Variable resistor arrangement, measurement bridge circuit and method for calibrating a measurement bridge circuit

Patent metadata

Field	Value
Publication number	US-9568523-B2
Application number	US-201214353758-A
Country	US
Kind code	B2
Filing date	Sep 6, 2012
Priority date	Nov 2, 2011
Publication date	Feb 14, 2017
Grant date	Feb 14, 2017

Abstract

A measurement bridge circuit includes a first branch and a second branch. The first branch contains a first resistor which is sensitive to measured variables and an invariable resistor connected in series. A first tap point is located between the first resistor and the invariable resistor. The second branch contains a second resistor which is sensitive to measured variables and a variable resistor arrangement connected in series. The variable resistor arrangement includes a first component having an invariable electrical resistance value and a second component having a variable electrical resistance value. The second component is connected in parallel with the first component in order to vary a total electrical resistance value for the variable resistor arrangement. A second tap point is located between the second resistor and the variable resistor arrangement.

First claim

The invention claimed is:

1. A measurement bridge circuit, comprising:
a first branch including a first resistor connected in series with an invariable resistor;
a first tap point located between the first resistor and the invariable resistor;
a second branch including a second resistor connected in series with a variable resistor arrangement having (i) a first component with an invariable electrical resistance value, and (ii) a memristor with a variable electrical resistance value, the memristor connected in parallel with the first component and configured to vary a total electrical resistance value of the variable resistor arrangement; and
a second tap point located between the second resistor and the variable resistor arrangement,
wherein the first branch and the second branch are connected in parallel and a measuring instrument is configured to be arranged between the first tap point and the second tap point.

2. The measurement bridge circuit as claimed in claim 1 , wherein at least one of the first resistor and the second resistor is a resistor which is sensitive to measured variables and is configured to map a change in a physical variable at a sensor in a corresponding change in an electrical resistance value.

3. The measurement bridge circuit as claimed in claim 1 , wherein the variable resistor arrangement includes at least one externally accessible calibration connection.

4. The measurement bridge circuit as claimed in claim 1 , wherein the measuring instrument at least includes a voltage measuring device connected between the first tap point and the second tap point and configured to measure a voltage between the first tap point and the second tap point.

5. A method for calibrating a measurement bridge circuit including a first branch and a second branch, comprising:
determining a measured value of a measuring instrument when a first resistor of the first branch is subjected to a physical calibration variable and a second resistor of the second branch is likewise subjected to a physical calibration variable; and
varying the electrical resistance value of a memristor of a variable resistor arrangement until the measured value is in a tolerance range by a predetermined value in order to calibrate the measurement bridge circuit,
wherein the first branch includes the first resistor connected in series with an invariable resistor,
wherein a first tap point of the measurement bridge circuit is located between the first resistor and the invariable resistor,
wherein the second branch includes the second resistor connected in series with the variable resistor arrangement,
wherein the variable resistor arrangement includes a first component with an invariable electrical resistance value and the memristor,
wherein the memristor has a variable electrical resistance value and is connected in parallel with the first component and configured to vary a total electrical resistance value of the variable resistor arrangement,
wherein a second tap point of the measurement bridge circuit is located between the second resistor and the variable resistor arrangement, and
wherein the first branch and the second branch are connected in parallel and the measuring instrument is configured to be arranged between the first tap point and the second tap point.

6. The method as claimed in claim 5 , wherein at least one of:
in varying the electrical resistance value, the electrical resistance value is increased continuously until the measured value departs from the tolerance range, and an interval of the electrical resistance value between the measured value entering the tolerance range and the measured value departing from the tolerance range is determined, the electrical resistance value is then decreased continuously by a predetermined proportion of the interval, the predetermined proportion being half of the interval; and
in varying the electrical resistance value, the electrical resistance value is decreased continuously until the measured value departs from the tolerance range and the interval of the electrical resistance value between the measured value entering the tolerance range and the measured value departing from the tolerance range is determined, the electrical resistance value is then increased continuously by a predetermined proportion in order to calibrate the measurement bridge circuit.

7. A control device for calibrating a measurement bridge circuit including a first branch and a second branch, the control device being configured to:
determine a measured value of a measuring instrument when a first resistor of the first branch is subjected to a physical calibration variable and a second resistor of the second branch is likewise subjected to a physical calibration variable; and
vary the electrical resistance value of a memristor of a variable resistor arrangement until the measured value is in a tolerance range by a predetermined value in order to calibrate the measurement bridge circuit,
wherein the first branch includes the first resistor connected in series with an invariable resistor,
wherein a first tap point of the measurement bridge circuit is located between the first resistor and the invariable resistor,
wherein the second branch includes the second resistor connected in series with the variable resistor arrangement,
wherein the variable resistor arrangement includes a first component with an invariable electrical resistance value and the memristor,
wherein the memristor has a variable electrical resistance value and is connected in parallel with the first component and configured to vary a total electrical resistance value of the variable resistor arrangement,
wherein a second tap point of the measurement bridge circuit is located between the second resistor and the variable resistor arrangement, and
wherein the first branch and the second branch are connected in parallel and the measuring instrument is configured to be arranged between the first tap point and the second tap point.

8. The control device according claim 7 , wherein the control device is configured to run a computer program product that includes program code.

Assignees

• Herrmann Ingo
• Mueller-Fiedler Roland
• Krueger Veronique
• Bosch Gmbh Robert

Inventors

• Herrmann Ingo
• Mueller-Fiedler Roland
• Krueger Veronique

Classifications

• G01R35/005 Primary

  Calibrating; Standards or reference devices, e.g. voltage or resistance standards, "golden" references (G01R33/0035, G01R35/002 take precedence) · CPC title

• H01C10/16

  including plural resistive elements · CPC title

• G01R27/02 Primary

  Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant (by measuring phase angle only G01R25/00) · CPC title

• G01R17/10

  AC or DC measuring bridges · CPC title