adc dac loopback linearity
TRANSCRIPT
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IEEETRANSACTIONSONVERYLARGESCALEINTEGRATION(VLSI)SYSTEMS,VOL.19,NO.10,OCTOBER2011 1765
ADC/DACLoop!"#L$%&!'$T&*$%+DAC OpO--*&$%+!%S"!$%+
!%L%!%+,StudentMember,IEEE,!% 3$%L!%+!%+,Member,IEEE
AbstractLoopback testing is a powerful technique for testingthe analog-to-digital converter (ADC) and digital-to-analog con-verter (DAC) pair embedded in a mixed-signal sstem-on-chip(!oC)" #hile attractive$ its performance is generall limitedb the achievable test resolution and the potential faultmasking problem" %n this work$ a loopback linearit testingtechnique for an ADC&DAC pair is presented' the ke idea is toraisetheeffec- tiveADCandDACresolutionbscaling theDACoutput" irst$ duringADCtesting$wescaledowntheDACoutputtoachievethe requiredteststimulusresolutionandadusttheDACoutput offset to cover the ADC full-scale range" *hen$ for DACtesting$ we raise the effective ADC resolution b scaling up theDAC output" +oth simulation and measurement results arepresentedtovalidatethe proposedtechnique"Index TermsAnalog-to-digital converter (ADC)&digital-to-
analog (DAC) testing$ design-for-test (Df*)$ loopback testing$mixed-signaltesting$segmentedcurrent-steeringDAC"
I. INTROD4CTION
#IT & '!p$ &o$o% o- *&$"o%"o'&"%oo +$&*, $ $* %o8 "oo% p'!"$"& o$%&+'!& &
$&*$+%! "$'"$* 8$ o&' $+$! "o'&* $%o ! *$%+&**&o%"$p (SoC) o' **&$%p!"#!+& (S$:) ;2
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p!) *o ! & "!% &* &!" o&' &"o&* !
p'o$*$%+ *o$o% o !o!$" &* &@$p&% (ATE) "o*
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1766 IEEETRANSACTIONSONVERYLARGESCALEINTEGRATION(VLSI)SYSTEMS,VOL.19,NO.10,OCTOBER2011
&DACop.T&%, &ADC $*$$& o &*o%&"''&%
*o'"& $% & SCSDAC !! $&. H'o & '&**, & DAC
$%p/op (I/O) '!%*-&' "'& "!%& "o%*'"& !**$%+
!&"''&%*!$o%$*$&!.
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&*$%+&ooo+!'&!*-oo8*.
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&DACop.Ho'SCSDAC,$*"!%&&!*$'&!$&
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&*&o-o--*&o!+&*%&&%o&&'!""'!&.
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8& '$&- $%'o"& & $%&!'$ *p&"$-$"!$o%* o- !!
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$*'!& &p'o po*& &"%$@& $% &!$. I% S&"$o% V, &
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'&*p&"$&.H$%!,8&"o% "&$*p!p&'$%S&"$o%VIII.
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LSB, 8$" "o''&*po%* o & !&'!+& o!+& $%"'&&% o-
&DAC, $*&-$%&!*
(>)
8&'& $*&DAC'&*o$o%.DNL!%INLo-&DAC"!%
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II. LINEARITYOHDATACONVERTERS
I% $* 8o'#, 8& *& &&%po$% $%&!* & '&-&'&%"& $%&
!%"op&&&%po$%DNL!%INL;17
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o!op"''&% $*$'&"&o&o!'&*$*&'
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VI. SIM4LATIONRES4LTS
& -$'*p&'-o' %&'$"! *$!$o%* o !$!& &p'o
po*& &"%$@&. T& HSR o- & DAC op !% &
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*$+%&!%o%&7.D'$%+&*$%+,o*"!$%+-!"o'*
!% !'&*&o60.
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*'!&&!$!"$&!&&*!""'!".
T&ADC$*-$'*&*&!%$&!16$DAC8$&'!$
$o%!$%&!'$*o+'!&*$%+.T&&!*'&INL!%DNL!'&
*o8% $% & &-!% *$& (LS)po* o- H$+. 10 &p&!#
DNL !% INL !'& 2.71 !% 2.2> LSB, '&*p&"$&.No& !
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p'opo*& ADC oop!"# &*$%+ &"%$@& $* !pp$&. T&
&*$!& INL !% DNL !'& *o8% $% & '$+!% *$&
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&''o'* !'& *o8% $% H$+. 11 & &''o'* !'& ! &** !% 0.1
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!&'!+&o!#$%+o'&*!p&*o8&&', $*p'oo%+*
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T& LS po* o- & -$+'& !'& & !"! DAC
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!""'!", 8& *8&&p &$' !&* -'o 1 o 60, !% '&"o'
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"oo*$%+ !pp'op'$!& *"!$%+ -!"o'*, & !'$!$o%* $% &+!$%
"o%'o '&*$*o'* o% "!*& %&+$+$& &--&" o & &*!""'!" $* &o%*'!&* & 'o*%&** o- &p'opo*&
&"%$@&.
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&%o%$%&!'$o-ADC!%DAC.To!**&**$*$p!",8&*&
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177> IEEETRANSACTIONSONVERYLARGESCALEINTEGRATION(VLSI)SYSTEMS,VOL.19,NO.10,OCTOBER2011
H$+.2>. DAC&*$%+&''o'*.
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T$*p!p&'p'&*&%* ! *$p& & &--$"$&% *!$" oop!"#
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p'o$*$%+ *o$o% o SoC* 8$ o ADC !% DAC.
Ep&'$&%! '&** !*& o% "o&'"$! IC* *o8 !&'
$+ &* !""'!" "!% & !"$&& &&% $% &p'&*&%"& o-
%o$*&.
REHERENCES
;1.
;2,%o.=,pp.11?1199,3%.2005.
;1=