Fully-Differential Universal Frequency Filter with Dual-Parameter Control of the Pole Frequency and Quality Factor

The paper presents a proposal of modified 2
^nd
-order fully-differential universal frequency filter. Both the pole frequency and quality factor (controlled without disturbing each other) of the filter can be controlled by two independent parameters (i.e. dual-parameter control) in order to increase the range of their control. It is the main improvement in comparison to recent state-of-the-art. The function of the proposed filter has been verified by PSpice simulations and also by experimental measurements.