蓄电池内阻测试仪前置可选频带通滤波器设计

Design of optional frequency band pass prefilter for battery internal resistance tester

针对多频点蓄电池内阻测试法双低频测试信号滤波问题,设计基于MAX267有源带通滤波器芯片的可选频4阶切比雪夫带通滤波器。通过改变基准输入时钟频率信号,实现带通滤波器通带中心频率的切换。详细介绍了这种前置变频带通滤波器级联方式、切比雪夫滤波器选型配置、可编程引脚F_n、Q_n的配置方法、外围级联电路计算以及可变基准时钟信号的产生方法。外围电路十分精简,各中心频率通带幅频性能良好,满足工程需求。

Aiming at the filtering problem of low double-frequency test signal in battery internal resistance test,this paper puts forward a design based on MAX267 active band-pass filter chip optional frequency 4 order Chebyshev band pass filter. By changing the reference input clock fre- quency signal,it realizes the band-pass filter center frequency switching. It gives cascade way of the variable frequency band pass prefiher,con- figuration of chebyshev filter,configuration method of programmable pins of Fn and Qn ,calculati^n of peripheral cascade circuit and generation method of variable reference clock signal in detail. The peripheral circuit is very simple. The center frequency pass band performance is good for the＇ engineering requirements.