Noise measurement and system calibration on magnetoresistive sensors
ISSN: 0260-2288
Article publication date: 26 April 2023
Issue publication date: 9 May 2023
Abstract
Purpose
The noise measurement on magnetoresistive (MR) sensors is generally conducted by techniques including single-channel data sampling and fast Fourier transform (FFT) analysis as well as two-channel cross-correlation. The single-channel method is easy to implement and is widely used in the noise measurement on MR sensors, whereas the two-channel method can only eliminate part of the system noise. This study aims to address two key issues affecting measurement accuracy: calibration of the measurement system and the elimination of system noise.
Design/methodology/approach
The system is calibrated by using a low-noise metal film resistor in that the system noise is eliminated through power spectrum subtraction. Noise measurement and analysis are conducted for both thermal noise and detectivity of magnetic tunnel junction (MTJ) sensor.
Findings
The thermal noise measurement error is less than 2%. The detectivity of the MTJ sensor reaches 27 pT/Hz1/2 at 2 kHz.
Originality/value
This study provides a more practical solution for noise measurement and system calibration on MR sensors with a bias voltage and magnetic field.
Keywords
Acknowledgements
This work was supported by the Fundamental Research Funds for the Provincial Universities of Zhejiang of China (Grant No. GK229909299001-05), the National Key Research and Development Program of China (Grant No. 2018YFF01010701) and Zhejiang Province Public Welfare Projects of China (Grant No. LGG22F030017).
Citation
Dou, A., Bai, R., Zhu, H. and Qian, Z. (2023), "Noise measurement and system calibration on magnetoresistive sensors", Sensor Review, Vol. 43 No. 3, pp. 200-207. https://doi.org/10.1108/SR-07-2022-0284
Publisher
:Emerald Publishing Limited
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