摘要
介绍了一种新型的跟踪低通滤波器的原理及实现方法.该跟踪低通滤波器用八阶椭圆型开关电容滤波器MAX293构成低通滤波电路,输入信号的频率通过单片机的测量、修正、倍频处理后输出作为MAX293的时钟控制频率,用以控制MAX293的截止频率从而实现跟踪滤波.实验证明,对于0.1 Hz^25 kHz的信号,跟踪低通滤波器的截止频率相对误差小于1%.
The principle and method of the tracking low-pass filter were discussed. The MAX293, a special chip for filtering purpose, formed the nucleus of the low-pass filtering circuit. A single chip microcomputer was used to measure and multiplicate the frequency of tracked signal. By using the frequency-multiplicated signal to control the clock of MAX293, the tracking filtering was implemented. Experiment result shows that the effect of the filtering is very good at the range of frequency bettween 0. 1 Hz and 25 KHz.
出处
《电子器件》
CAS
2007年第4期1239-1241,1245,共4页
Chinese Journal of Electron Devices
基金
重庆市自然科学基金资助(8597)
