A simple predistortion technique for active filters

This article deals with the predistortion of active-
RC
filters to compensate for the accountable nonideal performance of the operational amplifiers (OA's). In particular, the predistortion attempts to compensate the effect of the finite gain-bandwidth product (GB) of the OA's. This method can be used for circuits consisting of any number of OA's. The method realizes not only the specified pole frequency
\omega_{\rho}
and pole
Q
factor
Q_{\rho}
as some other methods do, but also the exact gain requirement at a specified frequency of importance. In specific examples, it will also be shown how to choose the parameters in the network to attain minimum pole sensitivity due to the GB's of the OA's, while predistortion is achieved. This method is simple enough that the design of most second-order active-
RC
filters can be implemented in a programmable calculator.