<abstract xmlns="http://www.w3.org/1999/xhtml">

Pt100 is a resistance temperature detector characterized by a relatively linear resistance/temperature relationship in a narrow temperature range. However, the Pt100 sensor shows a certain degree of static transfer function nonlinearity of 4.42 % in the range between −200 °C and 850 °C, which is unacceptable for some applications. As a solution to this problem, a mixed-mode linearization method based on a special dual-stage piecewise linear ADC design is proposed in this paper. The first stage of the proposed dual-stage piecewise linear ADC is performed with a low-complex and low-power flash ADC of a novel sequential design. The novelty of the proposed sequential design is reflected in the fact that the number of employed comparators is equal to the flash ADC resolution. The second stage is performed with a delta-sigma ADC with a differential input and differential reference. Using the 6-bit flash ADC of novel design and the 24-bit delta-sigma ADC, the nonlinearity error is reduced to 2.6·10−3 %, in the range between −200 °C and 850 °C. Two more ranges are examined, and the following results are obtained: in the range between 0 °C and 500 °C, the nonlinearity error is reduced from 1.99 % to 5·10−4 %, while in the range between −50 °C and 150 °C, the nonlinearity error is reduced from 0.755 % to 2.15·10−4 %.
</abstract>

Pt100 is a resistance temperature detector characterized by a relatively linear resistance/temperature relationship in a narrow temperature range. However, the Pt100 sensor shows a certain degree of static transfer function nonlinearity of 4.42 % in the range between −200 °C and 850 °C, which is unacceptable for some applications. As a solution to this problem, a mixed-mode linearization method based on a special dual-stage piecewise linear ADC design is proposed in this paper. The first stage of the proposed dual-stage piecewise linear ADC is performed with a low-complex and low-power flash ADC of a novel sequential design. The novelty of the proposed sequential design is reflected in the fact that the number of employed comparators is equal to the flash ADC resolution. The second stage is performed with a delta-sigma ADC with a differential input and differential reference. Using the 6-bit flash ADC of novel design and the 24-bit delta-sigma ADC, the nonlinearity error is reduced to 2.6·10−3 %, in the range between −200 °C and 850 °C. Two more ranges are examined, and the following results are obtained: in the range between 0 °C and 500 °C, the nonlinearity error is reduced from 1.99 % to 5·10−4 %, while in the range between −50 °C and 150 °C, the nonlinearity error is reduced from 0.755 % to 2.15·10−4 %.

Mixed-mode Method Used for Pt100 Static Transfer Function Linearization

Department of Measurements, Faculty of Electronic Engineering

Measurement Science Review

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

{"article-title":"Mixed-mode Method Used for Pt100 Static Transfer Function Linearization"}

Pt100 is a resistance temperature detector characterized by a relatively linear resistance/temperature relationship in a narrow temperature range. However, the...

Mixed-mode Method Used for Pt100 Static Transfer Function Linearization

Published Online: Sep 17, 2021

Page range: 142 - 149

Received: Jul 14, 2021

Accepted: Aug 25, 2021

DOI: https://doi.org/10.2478/msr-2021-0020

Keywords
Flash ADC, mixed-mode method, nonlinearity compensation, Pt100 static transfer function, sequential design

© 2021 Jelena Jovanović et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Mixed-mode Method Used for Pt100 Static Transfer Function Linearization

Published Online: Sep 17, 2021

Page range: 142 - 149

Received: Jul 14, 2021

Accepted: Aug 25, 2021

DOI: https://doi.org/10.2478/msr-2021-0020

KeywordsFlash ADC, mixed-mode method, nonlinearity compensation, Pt100 static transfer function, sequential design

© 2021 Jelena Jovanović et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Keywords
Flash ADC, mixed-mode method, nonlinearity compensation, Pt100 static transfer function, sequential design