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9(1)191DonaldKennedy()EMCPCBPCB(EMC)ICICICPCBPCBPCBPCBPCB,PCB50MHzPCBPCBPCBEMCEMCPCBEMC/EMIEMIEMIPCBEMI95%EMCregulationRFIESDPowerDisturbanceSelf-compatibilityEMCEMC9(1)2(1)(2)(3)PCBPCBPCB(1)(2)(3)I/OPCB(1)---(2)---AC/(3)AC---(4)/(1)(2)(3)(4)(1)(2)AC/(3)AC(4)/9.1SourceReceptor12334I/OcablesI/Ocables9.19(1)3PCBI/OEMC5(1)(2)(3)(4)(5)PCBEMCPCBPCBPCBEMC/EMI123PCBPCBPCBICEMCPCB9.19.1.1SignalIntegritySI9(1)4PCB(1)(2)(3)(4)(5)(6)PCBPCBPCB[3]reflection(overshoot)(undershoot)ringingroundinggroundbounce0V2.5V3.3V5VPCBPCBPCBPCB(PCB)PCBEMCEMI(EMl)PCB10cmEMII/OEMI9(1)522ssZV1sVs1Z1LZ2LZG(0V)SVM1SZsV2SZVVSRSLsgCvgCsvCvRvLgZ1LZ2LZSVM1SZsV2SZsgCvgCsvCgZ1LZ2LZG(0V)tt9.2PCBdB90dB()20logvictimtalkdBsourceVXV=EMCEMIPCB9(1)610PCB130022100023300210002PCBPCBPCBPCBPCBPCBPCBPCBQuanticGREENFIELF2TMEESOFuWaveSPICEPCB()PCBPCBPCBPCB9.2EMC9.2.1EMCPCBPCB1EMIEMIEMI9(1)7I/Otmaxttyp2ns0.5ns1.5ns5MHz74F041ns100MHz74AL044nsPCBEMC2//0V01tdVICdt=3--1plhtphlt9.3plhtphlt9.39(1)82--TTLCMOS-9.4-3--9.2.2PCB9.1PCBfZfZfZ9(1)9fZfZPCB1PCBPCBPCBPCB2LZRjXRjfLπ=+=+100KHzEMC1/202EMI3PCB45I/O0.6pf2~6pf520nH244~18nH9(1)10PCB9.39.3.19.5()Q3Q4Q3Q49.5Q3Q430~100mA()9(1)119.6ICCVCCICCLLdi/dtIgVgIgLLdi/dt9.79.710.5mm12mΩ15nH160MHz9.24Ω9(1)12]5.0)]/(2lg[3.2[002.0++=tWSSLµHS(cm)W(cm)t(cm)tW]5.0)/2lg(3.2[002.0+=WSSLµH)2/()(21221MLLMLLL−+−=L1=L22/)(1MLL+=M1/29.3.21~1.5cm9.8(mV)9.29.2(mV)9(1)139.3.3()()9.91010~15ICdVdtdIC/⋅=dVdtdI2ns50mA0.1V.0.0011416470~1000pF9(1)14500mV256kRAM0.1µF(dI/dt)9.10()1239.4PCBPCBPCBPCBPCB9(1)15PCBPCBPCBPCBPCBEMITFMPESTPCB()PCBPCBPCBPCBPCBPCBPCBPCBPCBPCBPCBPCBTEMPESTPCBPCBPCBCISPRCENELECFCCVDE30MHz-1GHz5~40GHz9.4.1()()9.111/πd1πtr1/πd1/πd1/πtr20dB/dec1/πtr40dB/dec1/πtrdBV/MHzdBA/MHz9(1)16f1/πdATVlg206+=(dBV/MHz)1/πdf1πtrfAVlg204lg20−−=(dBV/MHz)f1/πtrftAVrlg40lg20lg2014−−+−=(dBV/MHz)dTtrµsfMHz1MHzB201gBBMHz9.119.4.2PCBI/O1()H=IA/(4πD3)A/mE=Z0IA/(2λD2)V/mZW=Z02πD/λΩ9(1)17H=πIA/(λ2D)A/mE=Z0πIA/(λ2D)V/mZW=Z0=377ΩIAAm2DmZ0Ωλm1)2)3)4)5)()377Ω6)2)(220DIAZEλπ=V/m2:H=Il/(4πD2)A/mE=Z0ILλ/(8π2D3)V/mZW=Z0λ/2πDΩ:H=IL/(2λD)A/mE=Z0IL/(2λD)V/mIAlmDmZ0Ωλm1)2)3)4)5)()377Ω6))2(20DIlZEλ=V/m39(1)1860dBLgCZZZ+=ZC7.9Df3/96.7DVAE=µV/mZC7.9Df2/63DIAfE=µV/m3/96.7DIAH=µA/m()DAfE/31.12=µV/m2)120/(πEH=µA/mVVAcm2f,MHzDm9.123m31)2)D48/ffMHz9(1)193)()4)()(Z7.9fD)(Z7.9fD)5)L(cm)λ/4(7)λ/46)()S(5)7)A(cm2)=lS(5)(6)8)E(dBµV/m)E0()+201gA+201