HT69F360 datasheet(63/235 Pages) HOLTEK

63 / 235 page

Rev. 1.30

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HT69F340/HT69F350/HT69F360

TinyPowerTM I/O Flash MCU with LCD & EEPROM

HT69F340/HT69F350/HT69F360

TinyPowerTM I/O Flash MCU with LCD & EEPROM

LXT Oscillator Low Power Function

TheLXToscillatorcanfunctioninoneoftwomodes,theSpeed-UpModeandtheLow-Power

Mode.ThemodeselectionisexecutedusingtheLXTSPbitintheLXTCregister

LXTSP Bit

LXT Operating Mode

Low Powe�

Speed up

WhentheLXTSPbitissettohigh,theLXTSpeedUpModewillbeenabled.IntheSpeed-Up

ModetheLXToscillatorwillpowerupandstabilisequickly.However,aftertheLXToscillatorhas

fullypoweredup,itcanbeplacedintotheLow-PowerModebyclearingtheLXTSPbittozeroand

theoscillatorwillcontinuetorunbutwithreducedcurrentconsumption.Itisimportanttonotethat

theLXToperatingmodeswitchingmustbeproperlycontrolledbeforetheLXToscillatorclockis

selectedasthesystemclocksource.OncetheLXToscillatorclockisselectedasthesystemclock

sourceusingtheCKSbitfieldandFSSbitintheSCCregister,theLXToscillatoroperatingmode

cannotbechanged.

ItshouldbenotethatnomatterwhatconditiontheLXTSPissetto,theLXToscillatorwillalways

functionnormally.TheonlydifferenceisthatitwilltakemoretimetostartupifintheLowPower

Mode.

Internal 32kHz Oscillator – LIRC

TheInternal32kHzSystemOscillatorisoneofthelowfrequencyoscillatorchoices,whichis

selectedviaFSSbit.ItisafullyintegratedRCoscillatorwithatypicalfrequencyof32kHzat5V,

requiringnoexternalcomponentsforitsimplementation.Devicetrimmingduringthemanufacturing

processandtheinclusionofinternalfrequencycompensationcircuitsareusedtoensurethat

theinfluenceofthepowersupplyvoltage,temperatureandprocessvariationsontheoscillation

frequencyareminimised.Asaresult,atapowersupplyof5Vandatatemperatureof25°Cdegrees,

thefixedoscillationfrequencyof32kHzwillhaveatolerancewithin10%.

Supplementary Oscillator

Thelowspeedoscillators,inadditiontoprovidingasystemclocksourcearealsousedtoprovide

aclocksourcetootherdevicefunctions.ThesearetheWatchdogTimer,LCDdriverandtheTime

BaseInterrupts.

HT69F360 데이터시트(PDF) 63 Page - Holtek Semiconductor Inc