Method and apparatus for providing dynamic multi-stage signal amplification in a medical device

• US 9,743,866 B2
• Filed: 07/13/2016
• Issued: 08/29/2017
• Est. Priority Date: 04/14/2007
• Status: Expired due to Fees

• Current Assignee: Abbott Diabetes Care Incorporated (Abbott Laboratories Incorporated)
• Original Assignee: Abbott Diabetes Care Incorporated (Abbott Laboratories Incorporated)
• Inventors: Fennell, Martin J.
• Primary Examiner(s): Tweel, Jr., John A
• Application Number:
  US15/209,741
• Publication Number:
  US 20160317071A1
• Time in Patent Office: 412 Days
• Field of Search: 340511
• CPC Class Codes: A61B 2560/0209 adapted for power saving
• CPC Class Codes: A61B 2560/0252 using ambient temperature
• CPC Class Codes: A61B 2560/045 with a separable interface unit, e.g. for communication
• CPC Class Codes: A61B 5/0004 characterised by the type of physiological signal transmitted
• CPC Class Codes: A61B 5/002 Monitoring the patient using a local or closed circuit, e.g. in a room or building A61B5/0017 takes precedence
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/14546 for measuring analytes not otherwise provided for, e.g. ions, cytochromes
• CPC Class Codes: A61B 5/14865 invasive, e.g. introduced into the body by a catheter or needle or using implanted sensors
• CPC Class Codes: A61B 5/7225 Details of analog processing, e.g. isolation amplifier, gain or sensitivity adjustment, filtering, baseline or drift compensation A61B5/30, A61B5/316 take precedence; transformers for specific applications H01F38/00; amplifiers H03F
• CPC Class Codes: A61B 5/7246 using correlation, e.g. template matching or determination of similarity
• CPC Class Codes: A61B 5/7475 User input or interface means, e.g. keyboard, pointing device, joystick
• CPC Class Codes: A61M 5/1723 using feedback of body parameters, e.g. blood-sugar, pressure measurement of body parameters A61B5/00

Abstract

Methods and apparatus for providing multi-stage signal amplification in a medical telemetry system are provided.

Claims

1. An apparatus, comprising:

an analyte sensor having a portion in fluid contact with bodily fluid under a skin surface to monitor an analyte level in the bodily fluid;

a processor operatively coupled to the analyte sensor; and

a memory operatively coupled to the processor for storing instructions which, when executed by the processor, causes the processor to;

receive a first signal having a first signal resolution generated by the analyte sensor and associated with the monitored analyte level;

receive a second signal having a second signal resolution generated by the analyte sensor and associated with the monitored analyte level;

compare the received second signal to a predetermined threshold level; and

process one of the received first or the second signals based on the comparison of the received second signal to the predetermined threshold level.

2. The apparatus of claim 1, wherein the predetermined threshold level includes approximately 4,000 bits or ADC counts.

3. The apparatus of claim 1, wherein the second signal has a higher resolution compared to the first signal.

4. The apparatus of claim 1, wherein the second signal is processed based on the comparison of the received second signal to the predetermined threshold level when the received second signal does not exceed the predetermined threshold level.

5. The apparatus of claim 1, wherein the first signal is processed based on the comparison of the received second signal to the predetermined threshold level when the received second signal exceeds the predetermined threshold level.

6. The apparatus of claim 1, further comprising a high sensitivity sensor associated with the first signal and a low sensitivity sensor associated with the second signal.

7. The apparatus of claim 6, wherein the high sensitivity sensor is configured for use with a current signal level of up to approximately 150 nA, and wherein the low sensitivity sensor is configured for use with a current signal level of approximately 75 nA.

8. The apparatus of claim 1, wherein the analyte sensor comprises a plurality of electrodes including a working electrode comprising an analyte-responsive enzyme bonded to a polymer disposed on the working electrode.

9. The apparatus of claim 8, wherein the working electrode comprises a mediator crosslinked with the polymer disposed on the working electrode.

10. The apparatus of claim 1, wherein the analyte sensor comprises a plurality of electrodes including a working electrode comprising a mediator bonded to a polymer disposed on the working electrode.

11. A method, comprising:

receiving a first signal having a first signal resolution and associated with a monitored analyte level, the first signal generated by an analyte sensor having a portion in fluid contact with bodily fluid under a skin surface to monitor an analyte level in the bodily fluid;

receiving a second signal having a second signal resolution generated by the analyte sensor and associated with the monitored analyte level;

comparing the received second signal to a predetermined threshold level; and

processing one of the received first or the second signals based on the comparison of the received second signal to the predetermined threshold level.

12. The method of claim 11, wherein the predetermined threshold level includes approximately 4,000 bits or ADC counts.

13. The method of claim 11, wherein the second signal has a higher resolution compared to the first signal.

14. The method of claim 11, wherein the second signal is processed based on the comparison of the received second signal to the predetermined threshold level when the received second signal does not exceed the predetermined threshold level.

15. The method of claim 11, wherein the first signal is processed based on the comparison of the received second signal to the predetermined threshold level when the received second signal exceeds the predetermined threshold level.

16. The method of claim 11, further comprising providing a high sensitivity sensor associated with the first signal and a low sensitivity sensor associated with the second signal.

17. The method of claim 16, wherein the high sensitivity sensor is configured for use with a current signal level of up to approximately 150 nA, and wherein the low sensitivity sensor is configured for use with a current signal level of approximately 75 nA.

18. The method of claim 11, wherein the analyte sensor comprises a plurality of electrodes including a working electrode comprising an analyte-responsive enzyme bonded to a polymer disposed on the working electrode.

19. The method of claim 18, wherein the working electrode comprises a mediator crosslinked with the polymer disposed on the working electrode.

20. The method of claim 11, wherein the analyte sensor comprises a plurality of electrodes including a working electrode comprising a mediator bonded to a polymer disposed on the working electrode.