Holtek HT66F30 - Fast Wake-�P

Rev. 2.50 60 June 22, 2017 Rev. 2.50 61 June 22, 2017
HT66F20/HT66F30/HT66F40/HT66F50/HT66F60
HT66FU30/HT66FU40/HT66FU50/HT66FU60
A/D Flash MCU with EEPROM
HT66F20/HT66F30/HT66F40/HT66F50/HT66F60
HT66FU30/HT66FU40/HT66FU50/HT66FU60
A/D Flash MCU with EEPROM
Fast Wake-up
TominimisepowerconsumptionthedevicecanentertheSLEEPorIDLE0Mode,wherethesystem
clocksourcetothedevicewillbestopped.Howeverwhenthedeviceiswokenupagain,itcantake
aconsiderabletimefortheoriginalsystemoscillatortorestart,stabiliseandallownormaloperation
toresume.ToensurethedeviceisupandrunningasfastaspossibleaFastWake-upfunctionis
provided,whichallowsf
SUB
,namelyeithertheLXTorLIRCoscillator,toactasatemporaryclock
torstdrivethesystemuntiltheoriginalsystemoscillatorhasstabilised.Astheclocksourcefor
theFastWake-upfunctionisf
SUB
,theFastWake-upfunctionisonlyavailableintheSLEEP1and
IDLE0modes.WhenthedeviceiswokenupfromtheSLEEP0mode,theFastWake-upfunctionhas
noeffectbecausethef
SUB
clockisstopped.TheFastWake-upenable/disablefunctioniscontrolled
usingtheFSTENbitintheSMODregister.
IftheHXToscillatorisselectedastheNORMALModesystemclock,andiftheFastWake-up
functionisenabled,thenitwilltakeonetotwot
SUB
clockcyclesoftheLIRCorLXToscillatorfor
thesystemtowake-up.Thesystemwilltheninitiallyrununderthef
SUB
clocksourceuntil1024
HXTclockcycleshaveelapsed,atwhichpointtheHTOagwillswitchhighandthesystemwill
switchovertooperatingfromtheHXToscillator.
IftheERCorHIRCoscillatorsorLIRCoscillatorisusedasthesystemoscillatorthenitwilltake
15~16clockcyclesoftheERCorHIRCor1~2cyclesoftheLIRCtowakeupthesystemfromthe
SLEEPorIDLE0Mode.TheFastWake-upbit,FSTENwillhavenoeffectinthesecases.
System
Oscillator
FSTEN
Bit
Wake-up Time
(SLEEP0 Mode)
Wake-up Time
(SLEEP1 Mode)
Wake-up Time
(IDLE0 Mode)
Wake-up Time
(IDLE1 Mode)
HXT
0
1024 HXT cycles 1024 HXT cycles 1~2 HXT cycles
1 1024 HXT cycles
1~2 f
SUB
cycles
(System runs with f
SUB
rst for 1024 HXT cycles and
then switches over to run with the HXT clock )
1~2 HXT cycles
ERC x 15~16 ERC cycles 15~16 ERC cycles 1~2 ERC cycles
HIRC x 15~16 HIRC cycles 15~16 HIRC cycles 1~2 HIRC cycles
LIRC x 1~2 LIRC cycles 1~2 LIRC cycles 1~2 LIRC cycles
LXT x 1024 LXT cycles 1024 LXT cycles 1~2 LXT cycles
Wake-up Times
NotethatiftheWatchdogTimerisdisabled,whichmeansthattheLXTandLIRCareallbothoff,
thentherewillbenoFastWake-upfunctionavailablewhenthedevicewakes-upfromtheSLEEP0
Mode.