A design philosophy for microelectronic active-RC filters

A design philosophy for microelectronically realizable active-RC filters is presented and illustrated by means of microelectronic filter examples in the frequency range from approximately 75 Hz to about 110 kHz. The design is by simulation of low-sensitivity resistively terminated inductor-capacitor filters (LCR filters). Based on an analysis of the effect of nonideal components in the active-RC filters, functional adjustment methods are developed which lead in practice to near-ideal nominal response characteristics, in many cases better than those of practical LCR filters. By matching the design process to a carefully chosen well-established manufacturing technology, the cost of the microelectronic active-RC filters is attractively low. Many of these filters in microelectronic form are in production in the U.K.