Analyte meter test strip detection

Patent metadata

Field	Value
Publication number	US-9442089-B2
Application number	US-201314138820-A
Country	US
Kind code	B2
Filing date	Dec 23, 2013
Priority date	Dec 23, 2013
Publication date	Sep 13, 2016
Grant date	Sep 13, 2016

Abstract

An analyte meter having a test strip port is configured to detect an inserted test strip using an unpowered grounded op amp while the analyte meter is in sleep mode. After a test strip is inserted and the meter is activated, the op amp is powered and provides the sample current for measuring an analyte concentration in the sample.

First claim

What is claimed is:

1. An analyte meter comprising:
a strip port connector configured to receive an electrochemical based analytical test strip inserted therein;
a front end circuit electrically connected to the analytical test strip, the front end circuit comprising an op amp for providing a signal at its output node corresponding to an analyte concentration of a sample applied to the analytical test strip while the op amp is powered; and
a strip detect signal line connected to a voltage supply and to a ground, wherein the ground connection is provided through the inserted test strip and through the output node of the op amp while the op amp is in an unpowered state.

2. The analyte meter of claim 1 , wherein the ground connection through the output node of the op amp comprises a feedback circuit in parallel with the op amp.

3. The analyte meter of claim 2 , wherein the feedback circuit comprises a capacitor and a resistor connected in parallel.

4. The analyte meter of claim 3 , wherein the analyte meter is configured with an active mode and a sleep mode, and wherein the unpowered state of the op amp corresponds to the sleep mode of the analyte meter.

5. The analyte meter of claim 3 , wherein the op amp is powered by the analyte meter in response to the analyte meter sensing the ground voltage on the strip detect line.

6. The analyte meter of claim 1 , wherein the voltage supply causes the strip detect signal line to be at a digital high voltage level when the test strip is not inserted in the strip port connector.

7. The analyte meter of claim 1 , wherein the analyte meter is programmed to periodically sense the voltage on the strip detect signal line.

8. An analyte meter comprising:
a strip port connector for receiving a test strip inserted therein and for measuring an analyte level of a sample in a sample chamber of the test strip;
a working electrode circuit connectable to ground when the test strip is inserted in the strip port connector and connectable to the sample in the inserted test strip for generating a signal corresponding to the analyte level in the sample, the working electrode circuit comprising an op amp; and
a microcontroller connected to an output of the op amp for receiving therefrom the signal corresponding to the analyte level in the sample and for connecting the output of the op amp to ground for generating a strip detect signal when the test strip is inserted in the strip port connector.

9. The analyte meter of claim 8 , further comprising a strip detect signal line that is connected to the working electrode circuit when the test strip is inserted in the strip port connector.

10. The analyte meter of claim 9 , wherein a ground voltage level comprises the strip detect signal, and wherein the strip detect signal is transmitted over the strip detect signal line to the microcontroller.

11. The analyte meter of claim 10 , further comprising a sleep state wherein the op amp is unpowered and wherein the test strip is not inserted in the strip port connector.

12. The analyte meter of claim 11 , wherein the strip detect signal line is at a logical 1 voltage level during the sleep state.

13. The analyte meter of claim 12 , wherein the working electrode circuit further comprises a feedback circuit connected to the op amp, the feedback circuit comprising a capacitor and resistor connected in parallel.

14. The analyte meter of claim 11 , wherein the microcontroller switches the analyte meter from the sleep state to an active state and powers the op amp in response to receiving the strip detect signal.

15. The analyte meter of claim 14 , wherein the microcontroller disconnects the output of the op amp from the ground in response to receiving the strip detect signal.

16. The analyte meter of claim 13 , wherein the working electrode circuit is connected to an inverting input of the op amp and a reference voltage source is connected to the non-inverting input of the op amp.

17. A method of operating an analyte meter having a strip port connector configured for receiving a test strip inserted therein, and a measurement circuit for measuring an analyte level of a sample in the inserted test strip, the method comprising:
maintaining the analyte meter in a low power inactive mode in the absence of a strip detect signal being received;
periodically monitoring a strip detect signal line for the strip detect signal, including connecting the strip detect signal line to a voltage source;
configuring the strip detect signal line and the measurement circuit such that the inserted test strip couples the strip detect signal line to a grounded output of an op amp to generate the strip detect signal; and
switching the analyte meter to an active mode from the low power inactive mode in response to receiving the strip detect signal.

18. The method of claim 17 , wherein the step of maintaining the analyte meter in a low power inactive mode further comprises unpowering the op amp and connecting an output of the op amp to ground.

19. The method of claim 18 , wherein the step of switching the analyte meter to the active mode includes powering the op amp and disconnecting its output from the ground.

20. The method of claim 19 , further comprising measuring the analyte level of the sample in the inserted test strip including measuring a current level at the output of the powered op amp.

Assignees

• Lifescan Scotland Ltd

Inventors

• Massari Rossano
• Pozzi Emanuele
• Lloyd Tim
• Elder David

Classifications

• G01N27/307 Primary

  Disposable laminated or multilayered electrodes (G01N27/3272 takes precedence) · CPC title

• G01N33/48785 Primary

  Electrical and electronic details of measuring devices for physical analysis of liquid biological material not specific to a particular test method, e.g. user interface or power supply · CPC title

• G01N33/48

  Biological material, e.g. blood, urine (G01N33/02, G01N33/26, G01N33/44, G01N33/46 take precedence); Haemocytometers (counting blood corpuscules distributed over a surface by scanning the surface G06M11/02) · CPC title

• G01N27/26 Primary

  by investigating electrochemical variables; by using electrolysis or electrophoresis · CPC title