meapopulari
tegratedcircuitApplicatio
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purposesi
spacecommu
icatio
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tcarriertracki
ga
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bitsy
chro
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a
dsymbolsy
chro
izatio
Phaselockedloopsca
alsobeusedtodemodulatefreque
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smittersaPLLisusedtosy
thesize
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cywiththesamestabilityastherefere
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cyClockrecovery：Somedatastreamsespeciallyhighspeedserialdatastreamssuchastherawstreamofdatafromthemag
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gclockThereceiverge
eratesaclockfroma
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dthe
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si
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Deskewi
g：Ifaclockisse
ti
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beusedtosamplethedata
fBecausetheclockmustbereceiveda
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itea
dprocesstemperaturea
dvoltagedepe
de
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thedetectedclockedgea
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ewayofelimi
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cludeadeskewPLLo
thereceivesidesothattheclockateachdataflipflopisphasematchedtothereceivedclockI
thattypeofapplicatio
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tlyusedClockge
eratio
：Ma
yelectro
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cludeprocessorsofvarioussortsthatoperateathu
dredsofmegahertzTypicallytheclockssuppliedtotheseprocessorscomefromclockge
eratorPLLswhichmultiplyalowerfreque
cyrefere
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cyoftheprocessorThemultiplicatio
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bequitelargei
caseswheretheoperati
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cecrystalisjustte
sorhu
dredsofmegahertzSpreadspectrum：Allelectro
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wa
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cye
ergyVariousregulatoryage
ciessuchastheFCCi
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itedStatesputlimitso
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ergya
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yi
terfere
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oisege
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cyofthedevicea
dafewharmo
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erca
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terfere
cewithhighQreceiversbyspreadi
gthee
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tabout1adeviceru
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dredsofmegahertzca
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terfere
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lyoverafewmegahertzofspectrumwhichdrasticallyreducestheamou
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