Table of Contents
ISRN Electronics
Volume 2013 (2013), Article ID 987867, 6 pages
Research Article

New Voltage Mode Universal Filters Using Only Two CDBAs

1Department of Electronics and Communication Engineering, Echelon Institute of Technology, Kabulpur, Jasana-Manjawali Road, Faridabad, Haryana 121101, India
2Department of Electronics and Communication Engineering, Faculty of Engineering and Technology, HRCT Group of Institutions, 7th Km Stone, Meerut Road, Morta, Ghaziabad 201001, India
3Division of Electronics and Communication Engineering, Netaji Subhas Institute of Technology, Sector-3, Dwarka, New Delhi, Delhi 110078, India

Received 13 November 2012; Accepted 13 December 2012

Academic Editors: E. I. El-Masry, R. Luzzi, L.-F. Mao, and Y. Takahashi

Copyright © 2013 J. K. Pathak et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Two new configurations for voltage mode universal filters (VMUFs) using only two current differencing buffered amplifiers (CDBAs) are proposed. Both of the new configurations can realize all the five standard types of the filters, namely, low pass (LP), high pass (HP), band pass (BP), band stop (BS), and all pass (AP), from the same topology. In contrast to previously known CDBA-based VMUFs, the new configurations do not need an additional active device for voltage inversion to realize all pass functions. The proposed configurations offer the tunability of the natural angular frequency , quality factor , or the bandwidth (BW) through separate virtually grounded resistors. Moreover, both circuits have resistive input impedance (which can be made high) and a low output impedance to facilitate easy cascading without additional buffers. PSPICE simulation results, based upon commercially available AD844 ICs to implement the CDBA, are included which confirm the practical workability of the new VMUF configurations.