价格:未填
供应:99999
发货:3天内
TIREPRESSUREMONITORINGSENSOROPTIMIZEDFOR250kPa 450kPaGENERALDESCRIPTIONTheMotorolaMPXY8020Aisan8 pintiremonitoringsensorwhichiscomprisedofavariablecapacitancepressuresensingelement,atemperaturesensingelement,andaninterfacecircuit(withawake upfeature)allonasinglechip.ItishousedinaSuper SmallOutlinePackage(SSOP),whichincludesamediaprotectionfilter.Specificallydesignedforthelowpowerconsumptionrequirementsoftirepressuremonitoringsystems,itcancombinewithaMotorolaremotekeylessentry(RKE)systemtofacilitatealow costhighlyintegratedsystem.DetailedDescriptionTheblockdiagramoftheMPXY8020AisshowninFigure1.Thepressuresensorisacapacitivetransducerconstructedusingsurfacemicromachining,thetemperaturesensorisconstructedusingadiffusedresistor,andtheinterfacecircuitisintegratedontothesamedieasthesensorsusingastandardsiliconCMOSprocess.Theconditioningofthepressuresignalbeginswithacapacitancetovoltageconversion(CtoV)followedbyaswitchedcapacitoramplifier.Thisamplifierhasadjustableoffsetandgaintrimming.Theoffsetandgainarefactorycalibrated,withcalibrationvaluesstoredintheEEPROMtrimregister.Thisamplifieralsohastemperaturecompensationcircuitsforbothsensitivityandoffset,whichalsoarefactory adjustedusingtheEEPROMtrimregister.Thepressureismonitoredbyavoltagecomparator,whichcomparesthemeasuredvalueagainstan8 bitthresholdadjustedbyaserialinput.ByadjustingthethresholdandmonitoringthestateoftheOUTpintheexternaldevicecancheckwhetheralow pressurethresholdhasbeencrossed,orperformupto8 bitA/Dconversions.Thetemperatureismeasuredbyadiffusedresistorwithapositivetemperaturecoefficientdrivenbyacurrentsource,therebycreatingavoltage.Theroomtemperaturevalueofthisvoltageisfactory calibratedusingtheEEPROMtrimregister.Atwo channelmultiplexercanrouteeitherthepressureortemperaturesignaltoasamplingcapacitorthatismonitoredbyavoltagecomparatorwithvariablethresholdadjust,providingadigitaloutputfortemperature.Aninternallowfrequency,lowpower5.4kHzoscillatorwitha14 stagedividerprovidesaperiodicpulsetotheOUTpin(divideby16384for3seconds).ThispulsecanbeusedtowakeupanexternalMCUtobeginaninterfacewiththedevice.Anadditional10 stagedividerwillprovideapulseevery52minuteswhichcanbeusedtoresetanexternalMCU.Thepowerconsumptioncanbecontrolledbyseveraloperationalmodesselectedbyexternalpins.本公司库存量大，为减小库存，现特价处理