A simpler measurement method for galvanic skin response using LM317 IC and its validation

A simpler measurement method for galvanic skin response using LM317 IC and its validation | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Method Article A simpler measurement method for galvanic skin response using LM317 IC and its validation Rajarshi Das, Mainakh Chakroborty, Tarak Das This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9710082/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Galvanic Skin Response (GSR) is also known as Electrodermal Activity (EDA) which is basically a physiological signal which tells us about the variations in skin conductance which is caused by sympathetic nervous system activity. We need a constant current source which will be used as excitation source that helps to measure the GSR accurately, as the skin impedance is too much sensitive to sweat secretion, electrode contacts and other environmental factors. This research paper accentuates the design, application and experimental documentation of a low-cost constant current source made with LM317 IC for the measurement of skin impedance. To deliver a stable current over a wide range of load resistances, the circuit is designed to ensure reliable voltage variations which are proportional to the changes in skin impedance. While performing several tests with the circuit, the results have shown stable constant-current behaviour for different resistive loads which validates the relevance of the design for GSR applications. In addition to this, a future extension using a tetrapolar electrode configuration is proposed to minimize the effects of electrode-skin interface and improve the measurement accuracy. This advanced system provides a simple, robust and an economical solution for biomedical instrumentation and physiological monitoring. Constant Current Source Electrodermal Activity Galvanic Skin Response (GSR) LM317 IC Skin Impedance Tetrapolar Measurement Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9710082","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Method Article","associatedPublications":[],"authors":[{"id":640432251,"identity":"b53c84db-a744-4344-949e-7ceb1c985909","order_by":0,"name":"Rajarshi Das","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABDklEQVRIiWNgGAWjYHCCBCA+wMNwgIHxwcd/NkAOY+MBYrUwG85gSwNpaSCkBQQOgBCbMA/bYRgXNzBvP/Dwc8WfOzJ8x48/Y5zBc95ubfthoC01NtG4tMicSUiWPNv2jEfyTI7Zgw8St5O3nUkEajmWltuAQ4sEQ0KCZGPDYR6DAznshjMMbiebHQBqYWw4jFsL/4Pknw1/gFrOP38mzZNwLtns/EMCWiQS0iQb2IBabiSYSfMcOGBndoOQLRIP0iwb2w7zSN54Y2w4syE5wewG0JYEfH7hz0m+CXSYPd/59IcPPjbY2ZuBGB9qbHBqYWDgSUDhJoJVJmCqQwLsB1C49ngVj4JRMApGwYgEAAshbW4M8Ug+AAAAAElFTkSuQmCC","orcid":"","institution":"Netaji Subhash Engineering College","correspondingAuthor":true,"prefix":"","firstName":"Rajarshi","middleName":"","lastName":"Das","suffix":""},{"id":640432252,"identity":"44f7edc5-e210-408a-89da-fad04feab29d","order_by":1,"name":"Mainakh Chakroborty","email":"","orcid":"","institution":"Netaji Subhash Engineering College","correspondingAuthor":false,"prefix":"","firstName":"Mainakh","middleName":"","lastName":"Chakroborty","suffix":""},{"id":640432255,"identity":"7855bf74-179a-4787-a767-d95c6b6deed9","order_by":2,"name":"Tarak Das","email":"","orcid":"","institution":"Netaji Subhash Engineering College","correspondingAuthor":false,"prefix":"","firstName":"Tarak","middleName":"","lastName":"Das","suffix":""}],"badges":[],"createdAt":"2026-05-14 05:40:14","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9710082/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9710082/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":109289075,"identity":"c7278f2c-b765-4db7-938f-b49b144583da","added_by":"auto","created_at":"2026-05-15 06:10:51","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":649904,"visible":true,"origin":"","legend":"","description":"","filename":"ASimplerMeasurementMethodforGalvanicSkinResponseUsingLM317ICandItsValidation.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9710082/v1_covered_6e43877d-eb7d-4f40-a511-120eec837e6a.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"A simpler measurement method for galvanic skin response using LM317 IC and its validation","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Constant Current Source, Electrodermal Activity, Galvanic Skin Response (GSR), LM317 IC, Skin Impedance, Tetrapolar Measurement","lastPublishedDoi":"10.21203/rs.3.rs-9710082/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9710082/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eGalvanic Skin Response (GSR) is also known as Electrodermal Activity (EDA) which is basically a physiological signal which tells us about the variations in skin conductance which is caused by sympathetic nervous system activity. 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