感应耦合热敏电阻

Thisapplicationnotedescribesatemperaturesensor

usingaPICmicro

®

microcontroller.Thistemperature

sensorisuniquebecauseitcanworkthroughnon-fer-

romagneticwalls.Interfacingtoathermistorisnormally

averystraightforwardtask.Interfacingtoathermistor

ontheothersideofawallgetsalittlemorecompli-

cated.Interfacingthroughwallscanbeaveryvaluable

featureincertainapplications,notablytemperature

sensingforrefrigeratorsorsensinginsideofahazard-

ousgasenvironmentwhereanisolationbarrierisa

safetyissue.AN850InductivelyCoupledThermistorThismethodisinappropriateforathroughwalltemper-Author:JosephJulicheraturesystembecauseitrequiresawiretoconnecttheMicrochipTechnologyInc.thermistortothePICmicroMCU.DCcurrentscannotbetransmittedthroughawall,sothismethodcannotbedirectlyconvertedtoathroughwallsystem.INTRODUCTIONTosenseth