LM137000 and OPA860/861 Operational Transconductance Amplifiers (OTAs) from Texas Instruments. Operational Transconductance Amplifiers produce an output current proportional to a differential input. The transconductance, or gain, of the OTA can be controlled via a current which makes the devices suitable for a wide range of voltage or current controlled applications such as filters, oscillators, multipliers and variable gain cells.
