{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T06:31:27Z","timestamp":1782282687327,"version":"3.54.5"},"reference-count":37,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2020,1,6]],"date-time":"2020-01-06T00:00:00Z","timestamp":1578268800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Romanian Ministry of Research and Innovation","award":["CCDI-UEFISCDI project number 3PCCDI\/2018, within PNCDI III"],"award-info":[{"award-number":["CCDI-UEFISCDI project number 3PCCDI\/2018, within PNCDI III"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper presents the design and implementation of a high sensitivity giant magnetoresistance (GMR) based current sensor with a broad range of applications. The novelty of our approach consists in using a double differential measurement system, based on commercial GMR sensors, with an adjustable biasing system used to linearize the field response of the system. The work aims to act as a fully-operational proof of concept application, with an emphasis on the mode of operation and methods to improve the sensitivity and linearity of the measurement system. The implemented system has a broad current measurement range from as low as 75 mA in DC and 150 mA in AC up to 4 A by using a single setup. The sensor system is also very low power, consuming only 6.4 mW. Due to the way the sensors are polarized and positioned above the U-shaped conductive band through which the current to be measured is flowing, the differential setup offers a sensitivity of about between 0.0272 to 0.0307 V\/A (signal from sensors with no amplifications), a high immunity to external magnetic fields, low hysteresis effects of 40 mA, and a temperature drift of the offset of about \u22122.59\u00d710\u22124 A\/\u00b0C. The system provides a high flexibility in designing applications where local fields with very low amplitudes must be detected. This setup can be redesigned for a wide range of applications, thus allowing further specific optimizations, which would provide an even greater accuracy and a significantly extended operation range.<\/jats:p>","DOI":"10.3390\/s20010323","type":"journal-article","created":{"date-parts":[[2020,1,6]],"date-time":"2020-01-06T10:34:46Z","timestamp":1578306886000},"page":"323","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":44,"title":["High Sensitivity Differential Giant Magnetoresistance (GMR) Based Sensor for Non-Contacting DC\/AC Current Measurement"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4878-5815","authenticated-orcid":false,"given":"Cristian","family":"Mu\u0219uroi","sequence":"first","affiliation":[{"name":"Department of Electrical Engineering and Applied Physics, Transilvania University of Brasov, 29 Blvd. Eroilor, 500036 Brasov, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mihai","family":"Oproiu","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering and Applied Physics, Transilvania University of Brasov, 29 Blvd. Eroilor, 500036 Brasov, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marius","family":"Volmer","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering and Applied Physics, Transilvania University of Brasov, 29 Blvd. Eroilor, 500036 Brasov, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ioana","family":"Firastrau","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering and Applied Physics, Transilvania University of Brasov, 29 Blvd. Eroilor, 500036 Brasov, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,1,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Wang, J., Si, D., Tian, T., and Ren, R. 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