US5405511A
Expired / Lapsed
US
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Biosensing meter with ambient temperature estimation method and system
Assignee: Roche Diabetes Care Inc
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Filing: 1993-06-08
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Granted: 1995-04-11
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Expires: 2013-06-08
Abstract
Abstract A biosensing meter is provided that determines a value of an analyte in a biological sample. The meter employs an algorithm for determining the analyte value, which value is dependent upon ambient temperature about the biological sample when it is present in a reaction zone. The biosensing meter includes a processor and a temperature sensor. The temperature sensor is positioned within the meter's structure and thereby exhibits a delayed response to changes in the ambient temperature. The meter performs a temperature estimation method to overcome the delayed temperature response. The method commences by the meter repetitively and periodically acquiring temperature readings from the temperature sensor when the biosensing meter is both in an on state and in an off state. When the meter is in the on state, the algorithm estimates the ambient temperature by employing at least two most recent temperature readings and extrapolating therefrom to achieve an ambient temperature estimate. Temperature readings are acquired by the meter at first intervals when the meter is in the off state and at second, shorter intervals when the meter is in the on state, the temperature extrapolations only occurring when the meter is in the on state.
Inventors
- 👤 Bradley E. White
- 👤 Michael L. Brown
- 👤 Paul G. Ritchie
- 👤 Vladimir Svetnik
- 👤 Robert A. Parks
- 👤 Stefan Weinert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 15:50
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/26; G01N27/28; G01N27/30; G01N27/327; G01N27/3271; G01N27/3274; G01K; G01K7/00; G01K7/42
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
144 words
A temperature estimation method for use in a biosensing meter that determines a value of an analyte in a biological sample, a determined analyte value dependent upon an ambient temperature about said biological sample, said biosensing meter including a processor and a temperature sensor, said temperature sensor positioned within said meter and thereby exhibiting a delayed response to changes in said ambient temperature, said temperature estimation method controlled by said processor to overcome said delayed response, and comprising the steps of: (a) periodically acquiring temperature readings from said temperature sensor when said biosensing meter is both in an ON state and in an OFF state; (b) when said biosensing meter is in said ON state, estimating said ambient temperature by employing at least two most recent temperature readings; and (c) employing said ambient temperature estimated in step (b) to compensate a determined analyte value.
Claim 2
Dependent Claim
144 words
A temperature estimation method for use in a biosensing meter that determines a value of an analyte in a biological sample, a determined analyte value dependent upon an ambient temperature about said biological sample, said biosensing meter including a processor and a temperature sensor, said temperature sensor positioned within said meter and thereby exhibiting a delayed response to changes in said ambient temperature, said temperature estimation method controlled by said processor to overcome said delayed response, and comprising the steps of: (a) periodically acquiring temperature readings from said temperature sensor when said biosensing meter is both in an ON state and in an OFF state; (b) when said biosensing meter is in said ON state, estimating said ambient temperature by employing at least two most recent temperature readings; and (c) employing said ambient temperature estimated in step (b) to compensate a determined analyte value.
Claim 3
Dependent Claim
33 words
The method as recited in claim 1 wherein step b estimates said ambient temperature by using said two most recent temperature readings and extrapolating therefrom to determine said estimate of said ambient temperature.
Claim 4
Dependent Claim
73 words
The method as recited in claim 2 wherein said temperature readings are acquired at first intervals when said meter is in said OFF state, and at second, shorter intervals when said meter is in said ON state, said biosensing meter employing a temperature reading acquired when said meter is in said OFF state and a temperature reading when said meter is in said ON state to determine at least one said temperature estimate.
Claim 5
Dependent Claim
45 words
The method as recited in claim 1 wherein said estimation step is only performed when a difference between said two most recent temperature readings exceeds a threshold value, a latest temperature reading being employed as said ambient temperature when said threshold value is not exceeded.
Claim 6
Dependent Claim
55 words
The method as recited in claim 1 wherein said estimation step extrapolates said two most recent temperature readings T old and T new to obtain T ambient by employing the expression: ##EQU3## Where: m=inverse of the meter's thermal time constant (in seconds); Δt=the time in seconds between acquisition of T new and T old .
Claim 7
Dependent Claim
86 words
The method as recited in claim 5 wherein T old is acquired when said meter is in said OFF state, and said meter is switched to the ON state and a T new reading is acquired, the method comprising the added steps of: determining an elapsed time between when T old and T new values are acquired; comparing said determined elapsed time against a time threshold; and disregarding said T new reading when said elapsed time is not at least equal to said elapsed time threshold.
Claim 8
Dependent Claim
73 words
The method as recited in claim 5, comprising the following added steps of: finding a temperature difference value between T new and T old ; comparing said temperature difference value with a temperature difference threshold value; and employing T new reading as a new T ambient value when said temperature difference value is less than said temperature difference threshold value, based upon an assumption that said biosensing meter is at a stable temperature.
Claim 9
Dependent Claim
34 words
The method as recited in claim 7 wherein said biosensing meter includes a pluggable read only memory chip, and wherein said temperature difference threshold value is acquired from said pluggable read only memory chip.
Claim 10
Dependent Claim
22 words
The method as recited in claim 5, wherein said biosensing meter operates when said T ambient falls within set operating temperature limits.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-04-10 | 1998-10-10 | 1999-04-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-04-10 | 2002-10-10 | 2003-04-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-04-10 | 2006-10-10 | 2007-04-11 | $7700.00 | Window Closed / Lapsed |