Implementation of True Current Amplifiers via Commercial Integrated Circuits

The paper proposes a methodology for implementing true current amplifiers, i.e., amplifiers with low-impedance current inputs and high-impedance current outputs, from commercial integrated circuits. The possibilities of implementing a true current instrumentation amplifier are analyzed, the simplification of which results in a true current operational amplifier (TCOA) as an adjoint circuit to a known voltage operational amplifier. Basic measurements are made on the implemented TCOA specimen and its operation in a current-mode Sallen-Key filter is verified.