Active Filter Design Using Operational Transconductance Amplifiers: A Tutorial

Basic properties of the Operational Transconductance Amplifier (OTA) are discussed. Applications of the OTA in voltage-controlled amplifiers, filters, and impedances are presented. A versatile family of voltage-controlled filter sections suitable for systematic design requirements is described. The total number of components used in these circuits is small, and the design equations and voltage-control characteristics are attractive. Limitations as well as practical considerations of OTA based filters using commercially available bipolar OTAs are discussed. Applications of OTAs in continuous-time monolithic filters are considered