A new universal biquad filter using differential difference amplifiers and its practical realization
The differential difference amplifier (DDA) was introduced more than two decades back and its several applications as well as bipolar/CMOS implementations have been reported so far. This paper presents a new second order multiple-input-single-output type universal filter configuration using only two DDAs along with only five passive components which can realize all the five generic filter functions from the same configuration under various conditions in terms of the four input signals. Furthermore, it is demonstrated that DDA-based circuits can be practically implemented using commercially available video differencing amplifier IC AD830.
universal biquads differential difference amplifier analog circuits active filters