双二阶有源R滤波器的转移函数及其实现

TRANSFER FUNCTIONS OF SECOND ORDER FILTERS WITH REALIZATIONS

本文用系统分析方法推导出了双二阶有源R网络的状态方程和转移函数,并讨论了转移函数的极点。由转移函数的表达式可知,从运放输出端只能实现低通和带通滤波器,要实现高通或带阻滤波器就必须从运放的输入端取信号。文中还举例说明了选取电压传输系数实现双二阶有源R滤波电路的方法。

In this paper, the state equation and transfer functions of second order networks are derived systematically and the poles of transfer fuctions are descussed. According to the expressions of transfer fuactions, we know that LP and BP filters can be only realized from the output terminals of oprational amplifiers and that HP and BS filters must be realized from the input terminals of oprational amplifiers. It is also illustrated to choose voltage transmission ratios for realization of second order filters