Transforming OTA-C filters from voltage- to current-mode

A suitable method for transforming OTA-C filter circuits working in voltage-mode to current-mode is presented. First, the ideal behavior of the OTA is modeled using the nullor concept. Second, the transformation process is conducted by applying a set of four basic rules related to the interconnection pattern of the nullors. Third, the nullors of the transformed circuit are synthesized by OTAs. Finally, the computation of the transfer function of the given and the transformed circuit demonstrates the appropriateness of this method to be used as an analytical tool.