电气英语证书考试(PEC)-电气专有名词1

电气英语证书考试(PEC)-GlossaryofElectrical

EngineeringTerms1

1-WireAsingle-wire(plusground)communicationsprotocol.

1-WireMasterA1-Wireinterfacemastercontroller.

10GbE10-GigabitEthernet

3GThird-generationmobiletelephoneprotocolsthatsupporthigherdata

rates,fornon-voicecommunicationssuchasmultimediaandInternet

access.

3GPPThirdGenerationPartnershipProject,acollaborationofcellphone

technologystandardsbodies.

802.11IEEEstandardthatspecifiesmedium-accessandphysical-layer

specificationsfor1Mbpsand2Mbpswirelessconnectivitybetween

fixed,portable,andmovingstationswithinalocalarea.

802.11aTheIEEEstandardthatgovernsthedeploymentof5GHzOFDM

systems.Itspecifiestheimplementationofthephysicallayerfor

wirelessUNIIb.

802.11bAninternationalIEEEstandardforWLANnetworks,operatingat

2.4GHzandprovidingamaximumdatatransferrateof11Mbps.

802.11gAproposedstandardthatdescribesawirelessnetworkingmethodfora

WLANthatoperatesinthe2.4GHzradioband(ISM:IndustrialScientific

Medicalfrequencyband).Ittransfersdataatupto54Mbps.

A-WeightingA-weightingisastandardweightingcurveappliedtoaudio

measurements,designedtoreflecttheresponseofthehumanear.

Sound-pressurelevelsderivedusingA-weightingaredenotedby"dBA,"

orA-weighteddBlevels.

A/DConverterAnalogtodigital.Specifically:A/Dconverter,acircuitthatconverts

analogsignalsintoastreamofdigitaldata.

ACAlternatingcurrent:Asignalorpowersourcethatvarieswithtime,

switchingpolarities.Typically,sinusodialandconstantfrequency.

AccelerometerAsensorortransducerformeasuringacceleration.

ACPIAdvancedConfigurationandPowerInterface:Anindustry-standard

specification(co-developedbyHewlett-Packard,Intel,Microsoft,

Phoenix,andToshiba)foroperating-system-directedpower

managementforlaptop,desktop,andservercomputers.Areplacement

forAPM.

ACPRAdjacent(alternate)-channelpowerratio

ACRAccumulatedcurrentregister

ADMAdd/DropMultiplexer:Asynchronoustransmissionnetwork(SDHor

Sonet)cancarrymultiplechannels.AnAdd/DropMultiplexerisadevice

thatadds(inserts)ordrops(removes)lower-data-ratechanneltraffic

fromthehigher-rateaggregatedchannel.

ADPCMAdaptiveDifferentialPulseCodeModulation:Acompressiontechnique

thatencodesonlythedifferencebetweensequentialsamples.

ADSAnalogdesignsystem

ADSLAsymmetricDigitalSubscriberLine:Amethodformovingdataover

regularphonelines.AnADSLcircuitcarriesmuchmoredatathana

modemcanencodeonaregularphoneconnection.ADSLridesonthe

regularphonewirescomingintothesubscriber'spremises(twistedpair

copper).

AEC-Q100Aqualificationtestsequenceforintegratedcircuitsdevelopedbythe

AIAGautomotiveorganization.

AFEAnalogFrontEnd:TheanalogportionofacircuitwhichprecedesA/D

conversion.

AGCAutomaticGainControl:Acircuitthatmodulatesanamplifier'sgain,in

responsetotherelativestrengthoftheinputsignal,inordertomaintain

theoutputpower.

AhAmpere-hour(s):Ameasureofbatterycapacity.A4Ahbatterycould,for

instance,deliver1Afor4hours,1/2Afor8hours,etc.

AirDischargeAmethodfortestingESD-protectionstructuresinwhichtheESD

generatorisdischargedthroughanairgapbetweenthegeneratorand

thedeviceundertest(DUT).

AISAlarmindicationsystem

AISGTheAntennaInterfaceStandardsGroup(AISG)createsopen

specificationsforantenna-linecontrolandmonitoringfor3Gsystems.

Source:

AliasingInA/Dconversion,theNyquistprinciplestatesthatthesamplingrate

mustbeatleasttwicethemaximumbandwidthoftheanalogsignal.If

thesamplingrateisinsufficient,thenhigher-frequencycomponentsare

"undersampled"andappearshiftedtolower-frequencies.These

frequency-shiftedcomponentsarecalledaliases.

