HT45F5R datasheet(38/138 Pages) HOLTEK

38 / 138 page

Rev. 1.10

�8

De�e��e� 1�� 01�

Rev. 1.10

�9

De�e��e� 1�� 01�

HT45F5R

Charger ASSP Flash MCU

HT45F5R

Charger ASSP Flash MCU

Internal RC Oscillator – HIRC

TheinternalRCoscillatorisafullyintegratedsystemoscillatorrequiringnoexternalcomponents.

The internal RC oscillator has a fixed frequency of 8MHz. Device trimming during the

manufacturingprocessandtheinclusionofinternalfrequencycompensationcircuitsareusedto

ensurethattheinfluenceofthepowersupplyvoltage,temperatureandprocessvariationsonthe

oscillationfrequencyareminimised.Asaresult,atapowersupplyof5Vandattemperatureof25°C

degrees,thefixedoscillationfrequencyoftheHIRCwillhaveatolerancewithin2%.

Internal 32kHz Oscillator – LIRC

Theinternal32kHzSystemOscillatoristhelowfrequencyoscillator.Itisafullyintegrated

RCoscillatorwithatypicalfrequencyof32kHzat5V,requiringnoexternalcomponentsforits

implementation.Devicetrimmingduringthemanufacturingprocessandtheinclusionofinternal

frequencycompensationcircuitsareusedtoensurethattheinfluenceofthepowersupplyvoltage,

temperatureandprocessvariationsontheoscillationfrequencyareminimised.

Supplementary Oscillator

Thelowspeedoscillator,inadditiontoprovidingasystemclocksourceisalsousedtoprovide

aclocksourcetotwootherdevicefunctions.ThesearetheWatchdogTimerandtheTimeBase

Interrupts.

Operating Modes and System Clocks

Presentdayapplicationsrequirethattheirmicrocontrollershavehighperformancebutoftenstill

demandthattheyconsumeaslittlepoweraspossible,conflictingrequirementsthatareespecially

trueinbatterypoweredportableapplications.Thefastclocksrequiredforhighperformancewill

bytheirnatureincreasecurrentconsumptionandofcoursevice-versa,lowerspeedclocksreduce

currentconsumption.AsHoltekhasprovidedthedevicewithbothhighandlowspeedclocksources

andthemeanstoswitchbetweenthemdynamically,theusercanoptimisetheoperationoftheir

microcontrollertoachievethebestperformance/powerratio.

System Clocks

ThisdevicehastwodifferentclocksourcesforboththeCPUandperipheralfunctionoperation.

Byprovidingtheuserwithclockselectionsusingregisterprogramming,aclocksystemcanbe

configuredtoobtainmaximumapplicationperformance.

Themainsystemclock,cancomefromeitherahighfrequency,fH,oralowfrequency,fSUB,and

isselectedusingtheCKS2~CKS0bitsintheSCCregister.Thehighspeedsystemclockcanbe

sourcedfromHIRCoscillator.Thelowspeedsystemclocksourcecanbesourcedfromtheinternal

clockfSUB.Theotherchoice,whichisadividedversionofthehighspeedsystemoscillatorhasa

rangeoffH/2~fH/64.

Thereisoneadditionalinternalclockfortheperipheralcircuits,theTimeBaseclock,fTBC.fTBCis

sourcedfromtheLIRCoscillator.ThefTBCclockisusedasasourcefortheTimeBaseinterrupt

functionsandfortheTM.

HT45F5R Datasheet(PDF) 38 Page - Holtek Semiconductor Inc

HT45F5R Datasheet(HTML) 38 Page - Holtek Semiconductor Inc

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL