在各种测量系统中经常要用到模拟滤波器,而普通的RC滤波器是很难达到理想的滤波效果的,因为RC滤波器的截止频率是非线性调节的,即使采用多个电阻或电容组成可控网络,其截止频率也是离散的。 本文介绍的由AT89C51单片机和MAX292构成的截止频率可任意设置的有源模拟滤波模块,其最大优点在于截止频率可由单片机编程控制,设置简单,滤波效果好, Analog filters are often used in a variety of measurement systems, and ordinary RC filters are difficult to achieve the desired filtering effect, because the cut-off frequency of the RC filter is non-linear adjustment, even with multiple resistors or capacitors Controllable network, the cut-off frequency is also discrete. This article describes the AT89C51 microcontroller and the MAX292 cut-off frequency can be set to any active analog filter module, the biggest advantage is that the cut-off frequency can be programmed by the microcontroller, set up a simple, good filtering,