Thefrequenciesthatshiftaresometimescalled"folded"frequencies

becauseaspectralplotlookslikeitwasfoldedtosuperimposethe

higherfrequencycomponentsoverthesub-Nyquistportionoftheband.

AMAmplitudeModulation:Amodulationmethodinwhichthecarrier

amplitudechangeswiththeinputsignalamplitude.

AmbientTemperatureoftheairsurroundingacomponent.

Temperature

AmbientTemperaturesensorusedtomeasurethetemperatureoftheairthat

Temperaturesurroundsacomponent(theambienttemperature).

Sensor

AMLCDActive-matrixliquid-crystaldisplay

Amp1.Ampere

2.Amplifier

AmpacityTheamountofcurrentaconductorcancarrywithoutexceedingits

specifiedtemperature,inamperes.

AmpereAmpere(s),theunitofelectricalcurrent.Currentisdefinedasthe

amountofchargethatflowspastagivepoint,perunitoftime.

ThesymbolIisusedforcurrentinequationsandAistheabbreviation

forampere.

Ampere-hourAmeasureofcharge(orcurrentflowovertime).

Oneampere-hour(oramp-hourorAh)isacurrentofone

ampereflowingforonehour.Theamountofchargetransferredinthat

houris3,600coulombs(ampere-seconds).

Amilliampere-hour(mAhormilliamp-hour)isathousandthof

anamp-hour.

Anampere-second(A-soramp-second)isanampsuppliedfor

onesecond.

Acommonuseofthetermisratingenergystoragedevicecapacity,

especiallyrechargeablebatteries.Forexample,a12-volt,7Ah

rechargeablebatteryusedinanalarmsystemwillsupplyanampatthe

ratedvoltagerangeforsevenhours,2ampsfor3.5hours,etc.Ifmy

alarmconsumes250mA,thisbatterywouldoperatethesystemfor28

hours.

AmplifierAnelectricalcircuitthatproducesanoutputthatisareplicaoftheinput.

Theoutputmaybescaledorhaveincreaseddrive,oritmayprovide

isolation(sochangesinoutputconditionsdonotaffecttheinputorother

outputs).Itmayperformothertransformations(e.g.,filteringor

logarithmicdrive).

AmplifierClassAmplifiercircuittypesaredividedinto"classes"whichdescribewhether

theamplifieroperatesinalinearorswitchingmode,andanytechniques

usedtorestorelinearityofoutput.

AMPSAdvancedMobilePhoneSystem:Ananalogonly,1Gstandardthat

operatesinthe800MHzto900MHzfrequencyband.Itisstillwidely

usedintheUnitedStates.

AMRAutomaticMeterReading:Asysteminstalledtoreadautilitymeter

remotely.

AnalogAsysteminwhichanelectricalvalue(usuallyvoltageorcurrent,but

sometimesfrequency,phase,etc.)representssomethinginthephysical

world.Theelectricalsignalcanthenbeprocessed,transmitted,

amplified,andfinally,transformedbackintoaphysicalquality.

Forexample:Amicrophoneproducesacurrentthatisproportionalto

soundpressure.Variousstagesamplify,process,modulate,etc.

Ultimately,avaryingvoltageispresentedtoaspeakerwhichconvertsit

backtosoundwaves.

Bycontrast,adigitalsystemhandlesasignalasastreamofnumbers.

AnalogSwitchAnanalogswitch(sometimesjustcalleda"switch")isaswitching

devicecapableofswitchingorroutinganalogsignals(meaningsignals

thatcanhaveanylevelwithinaspecifiedlegalrange),basedonthe

levelofadigitalcontrolsignal.Commonlyimplementedusinga

"transmissiongate,"ananalogswitchperformsafunctionsimilartothat

ofarelay.

Forexample,ananalogswitchcanturnanaudiosignalonoroffbased

onaMUTEsignal;oranalogswitchescouldsendoneoftwosignalsto

aheadphoneamplifier.

MostcommonlyimplementedusingCMOStechnologyintegrated

circuits.Maximmakeshundredsofexamples.

AnalogTemperaturesensorwithacontinuousanalogvoltageorcurrentoutput

Temperaturethatisrelated,usuallylinearly,tothemeasuredtemperature.

Sensor

ANDCombiningtwosignalssothattheoutputisonifbothsignalsare

present.ThiscanbeaccomplishedbyanANDlogicgate(twoinputs,

oneoutputwhichishighifbothinputsare).

ANSIAmericanNationalStandardsInstitute

Anti-AliasingAnanti-aliasingfilterisusedbeforeA/Dconversion.Itisalowpassfilter

thatremovessignalcomponentsabovetheNyquistfrequency,thereby

eliminatingtheirsampledreplicas(aliases)inthebaseband.

