Corrected temperature sensor measurement

• US 10,088,855 B2
• Filed: 05/13/2015
• Issued: 10/02/2018
• Est. Priority Date: 05/13/2015
• Status: Active Grant

• Current Assignee: Infineon Technologies AG
• Original Assignee: Infineon Technologies AG
• Inventors: Ma, Fan Yung
• Primary Examiner(s): Shah, Manish S
• Application Number:
  US14/710,802
• Publication Number:
  US 20160336947A1
• Time in Patent Office: 1,238 Days
• CPC Class Codes: G01K 2219/00 Thermometers with dedicated analog to digital converters
• CPC Class Codes: G01K 7/01 using semiconducting elements having PN junctions G01K7/02, G01K7/16, G01K7/30 take precedence
• CPC Class Codes: G01K 7/21 for modifying the output characteristic, e.g. linearising
• CPC Class Codes: G05F 1/463 Sources providing an output which depends on temperature

Abstract

Representative implementations of devices and techniques provide correction for temperature sensor measurement error. In an example, the temperature sensor includes an analog-to-digital converter (ADC). The ADC output is error corrected using an iterative digital post-processing technique.

Claims

1. An apparatus, comprising:

a first module arranged to receive an output signal from a temperature sensor, the output signal comprising a correct measurement value and an error value; and

a second module arranged to iteratively multiply the output signal by a correction function until convergence of the error value, wherein the correction function comprises an approximation of an inverse of a temperature variation of a reference voltage of the temperature sensor.

2. The apparatus of claim 1, further comprising an iteration loop between the first module and the second module, the iteration loop arranged to be closed until convergence of the error value.

3. The apparatus of claim 2, wherein the first module is arranged to update the error value with each iteration while the iteration loop is closed, the update including subtracting the output signal from a result of the multiplying the output signal by the correction function.

4. The apparatus of claim 2, wherein the second module is arranged to update a value of the output signal after each iteration, wherein a value of a next output signal is updated to equal a result of multiplying a value of a previous output signal by the correction function.

5. The apparatus of claim 1, wherein one of the first module and the second module is arranged to output the correct measurement at convergence of the error value.

6. The apparatus of claim 1, wherein the reference voltage is based on a base-emitter voltage of one or more bipolar devices or a difference between base-emitter voltages of two or more bipolar devices.

7. The apparatus of claim 1, wherein the second module is arranged to iteratively multiply the output signal by the correction function until a magnitude of the error value is less than or equal to a predefined threshold value.

8. The apparatus of claim 1, wherein a magnitude of the error value is reduced with each iteration.

9. A correction circuit, the circuit comprising:

a first module arranged to receive an output signal from a temperature sensor, the output signal comprising a correct measurement value and an error value; and

a second module arranged to iteratively multiply the output signal by a correction function until convergence of the error value, wherein the second module is arranged to iteratively multiply the output signal by the correction function until a magnitude of the error value is less than or equal to a predefined threshold value.

10. The circuit of claim 9, further comprising an iteration loop between the first module and the second module, the iteration loop arranged to be closed until convergence of the error value.

11. The circuit of claim 10, wherein the first module is arranged to update the error value with each iteration while the iteration loop is closed, the update including subtracting the output signal from a result of the multiplying the output signal by the correction function.

12. The circuit of claim 10, wherein the second module is arranged to update a value of the output signal after each iteration, wherein a value of a next output signal is updated to equal a result of multiplying a value of a previous output signal by the correction function.

13. The circuit of claim 9, wherein one of the first module and the second module is arranged to output the correct measurement at convergence of the error value.

14. The circuit of claim 9, wherein the correction function comprises an approximation of an inverse of a temperature variation of a reference voltage of the temperature sensor.

15. The circuit of claim 14, wherein the reference voltage is based on a base-emitter voltage of one or more bipolar devices or a difference between base-emitter voltages of two or more bipolar devices.

16. The circuit of claim 9, wherein a magnitude of the error value is reduced with each iteration.