gV(IgIIgV)9)9.131mGJB1511m100MHz10Vrmsl=6cmS=2.5cm75Ω1GJBl51RE021)=20dBV26dBV()2)D=1m48/100=0.483)6cm100MHzλ/4201g(6x2.5)=24dB4)75Ω30Ω100ΩZ300Ω5)Eo(100MHz75Ω)44dBµV/mEo(100MHz)30dBµV/m6)Eo(100MHz75Ω)44dBµV/m+20+24=88dBµV/mEo(100MHz)30dBµV/m+26+24=80dBuVm7)GJBl51RE0229dBµV/m(GJBl51AREl0224dBµV/m)60dB1/40(9(1)200.6cm)34dB30dB9.149.14lA1cm2201g(IA)IAAcm25V/20A50kHz()60A100kHz3×10cm2100kHz0.2Ω1m100kHz1)60A36dBA,2)100kHzD=148/0.1=480m3)Zc=0.2ΩZc7.9Df9.104)201g30=30dB5)Ho(100kHz)=17dBµA/mEo(100k)=30dBµV/m6)H(100kHz)=17dBµV/m+36+30=83dBµV/mE(100kH)=15dBµV/m+36+30=81dBµV/m9.4.320dB/dec40dB/dec40dB/dec40dB/dec20dB/dec-9(1)211)II1=0.64I2)I13)()1/πd1/πd40dB/dec1/πd1/πtr20dB/dec1/πtr1/πd1/πtr20dB/dec1/πtr9.3NN10m30-230MHz30dBµV/m230-1000MHz37dBµV/m9.3EMIcm24MHz10301004000B406100040074HC620504518674LS65020187.22.474AC3.5805.52.20.750.2574F3805.52.20.750.2574AS1.412020.830.15NN()PCBEMIPCB(1)I(2)f1)2)1/tr1/tr1/tr1/tr(3)9(1)229.4.4(CRT)L=I/φφI9.11()1kHz10kHz1kHz10kHz9.119(1)239.4.59.12()9.13(a)9.13(b)68HCll74HC0074HC0068HCll52MHzPCBAB2MHz1520dB9(1)24(a)(b)9.139.149.14?12.4.69(1)2530MHz1231234()(1)20H20HH(2)()9(1)2612.4.712.15L3mm1m12(i3)i2i3()9.151/1037)1039.0/()11.0(/3=×××××=−LILIDMCD31dB()()=×λ/2()λ/4()ZCMdLHZ/120=d()H/d190~550ΩGJBl515MHz5V1.2m0.3m9(45MHz)0.3V1.2µH/m120Ω45MHz3mGB9254B1)D=3m48/45Lλ/22)120×30cm2=72dBcm20.3V=-10dBV3)ZCM=120Ω+j(2π×1.2×45×1.2)=435Ω4)Eo(45MHz)=10dBµV/m5)E=10+72-10=72dBµV/m6)GJ9254B40dBµV/m32dB9(1)27()E=1430IL/(fD3)µV/mE=0.63ILf/DµV/mE=1.26ILf/DµV/mLλ/2λ/4E=120I/DµV/mI(µA)L(m)D(m)f(MHz)L2Lλ/2(λ/4)λ/2L())1)2)/dBµV3)()4)(3)(3)5)(TransferImpedance)ZTdBΩ()6)ICM(dBµA)=V(dBµV)-ZT(dBΩ)7)ICM(dBµA)µA8)1)()2)I/OI/OIO3)9(1)284)9.5I/OI/O()I/OI/OI/OI/OI/OI/OI/OI/O20H9.16PCB9(1)299.6EMC9.6.1PCBEMIVLSIPCBIC9.17TTLDIP9.18PCB9(1)30162126310()()sEfAIr−=×××v/m71410()()sEIflrπ−=×××v/mEv/mAcm2fMHzIsmAlmrmPCBEMCSMT9.19689.5.2EMI0VVinVoutVccVgnd9(1)319.202CC0VIdischargeLgndVbgdtdILVedischgndgbarg=PCB1234PCB12PCB/39(1)329.49.5.39.5.4PCB75MHzVLSI9.219(1)339.2275MHz/PCB0v0vPCBFaradayVLSIPCB9.5.5PCBPCB9(1)349.23PCB/9.5.6EMCEMI12I/O39.59.59(1)35//I/O[1]MarkI.Montrose.EMCandtheprintedcircuitboard.NewYork:IEEEPress,1999[2]ClaytonR.Paul.Introductiontoelectromagneticcompatibility.NewYork;JohnWileyandSons,1992.[3]DavidA.Weston.Electromagneticcompatibility:principlesandapplications(2nded.).NewYork:MarcelDekker,Inc.,2000[4]..1993.10[5].?