状态变量有源RC滤波器最大动态范围的研究

高阶有源RC滤波器存在着多种实现方法，而级联实现法在工程上得到广泛应用，因为级联滤波器的设计和调整相当方便。然而，在级联滤波器中．一个更关键的指标是它的动态范围。获得好的动态范围是指两个层面的问题：(1)确保级联内部信号电平不会对各运放产生过激励；(2)确保带内信号电平不会小到被噪声淹没。为了解决上述问题，在详细讨论了包括双二次型在内的状态变量有源RC滤波器最大动态范围的实现问题的基础上给出了实用的设计公式。

Research on the maximum dynamic-range of biquad state variable active RC filters

There are several ways which can realize a high-order active RC filter. The cascade realization is widely used in industry because cascade filters are relatively straightforward to design and tune.However,in cascade filters,more crucial quota is its dynamic range. To achieve good dynamic range is of two aspects.Firstly to ensure that signal levels within the cascade would not become excessively large to overdrive every amps; Secondly to ensure that in-band signals would not become so small that they become depressed into the noise. Among the articles on active RC filters, the problem of dynamic-range is less involved. In this paper,the realization of the maximum dynamic-range of state variable active RC filters and biquad are discussed in details,and practical design formulas are also given.