Novel Universal Filter Using Only Two Current Active Elements

In the paper, the process of universal frequency filter design with single-input and multiple-output current followers is shown. The filter can operate at very high frequencies and with a very low supply voltage, without affecting the signal-to-noise ratio. The filter design starts from an autonomous circuit with general current elements referred to as DOCAs (dual output current amplifiers). The characteristic equation (CE) of this circuit is successively modified to be capable of controlling some parameters of the designed filter and setting the value of the quality factor independently. The paper also contains verification results of the universal filter characteristics based on a 3rd-order behavioral model of the UCC (Universal Current Conveyor).