Active measurement correction of resistive sensors

Patent metadata

Field	Value
Publication number	US-11747379-B2
Application number	US-202217592934-A
Country	US
Kind code	B2
Filing date	Feb 4, 2022
Priority date	Mar 10, 2021
Publication date	Sep 5, 2023
Grant date	Sep 5, 2023

Abstract

In an embodiment, an apparatus is disclosed that comprises a plurality of resistors arranged as a reverse bridge and configured to convert an input voltage to a scaled output voltage. The scaled output voltage is scaled to a target format based at least in part on a range of the input voltage and a fixed value of the plurality of resistors. The input voltage is generated based at least in part on at least one signal generated by a sensor based at least in part on a measurement of a property of a measurement target. At least one of the plurality of resistors has a resistance value of R and at least another of the plurality of resistors has a resistance value of R plus or minus ΔR.

First claim

What is claimed is:

1. An apparatus comprising:
a plurality of resistors arranged as a reverse bridge and being configured to convert an input voltage to a scaled output voltage, the scaled output voltage being scaled to a target format based at least in part on a range of the input voltage and a fixed value of the plurality of resistors, the input voltage being generated based at least in part on at least one signal generated by a sensor based at least in part on a measurement of a property of a measurement target,
wherein at least one of the plurality of resistors has a resistance value of R and at least another of the plurality of resistors has a resistance value of R plus or minus ΔR.

2. The apparatus of claim 1 , wherein the input voltage is generated by a sensor signal conditioning integrated circuit based at least in part on the at least one signal generated by the sensor.

3. The apparatus of claim 2 , wherein the range of the input voltage is based at least in part on a supply voltage (VDD) of the sensor signal conditioning integrated circuit.

4. The apparatus of claim 3 , wherein the target format comprises a target voltage value per VDD per unit of pressure (P).

5. The apparatus of claim 4 , wherein the target format comprises one of:
5 microvolts (μV)/VDD/P; and
40 μV/VDD/P.

6. The apparatus of claim 1 , wherein the plurality of resistors comprise four resistors, the four resistors comprising one of:
three resistors having a resistance value of R and one resistor having a resistance value of R+ΔR;
two resistors having a resistance value of R and two resistors having a resistance value of R+ΔR;
two resistors having a resistance value of R, one resistor having a resistance value of R+ΔR and one resistor having a resistance value of R−ΔR; and
two resistors having a resistance value of R+ΔR and two resistors having a resistance value of R−ΔR.

7. The apparatus of claim 1 , wherein the fixed value of the plurality of resistors is one or more of a fixed value of R, a fixed value of ΔR, a fixed ratio of ΔR/R and a fixed ratio of ΔR/(R+ΔR/2).

8. The apparatus of claim 1 , wherein the input voltage is connected to a first portion of the reverse bridge and a voltage source is connected to a second portion of the reverse bridge, the reverse bridge being configured to generate a negative scaled output voltage based at least in part on the connection of the second portion of the reverse bridge to the voltage source.

9. A system comprising:
a sensor signal conditioning integrated circuit, the sensor signal conditioning integrated circuit being configured to:
receive at least a first sensor signal and a second sensor signal from a sensor, the first and second sensor signals being generated by the sensor based at least in part on a measurement of a property of a measurement target; and
generate an input voltage based at least in part on a differential voltage between the first and second sensor signals, the input voltage having a range that is proportional to a measurement range the property of the measurement target that is being measured by the sensor; and

a plurality of resistors arranged as a reverse bridge, the reverse bridge being configured to convert the input voltage to a scaled output voltage, the scaled output voltage being scaled to a target format based at least in part on the range of the input voltage and a fixed value of the plurality of resistors.

10. The system of claim 9 , wherein:
the differential voltage between the first and second sensor signals is a nonlinear temperature dependent value generated as a function of the property of the measurement target being measured by the sensor; and
the sensor signal conditioning integrated circuit is configured to generate the input voltage based at least in part on a linearization of the first and second sensor signals.

11. The system of claim 9 , wherein sensor signal conditioning integrated circuit is configured to receive a supply voltage (VDD) and the range of the input voltage is based at least in part on VDD.

12. The system of claim 11 , wherein the target format comprises a target voltage value per VDD per unit of pressure (P).

13. The system of claim 12 , wherein the target format comprises one of:
5 microvolts (μV)/VDD/P; and
40 μV/VDD/P.

14. The system of claim 9 , wherein at least one of the resistors has a resistance value of R and at least another of the resistors has a resistance value of R plus or minus ΔR.

15. The system of claim 14 , wherein the plurality of resistors comprise four resistors, the four resistors comprising one of:
three resistors having a resistance value of R and one resistor having a resistance value of R+ΔR;
two resistors having a resistance value of R and two resistors having a resistance value of R+ΔR;
two resistors having a resistance value of R, one resistor having a resistance value of R+ΔR and one resistor having a resistance value of R−ΔR; and
two resistors having a resistance value of R+ΔR and two resistors having a resistance value of R−ΔR.

16. The system of claim 14 , wherein the fixed value of the plurality of resistors is one or more of a fixed value of R, a fixed value of ΔR, a fixed ratio of ΔR/R and a fixed ratio of ΔR/(R+ΔR/2).

17. The system of claim 9 , wherein the input voltage is connected to a first portion of the reverse bridge and a voltage source is connected to a second portion of the reverse bridge, the reverse bridge being configured to generate a negative scaled output voltage based at least in part on the connection of the second portion of the reverse bridge to the voltage source.

18. A system comprising:
a sensor signal conditioning integrated circuit, the sensor signal conditioning integrated circuit being configured to:
receive at least a first sensor signal and a second sensor signal from a sensor, the first and second sensor signals being generated by the sensor based at least in part on a measurement of a fluid pressure corresponding to a pressure monitor of a patient; and
generate an input voltage based at least in part on a differential voltage between the first and second sensor signals, the input voltage having a range that is proportional to a measurement range the fluid pressure that is being measured by the sensor; and

a plurality of resistors arranged as a reverse bridge, the reverse bridge being configured to:
convert the input voltage to a scaled output voltage, the scaled output voltage being scaled to a target format based at least in part on the range of the input voltage and a fixed value of the plurality of resistors; and
provide the scaled output voltage to a presentation device.

19. The system of claim 18 , wherein:
wherein at least one of the resistors has a resistance value of R and at least another of the resistors has a resistance value of R plus or minus ΔR; and
the fixed value of the plurality of resistors is one or more of a fixed value of R, a fixed value of ΔR, a fixed ratio of ΔR/R and a fixed ratio of ΔR/(R+ΔR/2).

Assignees

• Renesas Electronics America Inc

Inventors

• Grice David Mitchell

Classifications

• G01R27/2629 Primary

  Bridge circuits (bridges for measuring loss angle G01R27/2694) · CPC title

• G01R35/005

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

• G01D5/16 Primary

  by varying resistance · CPC title

• G01D3/021 Primary

  using purely analogue techniques · CPC title

• G01D3/028

  mitigating undesired influences, e.g. temperature, pressure · CPC title