Power consumption reduction in medical devices by employing different supply voltages

• US 6,091,987 A
• Filed: 10/28/1998
• Issued: 07/18/2000
• Est. Priority Date: 04/29/1998
• Status: Expired due to Term

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Thompson, David L.
• Primary Examiner(s): Getzow, Scott M.
• Application Number:
  US09/181,459
• Time in Patent Office: 629 Days
• Field of Search: 607/2, 607/9, 607/5, 607/29, 607/33, 607/34
• US Class Current: 607/2
• CPC Class Codes: A61N 1/37276 characterised by means for reducing power consumption during telemetry
• CPC Class Codes: A61N 1/378 Electrical supply
• CPC Class Codes: A61N 1/3956 Implantable devices for applying electric shocks to the heart, e.g. for cardioversion
• CPC Class Codes: G05F 3/242 with compensation for device parameters, e.g. channel width modulation, threshold voltage, processing, or external variations, e.g. temperature, loading, supply voltage
• CPC Class Codes: G06F 1/3203 Power management, i.e. event-based initiation of a power-saving mode
• CPC Class Codes: G06F 1/324 by lowering clock frequency
• CPC Class Codes: G06F 1/3296 by lowering the supply or operating voltage
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management

Abstract

Power consumption in medical devices is reduced through the application of different supply voltages to analog and digital circuits, respectively. The medical device generally includes analog circuits (e.g., an atrial sense amplifier, a ventricular sense amplifier, a T-wave amplifier, bandpass filters, detection circuits, sensor amplification circuits, physiological signal amplification circuits, output circuits, a battery monitor circuit, and a power on reset circuit) and digital circuits (e.g., a processor, a controller, and a memory) with the supply voltage applied to the analog circuits being greater than that applied to the digital circuits. A source applies a first fixed supply voltage to the digital circuits of the medical device and a voltage generation circuit (e.g., a charge pump circuit) having the first fixed supply voltage applied thereto is used for generating a second fixed supply voltage to be applied to analog circuits of the medical device.

Claims

1. A medical device, comprising:

one or more analog circuits operable to perform at least one function;

one or more digital circuits operable to perform at least one function;

a power source for applying a first fixed supply voltage to the one or more digital circuits; and

a voltage generation circuit having the first fixed supply voltage supplied thereto, wherein the voltage generation circuit generates at least a second fixed supply voltage for application to the one or more analog circuits, and further wherein the second fixed supply voltage is greater than the first fixed supply voltage.

2. The device of claim 1, wherein the voltage generation circuit is a charge pump circuit for generating the second fixed supply voltage based on the first fixed supply voltage.

3. The device of claim 2, wherein the first supply voltage ranges between about 0.8 volts and about 1.5 volts.

4. The device of claim 2, wherein the second supply voltage ranges between about +/-2.0 volts and about +/-3.0 volts.

5. The device of claim 1, wherein the device further includes means for adjusting the back gate bias of at least one of the one or more digital circuits.

6. The device of claim 1, wherein the one or more digital circuits include at least one of a processor, a controller and a memory.

7. The device of claim 6, wherein the one or more analog circuits include at least one of an atrial sense amplifier, a ventricular sense amplifier, a T-wave amplifier, one or more bandpass filters, one or more detection circuits, one or more sensor amplification circuits, one or more physiological signal amplification circuits, one or more output circuits, a battery monitor circuit, and a power on reset circuit.

8. The device of claim 1, wherein the one or more digital circuits include at least one digital signal processor having the first supply voltage applied thereto receiving data representative of one or more analog signals.

9. The device of claim 1, wherein the one or more analog circuits include at least ore amplifier circuit for amplifying the one or more analog signals.

10. The device of claim 1, wherein the device further includes a level shifter to translate signals between the one or more analog circuits and the one or more digital circuits.

11. The device of claim 1, wherein the device is an hermetically sealed implantable medical device.

12. The device of claim 11, wherein the implantable medical device is selected from the group consisting of an implantable stimulator, an implantable nerve stimulator, an implantable pacemaker, an IPG, an implantable cardioverter, an implantable PCD, an implantable defibrillator, an implantable ICD and an implantable drug pump.

13. The device of claim 1, wherein at least one of the one or more analog circuits comprises circuits of a type selected from the group consisting of CMOS circuits CML circuits, SOS circuits, SOI circuits, BICMOS circuits, PMOS circuits and NMOS circuits.

14. A method for conserving power for a medical device, the method comprising the steps of:

providing one or more analog circuits of the medical device;

providing one or more digital circuits of the medical device;

applying a first fixed supply voltage to the one or more digital circuits; and

generating a second fixed supply voltage for application to the one or more analog circuits using the first fixed supply voltage, wherein the second fixed supply voltage is greater than the first fixed supply voltage.

15. The method of claim 14, wherein the step of generating the second fixed supply voltage includes the step of generating the second fixed supply voltage using a charge pump circuit.

16. The method of claim 14, wherein the first fixed supply voltage ranges between about 0.8 volts and about 1.5 volts.

17. The method of claim 14, wherein the second fixed supply voltage ranges between about +/-2.0 volts and about +/-3.0 volts.

18. The method of claim 14, wherein the method further includes the step of adjusting the back gate bias of at least one of the one or more digital circuits.

19. The method of claim 14, wherein the step of providing the one or more digital circuits includes providing at least one of a processor, a controller and a memory.

20. The method of claim 14, wherein the step of providing the one or more analog circuits includes the step of providing at least one of an atrial sense amplifier, a ventricular sense amplifier, a T-wave amplifier, one or more bandpass filters, one or more detection circuits, one or more sensor amplification circuits, one or more physiological signal amplification circuits, one or more output circuits, a battery monitor circuit, and a power on reset circuit.

21. The method of claim 14, wherein the step of providing the one or more digital circuits includes the step of providing at least one digital signal processor having the first supply voltage applied thereto for receiving data representative of one or more analog signals.

22. The method of claim 14, wherein the step of providing the one or more analog circuits includes the step of providing at least one amplifier circuit for amplifying the one or more analog signals.

23. The method of claim 14, wherein the method further includes the step of translating the voltage levels of signals being communicated between the one or ore analog circuits and the one or more digital circuits.

24. The method of claim 14, further comprising the step of providing an hermetically sealed implantable medical device.

25. The method of claim 24, wherein the implantable medical device providing step further comprises the step of providing an implantable medical device selected from the group consisting of an implantable stimulator, an implantable nerve stimulator, an implantable pacemaker, an IPG, an implantable cardioverter, an implantable PCD, an implantable defibrillator, an implantable ICD and an implantable drug pump.

26. The method of claim 14, wherein the step of providing the one or more analog circuits further comprises the step of providing circuitry of a type selected from the group consisting of CMOS circuits, CML circuits, SOS circuits, SOI circuits BICMOS circuits, PMOS circuits and NMOS circuits.