<?xml version="1.0" encoding="UTF-8"?>
<records>
<record>
<language>eng</language>
<publisher>Science and Education Publishing</publisher>
<journalTitle>American Journal of Sensor Technology</journalTitle>
<eissn>2373-3462</eissn>
<publicationDate>2018-12-14</publicationDate>
<volume>5</volume>
<issue>1</issue>
<startPage>7</startPage>
<endPage>16</endPage>
<doi>10.12691/ajst-5-1-2</doi>
<publisherRecordId>AJST2018512</publisherRecordId>
<documentType>article</documentType>
<title language="eng">Single-chip Implementation of LVDT Signal Conditioning</title>
<authors>
<author>
<name>Lars E. Bengtsson</name>
<email>lars.bengtsson@physics.gu.se</email>
<affiliationId>1</affiliationId>
</author>
</authors>
<affiliationsList>
<affiliationName affiliationId="1">Department of Physics, University of Gothenburg, Gothenburg, Sweden</affiliationName>

</affiliationsList>
<abstract language="eng">The aim of this work was to prove that the signal conditioning electronics for linear variable transformers (LVDTs) can be implemented in inexpensive, general-purpose 8-bit microcontrollers, making expensive dedicated signal conditioning chips redundant. A low-cost, high-resolution signal conditioning solution for LVDTs is presented. Apart from a few external passive components, the entire solution is implemented in a low-cost, analog-digital hybrid microcontroller. The excitation sinusoid is generated by filtering out the fundamental frequency of a (self-sustained) pwm-generated square wave and the secondary coils' signals are demodulated with classic peak detector circuits implemented in the microcontroller using a combination of its embedded analog and digital building blocks. A resolution of 1 m over a range of &#177;6.35 mm for a commercial LVDT is reported and an uncertainty of 6 m in the absolute value is deduced. The entire solution is implemented as surface mounted components on a small printed circuit board and the LVDT core displacement is displayed on an LCD display. Due to the simplicity and low-cost components required, this signal conditioning proposal has the potential to have a significant impact on commercial LVDT signal conditioning chips in the future since it is significantly less expensive than the present state-of-the-art signal conditioning chips offered by the main commercial suppliers and other solutions previously suggested in scientific literature.</abstract>
<fullTextUrl format="pdf">http://pubs.sciepub.com/ajst/5/1/2/ajst-5-1-2.pdf</fullTextUrl>
<keywords language="eng"><keyword>displacement sensor</keyword>
<keyword>demodulation</keyword>
<keyword>excitation</keyword>
<keyword>LVDT</keyword>
<keyword>microcontroller</keyword>
<keyword>peak detector</keyword>
</keywords>
</record>
</records>