APCAutomaticPowerControl:Featureinlaserdrivers(suchasthe

MAX3669)thatusesfeedbackfromthelasertoadjustthedrive,tokeep

thelaser'soutputconstant.

APDAvalanchePhotoDiode:Aphotodiodedesignedtotakeadvantageof

avalanchemultiplicationofphotocurrenttoprovidegain.Asthe

reverse-biasvoltageapproachesthebreak-downvoltage,hole-electron

pairscreatedbyabsorbedphotonsacquiresufficientenergytocreate

additionalhole-electronpairswhentheycollidewithions.Thusa

multiplicationorsignalgainisachieved.

APIApplicationprograminterface:Asoftwarelayerthatallowsasystemto

beprogrammedviaadefinedsetofcommands.

APMAdvancedPowerManagement:Powermanagementstandardfor

computersthatprovidesfivepowerstates:Ready,Stand-by,

Suspended,Hibernation,Off.

APONATM(-based)passiveopticalnetwork

APQPAdvancedProductQualityPlanning.SystemdevelopedbytheAIAG

automotiveorganizationtocommunicatecommonproductquality

planningandcontrolplanguidelinesforsupplierstotheautomotive

industry.

ASCIIAmericanStandardCodesforInformationInterchange

ASICApplication-specificintegratedcircuit.

ATEAutomatictestequipment;automatedtestequipment.

ATMAsynchronoustransfermode

AutoShutdownAfeatureinEIA-232interfacedeviceswhichputstheICintoa

low-powershutdownmodewhennosignalispresentontheEIA-232

bus.

AutoshutdownPlusAfeatureinEIA-232interfacedeviceswhichputstheICintoa

low-powershutdownmodewhennosignalispresentonthebusorthe

transmitterinputs.

AutotransformerAnautotransformerisatransformerthatusesacommonwindingfor

boththeprimaryandsecondarywindings.Essentiallyaninductorwitha

center-tap,anautotransformerisoftenusedinpower-supply

boost-converterapplicationstoachieveahigheroutputvoltage,while

limitingthepeakflybackvoltageseenbythepowerswitch.

AWG1.Arbitrarywaveformgenerator

2.AmericanWireGauge:Ameasureofwirethickness(whichalso

dictatescross-sectionalarea,andforagivenmaterial,ampacity).

Example:24AWGwirehasanominaldiameterof0.0201inor

0.511mm.AlsocalledtheBrownandSharpeWireGauge.

Notethatsteelwireismeasuredbyadifferentgauge.AWGonlyapplies

towireusedtoconductelectricity.

BBel:Measurementofasignal'spowercomparedtoareference;also,

measurementofsoundpressure.Seethemorecommonlyusedterm,

"decibel；'or,"dB."

BackupStep-UpStep-up,switching-regulatorpowersupplywithabackupbattery

switchover.

Bandwidth1.Bandwidth(BW)isarangeoffrequencies,orinformation,thata

circuitcanhandleortherangeoffrequenciesthatasignalcontainsor

occupies.

Example:AnAMbroadcastradiochannelintheUShasabandwidthof

10kHz,meaningthatitoccupiesa10kHz-wideband,suchasthe

frequenciesfrom760kHzto770kHz.

2.Theamountofdataadigitalchannelorlinecanhandle,expressedin

bitspersecond(bps),kilobitspersecond(kbps),baud,orasimilar

measure.

BaseStationAbasestation(orbasestation)isawirelesstransceiveratafixed

location(e.g.atopatelephonepole)whichispartofawireless

communicationsnetwork,e.g.thecellphonenetwork.Typically,the

basestationconnectstoanycellphonesinitsareaandrelaysthecalls

tothewirednetwork.

Afemtobasestationisasmaller,personalbasestationwhichmight

coverahomeorbuildingandconnectviaaDSLInternetconnection.

BaselineTheelectricalsignalfromasensorwhennomeasuredvariableis

present.Oftenreferredtotheoutputatno-loadcondition.

BassBoostCircuitrythatbooststhebassresponseoftheamplifier,improvingaudio

reproduction,especiallywhenusinginexpensiveheadphones.

BatteryBackupAfeatureofmicroprocessorsupervisorycircuitsandsomepower

suppliestoswitchbetweenamainpowersourceandabattery.

