采样率可编程的数据采集器设计∗

摘要

For the problem of poor universality which caused by the fixed data sampling rate,a design method of data acquisition rate of alternative sampling has been put forward by programming. Application of switched-capacitor filter achieves an anti-aliasing filter that the cut-off frequency can be changed. Use the VHDL program to control the sam-pling and coding mode,the acquisition design with optional sampling rate can be achieved. The experimental results show that this design can choose five sampling rate of 1 ksample/s, 5 ksample/s, 10 ksample/s, 25 ksample/s, 50 ksample/s to sample signals of the frequencies less than 10 kHz,and it’s also practical and versatile.%针对数据采集设备采样率固定，通用性差的问题，提出了一种通过编程实现采样率可选择的数据采集器的设计方法。设计中应用开关电容滤波器，实现了截止频率可以改变的抗混叠滤波器设计。通过VHDL程序对采样、编帧方式的控制，实现了采样率可选的采集器设计。实验表明，采集器可选择1 ksample/s、5 ksample/s、10 ksample/s、25 ksample/s、50 ksample/s这5种采样率采集10 kHz以下的信号，具有实用价值和通用性。