

an inductive charging mechanism configured to receive an inductive energy;

a charging circuit configured to convert the inductive energy into a direct current (DC) signal;

a battery charged by the charging circuit to provide a first DC voltage;

a voltage down-converter that down-converts the first DC voltage to a second DC voltage smaller than the first DC voltage, the second DC voltage being a voltage supply for at least the microcontroller; and

a voltage up-converter that up-converts the first DC voltage to a third DC voltage that is greater than the first DC voltage, the third voltage being a voltage supply for the stimulation circuitry; and

the stimulation circuitry further comprises;

a stimulation driver that amplifies the electrical pulses generated by the microcontroller; and

an array of multiplexers coupled between the stimulation driver and an external lead that includes a plurality of electrodes configured to deliver the electrical stimulation therapy to the patient.

7. The medical device of claim 6, further comprising a switch coupled between the voltage up-converter and the stimulation driver, wherein the switch is configured to disconnect the stimulation driver from the voltage up-converter during the standby period in between consecutive electrical pulses.

8. The medical device of claim 6, wherein, for each pulse:

the voltage up-converter and the array of multiplexers are enabled before the primary phase and disabled during the interphase.

9. A medical system for providing an electrical stimulation therapy for a patient, the medical system comprising:

an electronic programmer configured to generate stimulation programming instructions for an implantable pulse generator (IPG); and

the IPG, wherein the IPG comprises;

telemetry circuitry configured to receive the programming instructions via telecommunications conducted with the electronic programmer;

stimulation circuitry configured to provide, in response to the received programming instructions, a plurality of electrical pulses to be delivered to the patient as a part of the electrical stimulation therapy, wherein the stimulation circuitry contains a microcontroller configured to generate the electrical pulses, wherein each electrical pulse includes a primary phase, an interphase after the primary phase, and a passive recovery phase after the primary phase, and wherein consecutive electrical pulses are separated by a standby period, the microcontroller being further configured to;

operate in an active mode during at least one of;

the primary phase and the interphase;

operate in a power-conservation mode during the passive recovery phase and during a substantial majority of the standby period, the microcontroller consuming substantially less power when operating in the power-conservation mode than in the active mode; and

power supply circuitry configured to provide electrical power to the telemetry circuitry and the stimulation circuitry.

10. The medical system of claim 9, further comprising:

an implantable lead configured to be attached to the IPG, wherein the implantable lead contains a plurality of electrodes configured to deliver the electrical pulses generated by the IPG to a peripheral nerve of the patient.

11. The medical system of claim 9, wherein:

the power supply circuitry comprises;

an inductive charging mechanism configured to receive an inductive energy;

a charging circuit configured to convert the inductive energy into a direct current (DC) signal;

a battery charged by the charging circuit to provide a first DC voltage;

a voltage down-converter that down-converts the first DC voltage to a second DC voltage smaller than the first DC voltage, the second DC voltage being a voltage supply for at least the microcontroller; and

a voltage up-converter that up-converts the first DC voltage to a third DC voltage that is greater than the first DC voltage, the third voltage being a voltage supply for the stimulation circuitry; and

the stimulation circuitry further comprises;

a stimulation driver that amplifies the electrical pulses generated by the microcontroller; and

an array of multiplexers coupled between the stimulation driver and an external lead that includes a plurality of electrodes configured to deliver the electrical stimulation therapy to the patient.

12. The medical system of claim 11, further comprising a switch coupled between the voltage up-converter and the stimulation driver, wherein the switch is configured to disconnect the stimulation driver from the voltage up-converter during the standby period in between consecutive electrical pulses.

13. The medical system of claim 11, wherein, for each pulse:

the voltage up-converter and the array of multiplexers are enabled before the primary phase and disabled during the interphase, and the microcontroller is configured to operate in the power-conservation mode during the passive recovery phase.

14. A method of providing an electrical stimulation therapy for a patient, the method comprising:

receiving programming instructions from an electronic programmer; and

generating, via a microcontroller and in response to the received programming instructions, a plurality of electrical pulses to be delivered to the patient as a part of the electrical stimulation therapy, wherein each electrical pulse includes a primary phase, an interphase after the primary phase, and a passive recovery phase after the primary phase, wherein consecutive electrical pulses are separated by a standby period, and wherein the generating of the electrical pulses comprises;

operating the microcontroller in an active mode during at least one of;

the primary phase and the interphase;

operating the microcontroller in a power-conservation mode during the passive recovery phase and during a substantial majority of the standby period; and

wherein the microcontroller consumes substantially less power when operating in the power-conservation mode than in the active mode.

15. The method of claim 14, wherein:

the microcontroller contains a microcontroller core and a direct memory access (DMA) unit that is separate from the microcontroller core and consumes substantially less power than the microcontroller core;

the operating of the microcontroller comprises;

turning on the microcontroller core in the active mode;

turning off the microcontroller core in the power-conservation mode; and

keeping the DMA unit turned on in the power-conservation mode.

16. The method of claim 15, wherein:

the microcontroller contains a system clock that is running at a first frequency;

the microcontroller is a part of a stimulation circuitry that further comprises an oscillator that is external to the microcontroller, the oscillator running at a second frequency that is substantially lower than the first frequency;

the operating of the microcontroller comprises driving the microcontroller with the system clock in the active mode; and

driving the DMA unit with the oscillator in the power-conservation mode.

17. The method of claim 16, further comprising:

generating an interrupt signal with a timer unit that is clocked by the oscillator; and

waking up the microcontroller from the power-conservation mode via the interrupt signal immediately before a subsequent electrical pulse needs to be generated.

18. The method of claim 14, further comprising:

receiving an inductive energy;

converting the inductive energy into a direct current (DC) signal;

charging a battery with the DC signal, thereby providing a first DC voltage via the battery;

down-converting the first DC voltage to a second DC voltage smaller than the first DC voltage;

providing the second DC voltage as a voltage supply for at least the microcontroller;

up-converting the first DC voltage to a third DC voltage greater than the first DC voltage;

providing the third DC voltage as a voltage supply for a stimulation driver and an array of multiplexers coupled to the stimulation driver;

amplifying, via the stimulation driver, the electrical pulses generated by the microcontroller; and

delivering the amplified electrical pulses to the patient at least in part by configuring the array of multiplexers.

19. The method of claim 18, further comprising:

disconnecting the stimulation driver from the voltage up-converter during the standby period between consecutive electrical pulses.

20. The method of claim 18, further comprising, for each pulse:

enabling the voltage up-converter and the array of multiplexers before the primary phase;

disabling the voltage up-converter and the array of multiplexers during the interphase; and

operating the microcontroller in the power-conservation mode during the passive recovery phase.