BatteryFreshnessAfeatureinmicroprocessorsupervisorycircuitswhichdisconnectsa

Sealbackupbatteryfromanydown-streamcircuitryuntilVccisappliedthe

firsttime.Thiskeepsabackupbatteryfromdischarginguntilthefirst

timeaboardispluggedinandused,andthuspreservesthebatterylife.

BatteryFuelGaugeAfeatureordevicethatmeasurestheaccumulatedenergyaddedto

andremovedfromabattery,allowingaccurateestimatesofbattery

chargelevel.

BatteryMonitorAfeaturethatmonitorsthevoltageonabatteryandindicateswhenthe

batteryislow.Itisusuallyimplementedusingacomparatortocompare

thebatteryvoltagetoaspecifiedlevel.Mayalsoincludefunctionssuch

ascharging,remainingcapacityestimation,safetymonitoring,unique

ID,temperaturemeasurement,andnonvolatile(NV)parametricstorage.

BatterySwitchoverAcircuitthatswitchesbetweenthehigherofamainsupplyanda

backupbattery.

BCDBinary-codeddecimal:Representationofanumberinwhicheach

decimaldigit(0-9)isencodedinbinary,withfourbitsperdecimaldigit

BERBitErrorRate:Ameasureofthenumberoferroneousbitswhichcanbe

expectedinaspecifiednumberofbitsinaserialstream.

BERTBitErrorRate(BER)Tester:Apieceoftestequipmentwhich

determinesthebiterrorrateforadeviceundertest(DUT).

Beyond-the-Rails™Afeatureofamplifiersthatallowsinputoroutputvoltagestoexceedthe

supplyrails.

BGABallgridarray:Apackagingtechnology.

BidirectionalThedeviceaccommodatessignalstravelingeitherdirectionthougha

singlechannel.

BipolarInputsAninputwhichaccommodatessignalsbothaboveandbelowground.

BipolarJunctionABipolarJunctionTransistor,orBJT,isasolid-statedeviceinwhichthe

Transistorcurrentflowbetweentwoterminals(thecollectorandtheemitter)is

controlledbytheamountofcurrentthatflowsthroughathirdterminal

(thebase).

Contrasttotheothermaintransistortype,theFET,inwhichtheouput

currentiscontrolledbyinputvoltage(ratherthanbyinputcurrent).

BISTBuilt-inself-test.

BitBangingAtechniquewhichusesthegeneral-purposeportsofamicrocontroller

2

toemulateaserialinterfacestandard(1C,SPI,etc).

BitErrorRatioThenumberoferroneousbitsdividedbythetotalnumberofbits

transmitted,received,orprocessedoversomestipulatedperiod.

BladeServerAbladeserverisacomputersystemonamotherboard,whichincludes

processor(s),memory,anetworkconnection,andsometimesstorage.

Thebladeideaisintendedtoaddresstheneedsoflarge-scale

computingcenterstoreducespacerequirementsforapplicationservers

andlowercosts.

BlinkControlControlsthedisplaysegmentblinkrate.

BLMBalllimitingmetal

BluetoothAtechnologythatallowsvoiceanddataconnectionsbetweenawide

rangeofmobileandstationarydevicesthroughshort-rangedigital

two-wayradio.Forinstance,itspecifieshowmobilephones,Wireless

InformationDevices(WIDs),computersandPDAsinterconnectwith

eachother,withcomputers,andwithofficeorhomephones.

BLVDSBuslow-voltagedifferentialsignal

BOCBit-orientedcode

BoostConverterApowersupplythatstepsaninputvoltageup(boostsit)toahigher,

regulatedvoltage.

BootstrapOftenreferstousingtheoutputofastep-upconvertertodrivethemain

powerFETswitch,providingmoregatedrivethantheinputcansupply

alone.Alsoreferstousingaswitchedcapacitortoboostthevoltageofa

node.

BPONBroadbandpassiveopticalnetwork

BPSKBinaryphase-shiftkeying

BRDBand-ratedivisor

Break-Before-MakeBreak-Before-Make:Aswitchthatisconfiguredtobreak(open)thefirst

setofcontactsbeforeengaging(closing)thenewcontacts.This

preventsthemomentaryconnectionoftheoldandnewsignalpaths.

Appliestomechanicalsystems(e.g.thatuserelaysormanualswitches)

andtosolid-stateanalogmultiplexersandswitches.

BRIBit-rateinterface

BridgeBatteryAbatteryintendedtoprovidepowertosystemmemorywhilethemain

batteryisreplaced.

Bridge-TiedLoadUsedinaudioapplications,theload(aspeakerinthiscase)is

connectedbetweentwoaudioamplifieroutputs(it"bridges"thetwo

outputterminals).

