HT66F60 datasheet(56/298 Pages) HOLTEK

56 / 298 page

Rev. 1.90

�e��a�� 18� �01�

Rev. 1.90

�e��a�� 18� �01�

HT66F20/HT66F30/HT66F40/HT66F50/HT66F60

HT66FU30/HT66FU40/HT66FU50/HT66FU60

Enhanced A/D Flash Type 8-Bit MCU with EEPROM

HT66F20/HT66F30/HT66F40/HT66F50/HT66F60

HT66FU30/HT66FU40/HT66FU50/HT66FU60

Enhanced A/D Flash Type 8-Bit MCU with EEPROM

LXT Oscillator Low Power Function

TheLXToscillatorcanfunctioninoneoftwomodes,theQuickStartModeandtheLowPower

Mode.ThemodeselectionisexecutedusingtheLXTLPbitintheTBCregister.

LXTLP Bit

LXT Mode

Q�ick Sta�t

Low-powe�

AfterpowerontheLXTLPbitwillbeautomaticallyclearedtozeroensuringthattheLXToscillator

isintheQuickStartoperatingmode.IntheQuickStartModetheLXToscillatorwillpowerup

andstabilisequickly.However,aftertheLXToscillatorhasfullypoweredupitcanbeplaced

intotheLow-powermodebysettingtheLXTLPbithigh.Theoscillatorwillcontinuetorunbut

withreducedcurrentconsumption,asthehighercurrentconsumptionisonlyrequiredduringthe

LXToscillatorstart-up.Inpowersensitiveapplications,suchasbatteryapplications,wherepower

consumptionmustbekepttoaminimum,itisthereforerecommendedthattheapplicationprogram

setstheLXTLPbithighabout2secondsafterpower-on.

Itshouldbenotedthat,nomatterwhatconditiontheLXTLPbitissetto,theLXToscillatorwill

alwaysfunctionnormally,theonlydifferenceisthatitwilltakemoretimetostartupifinthe

Low-powermode.

Internal Low Speed Oscillator – LIRC

TheInternal32kHzSystemOscillatorisoneofthelowfrequencyoscillatorchoices,whichis

selectedviaconfigurationoption.ItisafullyintegratedRCoscillatorwithatypicalfrequencyof

32kHzat5V,requiringnoexternalcomponentsforitsimplementation.Devicetrimmingduring

themanufacturingprocessandtheinclusionofinternalfrequencycompensationcircuitsareused

toensurethattheinfluenceofthepowersupplyvoltage,temperatureandprocessvariationsonthe

oscillationfrequencyareminimised.Asaresult,atapowersupplyof5Vandatatemperatureof

25˚Cdegrees,thefixedoscillationfrequencyof32kHzwillhaveatolerancewithin10%.

Supplementary Oscillators

Thelowspeedoscillators,inadditiontoprovidingasystemclocksourcearealsousedtoprovide

aclocksourcetotwootherdevicefunctions.ThesearetheWatchdogTimerandtheTimeBase

Interrupts.

HT66F60 Datasheet(PDF) 56 Page - Holtek Semiconductor Inc