简介:InviewofthelimitationsofaRn-GnmodelinthelowfrequencyrangeandthedefectsofanEn-Inmodelincommonusenow,thispaperbuildsacompleteEn-Inmodelaccordingtothetheoryofrandomharmonic.Theparametersforthelow-noisedesignsuchastheequivalentinputnoisyvoltageEns,theoptimumsourceimpedanceZsoptandtheminimumnoisefigureFmincanbecalculatedaccuratelybyusingthisEn-Inmodelbecauseitconsidersthecoherencebetweenthenoisesourcesfully.Moreover,thispaperpointsoutthatitwillcausethemaximum30%miscalculationwhenneglectingtheeffectsofthecorrelationcoefficient7.Usingtheseries-seriescircuitsasanexample,thispaperdiscussesthemethodsfortheEn-InnoiseanalysisofelectroniccircuitspreliminarilyanddemonstratesitscorrectnessthroughthecomparisonbetweenthesimulatedandmeasuredresultsoftheminimumnoisefigureFminofasinglecurrentseriesnegativefeedbackcircuit.
简介::Twonovelpoly[(3-alkyhhiophene-2,5-diyl)-(benzylidenequinomethane-2,5-diyl)s]derivatives,poly[(3-butylthiophene-2,5-diyl)-(p-N,N-dimethylamino)benzylidenequinomethane-2,5-diyl)](PBTDMABQ)andpoly[-(3-octylthiophene2,5-diyl)-(p-N,N-dimethylamino)benzylidenequinomethane-2,5-diyl)](POTDMABQ),weresynthesized.Thebandgapsofthetwopolymersarecalculatedas1.75eVforPBTDMABQand1.69eVforPOTDMABQ,respectively.Thehomogenousfilmsofthetwopolymerswerepreparedandtheirthird-ordernonlinearopticalpropertieswerestudiedbythebackwarddegeneratefour-wavemixingat532nm.Byusingtherelativemeasurementtechnique,thethird-ordernonlinearopticalsusceptibilitiesofPBTDMABQandPOTDMABQarecalculatedas5.62×10^-9and1.22×10^-8ESU,respectively.Itisfoundthatsubstitutedalkygroupshavestrongeffectsonthebandgapandnonlinearopticalpropertiesofthetwopolymers.Therelativelybigthird-ordernonlinearopticalsusceptibilitiesandsmallbandgapofPOTDMABQresultedmainlyfromthelongeralkylwithstrongelectron-donatingabilitycanenhancethedelocationdegreeofconjugatedπelectronics.
简介:<正>英飞凌科技股份公司推出全新的650VCoolMOSTMC6/E6高性能功率MOSFET系列。该产品系列将现代超级结(SJ)器件的优势(如低导通电阻和低容性开关损耗)与轻松控制的开关行为及体二极管高牢固性融合在一起。基于同样的技术平台,C6器件针对易用性进行了优化,而E6器件则旨在提供最高效MOSFET系列。该产品系列将现代超级结(SJ)器件的优势(如低导通电阻和低容性开关损耗)与轻松控制的开关行为及体二极管高牢固性融合在一起。基于同样的技术平台,C6器件针对易用性进行了优化,而E6器件则旨在提供最高效率。CoolMOSTMC6/E6是来自英飞凌的第六代市场领先的高压超级结功率MOSFET。全新的650VCoolMOSTMC6/E6器件具备快速、可控的开关性能,适用于效率和功率密度是关键要求的应用。650VCoolMOSTMC6/E6器件易于应用,是各种高能效开关产品的理想之选,例如笔记本电脑适配器、太阳能逆变器和其他需要额外击穿电压裕量的开关电源(SMPS)产品。相对于CoolMOSTMC3650V系列,全新650VCoolMOSTMC6/E6器件输出电容(Eoss)的储电量降幅高达20%,而C6/E6器件经过改进的体二极管具备更高的硬换相耐受性,并可使反向恢复电荷降低约25%。得益于调谐栅极电阻的平衡设计,C6/E6器件的开关行为能够避免过高的电压和电流变化率。邹勉摘编