论文部分内容阅读
R有源滤波器的工作频率可以比RC有源滤波器高1～2个数量级。这样,为有源滤波器的工作频率扩展到视频范围创造了条件。但是,R有源滤波器的二阶节电路需要两只高增益宽频带运放进行组合。这样,不仅对集成高阶R有源滤波器带来困难;而且两只高增益宽频带运放闭环应用后,将带来难以消除的自激振荡。本文首先介绍了常规六阶R有源滤波器的设计和存在问题;然后提出了采用一只运放构成二阶节电路的设想。
R active filter operating frequency can be higher than the RC active filter 1 to 2 orders of magnitude. In this way, the working frequency of the active filter is extended to the video range. However, the second-order section of the R active filter requires two high-gain wideband op-amps to be combined. In this way, not only is it difficult to integrate a high-order R active filter, but also the closed-loop application of two high-gain broadband operational amplifiers will bring about self-oscillation which is hard to eliminate. This paper first introduces the design and existing problems of the conventional sixth-order R-active filter. Then, the idea of using a single op-amp to form a second-order section circuit is proposed.