文章编号:1673-5196(2023)01-0083-04基于模拟电感的二阶状态可调滤波器设计李永安*1,2,侯婧嫱1(1.陕西国际商贸学院信息工程学院,陕西西安712046;2.咸阳师范学院物理与电子工程学院,陕西咸阳712000)摘要:基于集成运放的主极点模型,首先导出了接地电容双运放模拟电感的等效导纳表达式,它表明只有在理想运放条件下,电路才能等效为一个数值为CR2的电感.以此为依据,并以经典的无源二阶带通滤波器为拓扑,用元件替换法设计了一个二阶状态可调滤波器.该滤波器不仅可实现带通滤波,而且可以实现低通滤波功能.电路仅使用两个集成运放,而且使用两个接地电容,因此电路适宜集成.计算机仿真表明,电路的工作频率高达10MHz,Q可高达100,并正确地解释了高频情况下出现Q增强和fo减弱的原因.关键词:Q增强和fo减弱;状态可调滤波器;模拟电感;集成运放中图分类号:TN715.3文献标志码:ADesignofsecond-orderstate-tunedfilterusingsimulatedinductanceLIYong-an1,2,HOUJing-qiang1(1.SchoolofInformationandEngineering,ShaanxiInstituteofInternationalTrade&Commerce,Xi’an712046,China;2.SchoolofPhysicsandElectronicEngineering,XianyangNormalUniversity,Xianyang712000,China)Abstract:Basedonthedominant-polemodeloftheintegratedoperationalamplifier(OpAmp),thee-quivalentadmittanceexpressionofthesimulatedinductanceusinggroundedcapacitorsanddualopampsisfirstderived,whichshowsthatonlyunderidealopampconditions,thecircuitcanbeequivalenttoanin-ductorwithavalueofCR2.Basedonthatandcombinedwiththeclassicpassivesecond-orderband-passfil-tertopology,asecond-orderstate-tunedfilterisdesignedbythecomponentreplacementmethod,whichcannotonlyrealizeband-passfilteringbutalsorealizelow-passfiltering.WiththecircuitusingonlytwoOpAmpsandtwogroundedcapacitors,thecircuitissuitableforintegration.Thecomputersimulationre-sultshowsthatthecircuitcanrunupto10MHz,andQcanbeashighas100.Inaddition,thereasonforQenhancementandfoweakeningunderhigh-frequencyconditionsiscorrectlyexplained.Keywords:Qenhancementandfoweakening;state-tunedfilter;simulatedinductance;integratedopera-tionalamplifier现代集成电路越来越趋于微型化,无源电感的大尺寸和低品质因数已无法满足集成要求,因此需要研究有源电感来解决这一问题.所谓有源电感,...
