采用MO-CFTA和MO-CCCCTA的电流模式KHN滤波器

Current-mode KHN filter based on MO-CFTA and MO-CCCCTA

针对现有电流模式Kerwin-Huelsman-Newcomb(KHN)滤波器的不足,借助KHN电路对应的信号流图,设计了一种由一个多输出电流跟随跨导放大器(MO-CFTA)和一个多输出电流控制电流传输跨导放大器(MO-CCCCTA)及2个接地电容构成的电流模式KHN滤波器。它能同时实现低通(LP)、高通(HP)、带通(BP)、带阻(BR)和全通(AP)5种滤波功能,其极点频率与品质因数能由偏置电流独立调整,并具有无源与有源灵敏度低、使用元件少、输入阻抗低和输出阻抗高、适于集成等优点。采用PSPICE对电路进行了仿真,所得结果验证了理论分析的正确性。

Aiming at the deficiency of the existing Kerwin-Huelsman-Newcomb(KHN)filter,a current mode KHN filter by consisting of a Multiple-Output Current Follow Transconductance Amplifier(MO-CFTA),a Multiple-Output Current Controlled Current Conveyor Transconductance Amplifier(MOCCCCTA)and two grounded capacitors are designed by using the signal flow diagram corresponding to the KHN circuit.The circuit can realize five kinds of filter function simultaneously including Low Pass(LP),High Pass(HP),Band Pass(BP),Band Reject(BR)and All Pass(AP).Its pole frequency and the quality factor can be independently adjusted by bias current.The circuit has many advantages,such as lower passive and active sensitivity,fewer components,low input impedance and high output impedance,suitable for integration.The performances of the proposed circuit are illustrated by PSPICE simulation,and the simulation results verify the correctness of the theoretical analysis.