 |
Electronic Components Datasheet Search |
|
|
Electronic Components Datasheet Search |
|
HT45F0027 Datasheet(PDF) 39 Page - Holtek Semiconductor Inc |
|
|
|||||||||||||||||||||||||||||
HT45F0027 Datasheet(HTML) 39 Page - Holtek Semiconductor Inc |
|
|
39 / 112 page  Rev. 1.20 38 �an�a�� 21� 201� Rev. 1.20 39 �an�a�� 21� 201� HT45F0027 PIR 8-Bit Flash MCU HT45F0027 PIR 8-Bit Flash MCU Standby Current Considerations AsthemainreasonforenteringtheSLEEPorIDLEModeistokeepthecurrentconsumptionofthe devicetoaslowavalueaspossible,perhapsonlyintheorderofseveralmicro-ampsexceptinthe IDLE1Mode,thereareotherconsiderationswhichmustalsobetakenintoaccountbythecircuit designerifthepowerconsumptionistobeminimised.SpecialattentionmustbemadetotheI/Opins onthedevice.Allhigh-impedanceinputpinsmustbeconnectedtoeitherafixedhighorlowlevelas anyfloatinginputpinscouldcreateinternaloscillationsandresultinincreasedcurrentconsumption. Thisalsoappliestothedevicewhichhasdifferentpackagetypes,astheremaybeunbondedpins. Thesemusteitherbesetupasoutputsorifsetupasinputsmusthavepull-highresistorsconnected. Caremustalsobetakenwiththeloads,whichareconnectedtoI/Opins,whicharesetupasoutputs. Theseshouldbeplacedinaconditioninwhichminimumcurrentisdrawnorconnectedonlyto externalcircuitsthatdonotdrawcurrent,suchasotherCMOSinputs. IntheIDLE1Modethesystemoscillatorison,ifthesystemoscillatorisfromthehighspeedsystem oscillator,theadditionalstandbycurrentwillalsobeperhapsintheorderofseveralhundredmicro- amps. Wake-up AfterthesystementerstheSLEEPorIDLEMode,itcanbewokenupfromoneofvarioussources listedasfollows: • Anexternalreset • AnexternalfallingedgeonPortA • Asysteminterrupt • AWDToverflow Whenthedeviceexecutesthe"HALT"instruction,thePDFflagwillbesetto1.ThePDFflagwill beclearedto0ifthedeviceexperiencesasystempower-uporexecutestheclearWatchdogTimer instruction.IfthesystemiswokenupbyaWDToverflow,aWatchdogTimerresetwillbeinitiated andtheTOflagwillbesetto1.TheTOflagissetifaWDTtime-outoccursandcausesawake-up thatonlyresetstheProgramCounterandStackPointer,otherflagsremainintheiroriginalstatus. EachpinonPortAcanbesetupusingthePAWUregistertopermitanegativetransitiononthepin towake-upthesystem.WhenaPortApinwake-upoccurs,theprogramwillresumeexecutionat theinstructionfollowingthe"HALT"instruction.Ifthesystemiswokenupbyaninterrupt,then twopossiblesituationsmayoccur.Thefirstiswheretherelatedinterruptisdisabledortheinterrupt isenabledbutthestackisfull,inwhichcasetheprogramwillresumeexecutionattheinstruction followingthe"HALT"instruction.Inthissituation,theinterruptwhichwoke-upthedevicewillnot beimmediatelyserviced,butwillratherbeservicedlaterwhentherelatedinterruptisfinallyenabled orwhenastacklevelbecomesfree.Theothersituationiswheretherelatedinterruptisenabledand thestackisnotfull,inwhichcasetheregularinterruptresponsetakesplace.Ifaninterruptrequest flagissethighbeforeenteringtheSLEEPorIDLEMode,thewake-upfunctionoftherelated interruptwillbedisabled. |
|
Link URL |
| Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Contact us | Privacy Policy | Link to Datasheet | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
| Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
|
Family Site : ic2ic.com |
icmetro.com |
English ▼
English
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
Indian
Mexican
British
New Zealand
