用第三代电流传送器设计n阶有源滤波器

摘要

提出了一种基于第三代电流传送器(CCIII)的电流模式n阶通用滤波器的设计方法，导出了设计公式，利用该方法可生成n阶高通、低通、带通滤波器，所产生的n阶滤波电路由n个CCIII+、2 n个无源元件构成。以二阶滤波器为例分析了高通、低通、带通滤波电路，结果显示各滤波电路的无源灵敏度和有源灵敏度都很低，以极点角频率106 rad/s为例，用PSPICE软件对电路进行了仿真。结果表明，高通滤波器的截止频率为790 kHz，低通滤波器的截止频率为149 kHz，带通滤波器的中心频率为139 kHz。数据表明该设计方法可行。%A design method for current-mode wth-order universal filter based on CCIII was presented, the design formula derivation was performed. The wth-order high-pass, low-pass and band-pass filters were obtained by the design method. The circuits consisted of n CCIII+ and 2 n passive components were analyzed, the passive and active sensitivities of the two-order high-pass, low-pass and band-pass filter circuits are both low. For example, when pole angular frequency was 106rad/s, the circuit was simulated with PSPICE. Results show that high-pass filter cut-off frequency is 790 kHz, low-pass filter cut-off frequency is 149 kHz and band-pass filter center frequency is 139 kHz. Data show that the design theory is correct and the design method is feasible.