User`s guide

Rev. 1.10 90 November 14, 2014 Rev. 1.10 91 November 14, 2014
HT66FW2230
Wireless Charger A/D Flash 8-Bit MCU
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
 
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 
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
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
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
 



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A/D Conversion Timing
Programming Considerations
DuringmicrocontrolleroperationswheretheA/Dconverterisnotbeingused,theA/Dinternal
circuitrycanbeswitchedofftoreducepowerconsumption,bysettingbitADOFFhighinthe
ADCR0register.Whenthishappens,theinternalA/Dconvertercircuitswillnotconsumepower
irrespectiveofwhatanalogvoltageisappliedtotheirinputlines.IftheA/Dconverterinputlinesare
usedasnormalI/Os,thencaremustbetakenasiftheinputvoltageisnotatavalidlogiclevel,then
thismayleadtosomeincreaseinpowerconsumption.
A/D Transfer Function
Asthedevicecontainsa12-bitA/Dconverter,itsfull-scaleconverteddigitisedvalueisequalto
FFFH.Sincethefull-scaleanaloginputvalueisequaltotheV
DD
orV
REF
voltage,thisgivesasingle
bitanaloginputvalueofV
DD
orV
REF
dividedby4096.
1LSB=(V
DD
orV
REF
)/4096
TheA/DConverterinputvoltagevaluecanbecalculatedusingthefollowingequation:
A/Dinputvoltage=A/Doutputdigitalvalue×(V
DD
orV
REF
)/4096
Thediagramshowstheidealtransferfunctionbetweentheanaloginputvalueandthedigitised
outputvaluefortheA/Dconverter.Exceptforthedigitisedzerovalue,thesubsequentdigitised
valueswillchangeatapoint0.5LSBbelowwheretheywouldchangewithouttheoffset,andthe
lastfullscaledigitisedvaluewillchangeatapoint1.5LSBbelowtheV
DD
orV
REF
level.

 
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

 
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

   
 
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
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
Ideal A/D Transfer Function