Thiscandoublethevoltageswingatthespeaker,comparedtoa

speakerthatisconnectedtoground.Theground-tiedspeakercanhave

aswingfromzerototheamplifier'ssupplyvoltage.ABTL-driven

speakercanseetwicethisswingbecausetheamplifiercandriveeither

the+terminalofthespeakerorthe—terminal,effectivelydoublingthe

voltageswing.

Sincetwicethevoltagemeansfourtimesthepower,thisisamajor

improvement,especiallyinapplicationswherebatterysizedictatesa

lowersupplyvoltage—e.g.automotiveorhandheldapplications.

BrightnessAlthoughtheterms"brightness"andluminance"areoftenused

interchangeably,theyaredifferent.Luminanceisthelightintensity;

brightnessishowitisperceivedbythehumaneye.

BroadbandAtransmissionmediumwithenoughbandwidthtocarrymultiplevoice,

video,ordatachannelssimultaneously.

Thistechniqueisused,forexample,toprovidefiftyCATVchannelson

onecoaxialcable;ortoprovideInternetaccessovercableTV;ortoadd

DSLtoavoice-gradetelephoneline.

Acommontechniqueisfrequency-division.Eachchannelismodulated

toadifferentfrequencybandandcombinedinthetransmission

medium.Itisdemodulatedtoitsoriginalfrequencyatthereceivingend.

Channelsareseparatedbyguardbands(emptyspaces)toensurethat

eachchannelwillnotinterferewithitsneighboringchannels.

BrownoutAconditionwherethevoltagesuppliedtothesystemfallsbelowthe

specifiedoperatingrange,butaboveOV.

BSCBSC(BasicSpacingbetweenCenters)isatermthatappearsonIC

packagedrawingsinreferencetodimensionsbetweenpins.

"Basic"spacingisnominalandcanchangewithconditions.For

example,thedistancebetweentherowsofpinsonaDIP(dualinline

package)isBSCbecauseitchangeswhentheautoinsertionmachine

grabsthepart,andagainwhenthepartisinserted.TheBSC

dimension,inthiscase,isthedimensionoftheholespacingthatthe

partwillfitinto,ratherthanthedimensionsofthepartitself.

BSLFBest-straight-linefit

BTButterworth(filter)

BTSBaseTransceiverStation:Thestationarycomponentofacellphone

systemincludestransmit-receiveunitsandoneormoreantennae.The

combinedsystems(oftenincludingmultipleco-locatedsystemsand

gangeddirectionalantennae)iscalledacell-site,abasestation,ora

basetransceiverstation(BTS).

BuckA"buck"or"step-down"switch-modevoltageregulatorisoneinwhich

theoutputvoltageislowerthanitsinputvoltage.

Note:Acustomeraskedtheoriginofthetermandnooneseemsto

know!Abuckregulatorisastep-downregulator,asopposedtoboost.

Wethinkit'sanAmericanterm—inEnglanditwasalways"step-down."

Buckmeanstoresistorreduce(asin"buckthetrend"),andhencewas

usedtodenoteastep-down.Conveniently,italliterateswiththe

opposite,aboostregulator.

Buck-BoostAswitch-modevoltageregulatorinwhichoutputvoltagecanbeabove

orbelowtheinputvoltage.

BurstDimmingBurstDimmingisamethodofcontrollingthebrightnessofcoldcathode

fluorescentlamps(CCFL)byturningthelampsonandoffatarate

fasterthanthehumaneyecandetect.Theon/offrateisnominally

100Hzto300Hz.Thehighertheratioofon-timetooff-time,thebrighter

thelampswillbe.BecauseofCCFLresponsetimes,on-timetooff-time

ratiosoflessthan1%arenotpractical.

BurstMode1)Atemporaryhigh-speeddata-transfermodethatcantransferdataat

significantlyhigherratesthanwouldnormallybeachievedwithnonburst

technology.

2)Themaximumshort-termthroughputwhichadeviceiscapableof

transferringdata.

BusDatapaththatconnectstoanumberofdevices.Atypicalexampleis

thebusacomputer'scircuitboardorbackplane.Memory,processor,

andI/Odevicesmayallsharethebustosenddatafromonetoanother.

Abusactsasasharedhighwayandisinlieuofthemanydevoted

connectionsitwouldtaketohookeverydevicetoeveryotherdevice.

Oftenmisspelled"buss."

BWLSBandwidth,LargeSignal

BWSSBandwidth,SmallSignal

C1.Capacitance,capacitor;coulomb