 |
Electronic Components Datasheet Search |
|
|
Electronic Components Datasheet Search |
|
HT45R2K-C Datasheet(PDF) 29 Page - Holtek Semiconductor Inc |
|
||||||||||||||||||||||||||||||
HT45R2K-C Datasheet(HTML) 29 Page - Holtek Semiconductor Inc |
|
|
29 / 105 page  Rev. 1.40 �8 �a��� 1�� �01� Rev. 1.40 �9 �a��� 1�� �01� HT45R2K-C/-B/-A Dual Slope 16K/8K/4K ASSP MCU for Body Fat Scale HT45R2K-C/-B/-A Dual Slope 16K/8K/4K ASSP MCU for Body Fat Scale Internal RC Oscillator – HIRC TheinternalRCoscillatorisafullyintegratedsystemoscillatorrequiringnoexternalcomponents. TheinternalRCoscillatorhasthreefixedfrequenciesofeither4MHz,8MHzor12MHz.Device trimmingduringthemanufacturingprocessandtheinclusionofinternalfrequencycompensation circuitsareusedtoensurethattheinfluenceofthepowersupplyvoltage,temperatureandprocess variationsontheoscillationfrequencyareminimised.Asaresult,atapowersupplyofeither3Vor 5Vandatatemperatureof25℃degrees,thefixedoscillationfrequencyof4MHz,8MHzor12MHz willhaveatolerancewithin2%.Notethatifthisinternalsystemclockoptionisselected,asit requiresnoexternalpinsforitsoperation,I/OpinsPA5andPA6arefreeforuseasnormalI/Opins. External 32.768kHz Crystal Oscillator – LXT TheExternal32.768kHzCrystalOscillatorisoneofthelowfrequencyoscillatorchoices,which isselectedviaaconfigurationoption.Thisclocksourcehasafixedfrequencyof32.768kHzand requiresa32.768kHzcrystaltobeconnectedbetweenpinsXT1andXT2.Theexternalresistorand capacitorcomponentsconnectedtothe32.768kHzcrystalarenecessarytoprovideoscillation.For applicationswhereprecisefrequenciesareessential,thesecomponentsmayberequiredtoprovide frequencycompensationduetodifferentcrystalmanufacturingtolerances.Duringpower-upthereis atimedelayassociatedwiththeLXToscillatorwaitingforittostart-up. WhenthemicrocontrollerentersthePowerdownMode,thesystemclockisswitchedofftostop microcontrolleractivityandtoconservepower.However,inmanymicrocontrollerapplicationsit maybenecessarytokeeptheinternaltimersoperationalevenwhenthemicrocontrollerisinthe PowerdownMode.Todothis,anotherclock,independentofthesystemclock,mustbeprovided. TheexactvaluesofC1andC2shouldbeselectedinconsultationwiththecrystalorresonator manufacturer’sspecification.Theexternalparallelfeedbackresistor,Rp,isrequired. Foroscillatorstabilityandtominimisetheeffectsofnoiseandcrosstalk,itisimportanttoensure thatthecrystalandanyassociatedresistorsandcapacitorsalongwithinterconnectinglinesareall locatedasclosetotheMCUaspossible. To i nt er nal ci rc ui ts Ho lt ek MC U C1 C2 Rp No te :1 . RT C OS C: w it hout bu ild -i n RC 2. R p , C 1 and C 2 ar e re qui r ed. 3. A lt hough not s how n pi ns h av e a par as it ic c apac it an ce o f a r ound 7pF . 32768H z XT 1 XT 2 Ex te rn a l 32. 7 68kH z Cr ys ta l O sci ll at or - L XT LXT Oscillator C1 and C2 Values Crystal Frequency C1 C2 3�768Hz 8pF 10pF Note: 1. C1 and C� values a�e fo� guidan�e only. �. RP = 5M~10MΩ is recommended. 32768Hz Crystal Recommended Capacitor Values |
Similar Part No. - HT45R2K-C_15 |
|
Similar Description - HT45R2K-C_15 |
|
|
Link URL |
| Privacy Policy |
| ALLDATASHEET.NET |
| Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Contact us | Privacy Policy | 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
