Paul C Ritchie

US Patent:

53523512, Oct 4, 1994

Filed:

Jun 8, 1993

Appl. No.:

8/073180

Inventors:

Bradley E. White - Indianapolis IN
Robert A. Parks - Springport IN
Paul G. Ritchie - Indianapolis IN
Vladimir Svetnik - Carmel IN

Assignee:

Boehringer Mannheim Corporation - Indianapolis IN

International Classification:

G01N 2726

US Classification:

204406

Abstract:

A biosensing meter receives a sample strip that includes electrically isolated sense and excitation electrodes bridged by a reaction zone. When a drop of biological sample fluid is placed in the reaction zone, a plurality of fail/safe tests are performed. A drop size test is performed by a circuit that detects the size of the drop placed in the reaction zone. The circuit both detects that a drop has been placed in the reaction zone and further measures a test current level, after a delay, to determine that the drop size is sufficient to enable hydration of reactants in the reaction zone. Subsequently, during the reaction, a "delta" current change is measured at succeeding sample time. This test measures the difference between succeeding current samples during a measurement time. If each succeeding sample is not less than preceding sample by a delta value, a determination is made that the current is not monotonically decreasing and the test is aborted.

US Patent:

53666097, Nov 22, 1994

Filed:

Jun 8, 1993

Appl. No.:

8/073316

Inventors:

Bradley E. White - Indianapolis IN
Robert A. Parks - Springport IN
Paul G. Ritchie - Indianapolis IN
Terry A. Beaty - Indianapolis IN

Assignee:

Boehringer Mannheim Corporation - Indianapolis IN

International Classification:

G01N 2726

US Classification:

204403

Abstract:

A biosensing meter is enabled to receive a sample strip that includes a sample well with an analyte reactant therein and electrodes in contact therewith. The biosensing meter includes an excitation supply for supplying potentials to a sample strip electrode. A sense amplifier is also provided for connection to another electrode of an inserted sample strip and produces an output signal indicative of sensed currents when an analyte containing fluid is present in the strip's sample well. A pluggable memory key is insertable into the meter and includes a plurality of stored parameter values and procedure routines that control operations of the meter. A microprocessor is responsive to a procedure routine and parameter values accessed from the pluggable memory key to cause the excitation supply to apply a plurality of potentials for preset durations, both the values of the potentials and the time duration of their application determined from parameter values derived from the memory key. The microprocessor controls the sense amplifier to provide a plurality of signal outputs over a predetermined duration, the sense amplifier being operated under control of specific parameter values derived from the pluggable memory key. Replacement of a pluggable memory key with a memory key containing alternative procedures and parameters enables the biosensing meter to carry out substantially modified test procedures without a requirement for modification of the structure of the meter.

US Patent:

54055113, Apr 11, 1995

Filed:

Jun 8, 1993

Appl. No.:

8/073179

Inventors:

Bradley E. White - Indianapolis IN
Michael L. Brown - Greenwood IN
Paul G. Ritchie - Indianapolis IN
Vladimir Svetnik - Carmel IN
Robert A. Parks - Springport IN
Stefan Weinert - Fortville IN

Assignee:

Boehringer Mannheim Corporation - Indianapolis IN

International Classification:

G01N 2726

US Classification:

2041531

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.

US Patent:

54382718, Aug 1, 1995

Filed:

Nov 22, 1994

Appl. No.:

8/343363

Inventors:

Bradley E. White - Indianapolis IN
Robert A. Parks - Springport IN
Paul G. Ritchie - Indianapolis IN

Assignee:

Boehringer Mannheim Corporation - Indianapolis IN

International Classification:

G01R 2702

US Classification:

324444

Abstract:

A biosensing meter receives a biomedical sample strip or a check strip, a sample strip including electrically isolated excitation and sense electrodes. The biosensing meter includes first and second contacts that are positioned to be electrically connected by a sense electrode when a sample strip is inserted into the biosensing meter. An operational amplifier circuit has one input connected to the first contact and a second input connected to a reference potential, the one input manifesting the reference potential as a result of a feedback within the operational amplifier. A processor is coupled to the second contact and determines the presence of the reference potential at the second contact when an inserted sense electrode connects the first and second contacts. The processor also distinguishes between a sample strip and a check strip and, when a sample strip is inserted, that the sample strip exhibits a proper impedance between its sense and excitation electrodes--to enable operation of the biosensing meter upon dosing of the sample strip.