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

• US 10,194,846 B2
• Filed: 08/25/2017
• Issued: 02/05/2019
• Est. Priority Date: 04/14/2007
• Status: Active Grant

• 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:
  US15/686,156
• Publication Number:
  US 20170354356A1
• Time in Patent Office: 529 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. A method of processing signals from an analyte sensor, comprising:

coupling a first amplifier to a second amplifier and a signal source;

determining that a first signal at an output terminal of the second amplifier exceeds a converter tolerance value; and

processing a second signal at the output terminal of the second amplifier when the first signal at the output terminal of the second amplifier exceeds the converter tolerance value.

2. The method of claim 1, wherein the first amplifier comprises a transimpedance amplifier.

3. The method of claim 2, wherein the transimpedance amplifier is coupled to an analog to digital converter, and wherein the converter tolerance value corresponds to a tolerance level of the analog to digital converter.

4. The method of claim 1, wherein the first amplifier has a higher resolution than the second amplifier.

5. The method of claim 1, wherein the first signal and the second signal are from an in vivo analyte sensor.

6. The method of claim 5, wherein the in vivo 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.

7. The method of claim 6, wherein the analyte-responsive enzyme is chemically bonded to the polymer.

8. The method of claim 6, wherein the working electrode further comprises a mediator.

9. The method of claim 5, wherein the in vivo analyte sensor comprises a plurality of electrodes including a working electrode comprising a mediator bonded to a polymer disposed on the working electrode.

10. The method of claim 9, wherein the mediator is chemically bonded to the polymer.

11. An apparatus, comprising:

a first amplifier operatively coupled to a signal source;

a second amplifier operatively coupled to the first amplifier, the second amplifier comprising an output terminal; and

a processing unit operatively coupled to one or more of the first amplifier and the second amplifier, the processing unit configured to;

determine that a first signal at the output terminal of the second amplifier exceeds a converter tolerance value; and

process a second signal at the output terminal of the second amplifier when the first signal at the output terminal of the second amplifier exceeds the converter tolerance value.

12. The apparatus of claim 11, wherein the first amplifier comprises a transimpedance amplifier.

13. The apparatus of claim 12, wherein the transimpedance amplifier is coupled to an analog to digital converter, and wherein the converter tolerance value corresponds to a tolerance level of the analog to digital converter.

14. The apparatus of claim 11, wherein the first amplifier has a higher resolution than the second amplifier.

15. The apparatus of claim 11, wherein the first signal and the second signal are sensor signals from an in vivo analyte sensor.

16. The apparatus of claim 15, wherein the in vivo 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.

17. The apparatus of claim 16, wherein the analyte-responsive enzyme is chemically bonded to the polymer.

18. The apparatus of claim 16, wherein the working electrode further comprises a mediator.

19. The apparatus of claim 15, wherein the in vivo analyte sensor comprises a plurality of electrodes including a working electrode comprising a mediator bonded to a polymer disposed on the working electrode.

20. The apparatus of claim 19, wherein the mediator is chemically bonded to the polymer.