信息技术处理员知识点1

Note:enterdatainyellowcelliW3627WorkSheetminimumLinevoltageVin_min90VrmsmaximumlinevoltageVin_max264Vrsmminimumlinefrequencyfac_min50HzOutputvoltageVout38VOutputCurrentIout0.4AConverterEfficiencyEff89%OutputvoltagerippleVripple15%Noninaloperationfrequencyfres120kHzPFMIsenseclamppingvoltageVisense_pfm0.16VTransformerprimarytosecondaryturnsratioNps2.105ontimeatpeakoflineofVin_minTon3.07usIsenseclampatPWMmodeVipk0.9VTransformermagnitizinginductanceLm268uHCurrentsensingresistorRcs0.617ohmminimumtonatPFMmodeatVin_maxton_pfm_min0.186usminimumresettimeatPFMmodetrst_pfm_min0.87usMinimumoutputcapacitorCout_min112uFMaximumpreloadresistorRpre_max29kohmCoreareaAe40mm2PriminaryturnsminimumNpri31.0TurnsSecondaryturnsNsec15TurnsBiasturnsNbias4TurnsFlybackCircuitParametersSystemInputTransformerTurns10%belownorminalvalue10%abovenorminalvalue50Hzor60HzVoutpeaktoaveragevaluedevidedbyVoutaverage90kHzor120kHz0.16Vor0.2VAdjustNpssoNps*Voisaround80Vforflybackifton_pfm_min0.18us,increaseNpsand/orchosefres=90kHzand/orchoseVisense_pfm=0.2Viftrst_pfm_min1.1us,decreaseNpsand/orchooseVisense_pfm=0.2VThisisaroughestimation,needtoadjustbyrippleresult564231GNDCS/CFG1MultiVccLN+_iW3627FB/CFG2Output564231GNDCS/CFG1MultiVccLN+_iW3627FB/CFG2OutputfrequencyVisense_pfm900.161200.2ton_maxTpTd-12Vin_minNVo+3.647106-=:=Lm12Vin_minton_max()2fsηVo_cvImax1.585104-=:=RsLmVipk2Vin_minton_max0.256=:=trst_rsshortLmVipk_pfmRs1NVo1.238106-1.547106-=:=ton_rsshortVipk_pfmRsLm2Vin_max:=ton_rsshortVipk_pfmRsLm2Vin_max:=ReferencedesignlistforICevaluation90k120kflyback48V1A,NVO=80,Visense_pfm=0.16V36V0.3A,NVO=80,Visense_pfm=0.2Vbuckboost36V1A,Visense_pfm=0.20Vbuck36V1A,Visense_pfm=0.20Vtwooutput36V0.3A,7V50mA