赵夕彬(中国电子科技集团公司第十三研究所,石家庄050051):针对固态脉冲功率放大器存在脉冲波形顶降问题,从功率放大器的基本原理构成出发,对引起脉冲顶降的三个主要方面进行了分析讨论:GaAs晶体管脉冲调制开关电路、Si微波脉冲功率晶体管自身顶降以及功率晶体管的匹配电路,通过理论推导指出了脉冲顶降产生的原因,结合设计制作固态功率放大器时常出现的脉冲顶降问题,提出了解决办法及改善途径,并通过实验进行了验证,使脉冲顶降得到了改善。:脉冲功率放大器;微波脉冲晶体管;调制电路;脉冲波形顶降:TN722.75 :A :1003-353X(2009)04-0381-04ResearchofPulseWaveformDropofSolid-StatePulsePowerAmplifierZhaoXibin(The13thResearchInstitute,CETC,Shijiazhuang050051,China)Abstract:Aimingattheproblemofpulsewaveformdropexistedinsolid-statepulsepoweramplifier,threemainreasonswereanalyzed,pulsemodulatedswitchcircuitofGaAstransistor,theinherentdropofSimicrowavepulsetransistorandthematchingcircuitofpowertransistor.Accordingtothetheoreticdeductionandtheproblemsofpulsewaveformdropencounteredduringsolidstatepoweramplifierdesign,themethodforimprovingwasvalidated,andtheperformancewasenhancedusingthemethod.Keywords:plusepower-amplifier;microwavepulsetransistor;modulatedcircuit;pulsewaveformdropEEACC:1220;2560J0 引言[1],、、、,,,、。、、、、()。,;,,。:、Si、。,5%0.3dB。,GaAs、Si。1 固态脉冲功率放大器基本工作原理1,AGaAs,,GaAs,(,)。(FET),。,SiDesignandDevelopmentofICApril 2009SemiconductorTechnologyVol.34No.4 381 ,SiC,。(1)。1 Fig.1 Schematicdiagramofpulsepoweramplifier①,,,,、;②,,;③FET,Si,。2 脉冲波形顶部降落的定义2,d,dB,%,d=(E1-E2)/E1(1)2 Fig.2 Definitionofwaveformparametersanddrop,:tr,tf,D,T。3 脉冲顶降形成与分析,,,,、,、,,;,、、;,,,50Ψ,,。GaAsAAB,,GaAs。SiC,。,,Si。3.1 FET,,,,;CRL,3,,FETRL。3 Fig.3 Equivalentcircuitofpulsemodulation,,,。,S,RC,C;,S,C,,C赵夕彬:固态脉冲功率放大器脉冲波形顶降的研究382 半导体技术第34卷第4期2009年4月,。C,,,,,,,,。,,。,S,RL,0,U(t)=-1C∫t∞i(ζ)dζ=-1C∫tt0i(ζ)dζt≥t0(2)C,ΔU(t)=U(t0)-U(t)=-1CIp(t-t0)=1CIpτ(3)VCC,d=E1-E2E1=VCC-U(t)VCC=ΔU(t)VCC=Ip·τC·VCC(4):Ip;τ。,,。,“∝”“0”,,。,RLRC,,;。3.2 Si,Si,,[2]GP=k(fmaxf)2(5) fmax=(fT8πrbcc)1/2(6)(5)、(6)GP=k=fT8πf2rbcc=k′fTπf2rbcc K′=k8(7)fT≈2π[x2ie2DPOβ0+RE(CTC+CTE)+w2bnDnb+xd2vs+rSCcTC]-1(8) Dμ=kTq(9) μ=qmx1AT3/2+BNiT3/2(10) (9)、(10) D=kmx1AT1/2+BNiT5/2(11)Ni1018cm-3,μ,(8)、(9)D,(6)fT,GP,v=μE,μ,,fT,(5)GP。J=nqμE,μ,,,。σ=nqμ,μ,,,((8)RE,rsc),fT,GP。,Si,,,,,,,,Si—,。,[3],,,,,。,,。4.3 ,,50Ψ,50Ψ赵夕彬:固态脉冲功率放大器脉冲波形顶降的研究April 2009SemiconductorTechnologyVol.34No.4 383 ,。,,,,,,,,—。5 实践中脉冲顶降问题解决途径及实验结果,。。,,(4、5、6、7)。4 Fig.4 Deficientofstoredcapacitanceandmismatching5 Fig.5 Enlargestoredcapacitanceandoptimal6 Fig.6 Pulsemodulatedwaveformwithdisfigurement7 RCFig.7 WaveformafteraddingRC①,,,,,;②,“0”“∝”,;③,RLRC,,,;④,,,,。,。(392)赵夕彬:固态脉冲功率放大器脉冲波形顶降的研究384 半导体技术第34卷第4期2009年4月、、,,5R8,50μs,1500Ψ2mA,930/s。8 Fig.8 Outputvoltageofthetestelectrode6 结论16、,,。16,2μA~2mA1024,ELIdle,。,,,。:[1]NIPARKOJK,KIRKKI,MELLONNK,etal.Cochlearimplants-principlesandpractices[M].Philadelphia:USALippincottWilliams&Wilkins,2000:1-41.[2]SIMMONSFB,EPLEYJM,LUMMISRC,etal.Electricalstimulationoftheauditorynerveinman[J].Science,1965,148(3666)84:104-106.[3]ROBERTLW.Reviewofcurrentstatusofcochlearprostheses[J].IEEETransonBiomedicalEngineering,1982,29(4):233-238.[4]NAJAFIK.Recentprogressinmicromachiningtechnologyandapplicationinimplantablebiomedicalsystems[C]∥ProcoftheSixthIntSymponMicromachineandHumanScience.Nagoya,Japan,1995:11-20.[5]LOIZOUPC.Mimickingthehumanear[J].IEEESignalProcessingMagazine,1998,15(5):101-130.[6]ZHANGC,WANGZH,LIDM,etal.Amultimodeandmulti-channelcochlearimplant[C]∥ProcofIEEEICSP'04.Beijing,China,2004:2237-2240.[7].[D].:,2000:1-40.[8]..CMOS[M].:,2003:309-327.(:2008-11-07):(1982—),,,,;(1972—),,,,、。(384)6 结语,,,,。,,,。、,,、、,,,。:[1],.[M].:,1995:23-43.[2].[M].:,1980:186.[3],,,.[J].,2003,24(2):209-213.(:2008-12-16):(1970—),,,,,、、,。王志军 等:人工耳蜗专用植入刺激芯片设计392 半导体技术第34卷第4期2009年4月