WO2001062335B1

WO2001062335B1 - Implantable medical device incorporating adiabatic clock-powered logic

Info

Publication number: WO2001062335B1
Application number: PCT/US2001/005778
Authority: WO
Inventors: Carl A Schu; Daniel R Greeninger; David L Thompson
Original assignee: Medtronic Inc
Priority date: 2000-02-25
Filing date: 2001-02-23
Publication date: 2002-04-18
Also published as: DE60110385D1; DE60110385T2; WO2001062335A2; WO2001062335A3; EP1259289B1; US6415181B1; EP1259289A2

Abstract

Improved operating system architecture for an implantable medical device incorporating adiabatic clock-powered logic alone or in conjunction with conventional clocked logic or self-timed logic for reducing power consumption and increasing and improving processing capabilities is disclosed. The adiabatic clock-powered logic is employed to implement digital signal processors (DSPs) including analog to digital (ADC) signal converters, a state machine or the components of microprocessor cores, e.g., the CPU, arithmetic logic units (ALU), on-chip RAM and ROM and data and control buses, and other logic units, e.g., additional RAM and ROM, a direct memory address (DMA) controller, a block mover/reader, a cyclic redundancy code (CRC) calculator, and certain uplink and downlink telemetry signal processing stages. The adiabatic clocked CMOS logic is incorporated into the same IC or ICs with clocked CMOS logic and provides manufacturing economies.

Claims

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AMENDED CLAIMS

[received by the International Bureau on 19 November 2001 (19.1 1.01); original claims 1-33 replaced by amended claims 1-16 (4 pages)]

1. An implantable medical device (100) for at least one of delivering a therapy to a patient's body and monitoring a physiologic condition of a patient, said device having a battery (136) to provide battery energy; a control and timing circuit (102) powered by the battery; a physiological input sensing and signal processing circuit (108) for sensing a signal indicative of a physiologic condition of the patient and providing a sensed physiologic event signal; and a system clock (122) providing clock signals through a clock tree; said implantable medical device characterized in that: at least one adiabatic clock-powered logic circuit (150) is coupled to said clock tree and is responsive to said clock signals to perform a defined circuit function employing the energy of said clock signal and in timed synchrony with the clock. 21 The implantable medical device of claim 1 , further characterized in that: said physiological input sensing and signal processing circuit (108) includes at least one self-timed logic circuit (142) that operates independent of said system clock to provide the sensed physiologic event signal, whereby the clock tree is rninimized and clock energy is conserved.

3. The implantable medical device of claim 1, further characterized in that: said system clock provides adiabatic clock signals. 4.: The implantable medical device of claim 2, further characterized in that: said self-timed logic circuit comprises a digital signal processor, said signal processor having a plurality of self-timed logic elements formed into a chain that receives the sensed physiologic condition signal at an input, processes the sensed physiologic

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condition signal, and provides the processed physiologic event signal at an output after a self-timed logic propagation delay.

5. The implantable medical device of claim 4, wherein the signal processor provides analog-to-digital conversion of the sensed physiologic condition signal, forms a digitized physiologic condition signal, and processes the digitized physiologic condition signal.

6. The implantable medical device of claim 1, wherein: said adiabatic clock-powered logic circuit comprises at least one timer that times out time periods as multiples of the clock signal time period in response to a sensed physiologic event signal; and further comprising: means responsive to time-out of a time period by said timer for perfomiing a first device operation; and means responsive to a sensed physiologic event signal occurring during time-out of a time period by said timer for performing a second device operation.

7. The implantable medical device of claim 4, further characterized in that: the signal processor (142) comprises a digital signal processor that provides analog-to-digital conversion of the sensed physiologic event . signal, forms a digitized physiologic event signal, processes the digitized physiologic event signal with reference to predeteπriined ώsαimination criteria, deteπnines the presence or absence of a predefined characteristic of the sensed physiologic event signal, and provides a sensed event signal upon determination of the predefined characteristic.

8. The implantable medical device of claim 2. further characterized in that said self- timed logic circuit further comprises:

a microprocessor, a timing and control bus, and RAM/ROM memory to store data and instruction sets implementing device operation algorithms.

9. The implantable medical device of claim 1 wherein the timing and control circuit (102) provides iming and control functions to implement a cardiac pacemaker.

10. The implantable medical device of claim 8 wherein said self-timed logic circuit includes a memory having a plurality of memory locations; and means for triggering storage of a sensed physiologic event signal in the plurality of emory locations.

11. The implantable medical device of claim 2, further characterized in that: said self-timed logic further comprises a microprocessor, a timing and control bus, and RAM/ROM memory that stores data and operating instruction sets of device operation algorithms, the microprocessor operating pursuant to the stored data and operating instruction sets to establish timed out time periods and perform pacing pulse delivery and to adjust sensing criteria for sensing cardiac events.

12. An implantable medical monitor for periodically monitoring a physiologic condition of a patient having a physiologic sensor (108) generating a sensed physiologic signal in response to a trigger signal; a timing and control circuit (102); a system clock (122) providing clock signals through a clock tree; a signal processor (142) to process sensed physiologic signals .generated by the physiologic sensor; and a memory (144) to store processed sensed physiologic signal data; said implantable medical monitor characterized in that: an adiabatic clock-powered logic circuit (150) is coupled to said clock tree to time-out a monitoring interval and generate a trigger signal upon time-out that

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activates the physiologic sensor (108) to generate a sensed physiologic signal.

13. The implantable medical monitor of claim 12 further characterized in that: said signal processor comprises a plurality of self-timed logic elements formed into a chain that receives the sensed physiologic signal at an input thereof, processes the signal, and provides the processed physiologic signal at an output after a self-timed logic propagation delay.

14. The implantable medical monitor of claim 12 wherein the physiologic sensor includes cardiac sensing electrodes.

15. The implantable medical monitor of claim 12 wherein ihe physiologic sensor senses the level of physical activity of a patient. '

16. The implantable medical monitor of claim 12 wherein the physiologic sensor senses a condition of the blood including blood pressure, blood temperature, blood gas concentration, and blood pH.

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The amendments provided by new claims 1-16 do not have any impact on the description or the drawings.

The difference between the new claims 1-16 being presented and the original claims is that the subject matter of the invention is set forth in a more concise fashion and emphasizes the feature of medical device having at least onei adiabatic clock-powered logic circuit operating in response to adiabatic clock signals ito process a physiologic signal and provide a processed physiologic signal at an output in timed relation to the adiabatic clock signal, whereby power consumption is reduced.

The new claims 1-16 distinguish from the subject matter disclosed in the references cited in the International Search Report in that none of the citations discloses an implantable medical device using adiabatic clock-powered logic circuit operating in response to adiabatic clock signals to implement the functions of therapy delivery or monitoring.

Although adiabatic logic gates have been proposed for use in battery-powered products (see, e. , EP 0 626 757 at column 2, line 42), there is no suggestion that the functions of implantable medical devices can be implemented using adiabatic clock- powered logic circuitry. Accordingly, the new claims 1-16 clearly are novel and present