學生學生 :: 李國彰李國彰指導教授指導教授 :: 賴永齡老師賴永齡老師

A 1.5V 2.4GHz CMOS Mixer with A 1.5V 2.4GHz CMOS Mixer with high linearityhigh linearity( The 2004 IEEE Asia-Pacific ( The 2004 IEEE Asia-Pacific Conference on Circuits Conference on Circuits and Systems , December 6-9 , 2004 )and Systems , December 6-9 , 2004 )

OutlineOutline AbstractAbstract IntroductionIntroduction Design methodology of mixersDesign methodology of mixers Simulation ResultsSimulation Results ConclusionConclusion ReferenceReference

AbstractAbstract

High linearityHigh linearity ISM band ISM band Modified Class AB transconducModified Class AB transconduc

tortor Common mode feedback circuCommon mode feedback circu

itryitry

IntroductionIntroduction

GaAs , Bipolar >> high cost , compGaAs , Bipolar >> high cost , complexitylexity

CMOS CMOS Down-convertDown-convert Up-convertUp-convert IIP3 , P IIP3 , P 1dB1dB

IntroductionIntroduction

SFDR ( spurious-free dynamic SFDR ( spurious-free dynamic range )range )

Design methodology Design methodology of mixersof mixers

Source degenerationSource degeneration CMOS gCMOS gmm Cell Cell Modified Class AB transconductorModified Class AB transconductor C1 C2->DC-blockingC1 C2->DC-blocking M5-M8 ->promote isolationM5-M8 ->promote isolation

Design methodology Design methodology of mixersof mixers

M11-M14 -> switchM11-M14 -> switch M15 M16 R1 R2 ->load stageM15 M16 R1 R2 ->load stage M17-M21->CMFB circuitM17-M21->CMFB circuit

->stable dc level->stable dc level

->conversion gain ->conversion gain

Simulation ResultsSimulation Results RF->2.4GHz RF->2.4GHz LO->2.3GHzLO->2.3GHz IF->100MHzIF->100MHz 3.73mA from a 1.5V3.73mA from a 1.5V Tsmc 0.18Tsmc 0.18μm Mixed signal CMOS RF μm Mixed signal CMOS RF

modelmodel

ConclusionConclusion Transconductor -> linearity of Transconductor -> linearity of

a mixera mixer CMFB with the modified Class CMFB with the modified Class

AB transconductor->improve IIAB transconductor->improve IIP3 , conversion gainP3 , conversion gain

ReferenceReference