可控滤波器设计和实现

本文主要叙述用开关电容滤波器MAX262构成低通、高通、带通、陷波和全通滤波器的设计。利用DDS芯片AD9851为MAX262提供不同频率的时钟信号,通过单片机对max262内部寄存器的写操作,改变滤波器的中心频率,克服了传统滤波器中心频率不易改变的缺点。实验结果表明,该滤波器较好的滤波功能,能广泛应用于各类通信系统。

This paper introduces a switched capacitor filter, which can realize low - pass, high - pass, band - pass, all - pass and notch wave filtering function. By means of time signal with different frequency, which is produced for MAX262 by AD9851 in DDS, single chip machine＇ s writing operation for max262 internal register , this design has changed the center frequency of the filter. It overcomes shortcoming in traditional one, in which center frequency can not be changed easily. The experiment shows the filter can be applied to various communication system.