New Very Low Frequency Oscillator Using only a Single CFOA

D. K. Srivastava¹, V. K. Singh^1, and R. Senani²

¹Electronics Engineering Department, Institute of Engineering and Technology, Lucknow, 226021 India

²Division of Electronics and Communication Engineering, NetajiSubhas Institute of Technology, Sector 3, Dwarka, New Delhi, 110078, India

Cite this paper

D. K. Srivastava, V. K. Singh and R. Senani. New Very Low Frequency Oscillator Using only a Single CFOA. American Journal of Electrical and Electronic Engineering. 2015; 3(1):1-3. doi: 10.12691/AJEEE-3-1-1

Abstract

Some time back, Elwakil presented a systematic method of realizing Very Low frequency (VLF) oscillators using current feedback operational amplifiers (CFOA) and demonstrated that the classical Wienbridge oscillator, employing the concept of composite resistor (containing two positive and one negative resistance) can be tailored to generate VLF oscillations. The circuit proposed by Elwakil, however, required two CFOAs along with six resistors and two capacitors. The object of this paper is to report a new VLF oscillator circuit which, in contrast to Elwakil’s circuit, requires onlya single CFOA. The workability of the new circuit has been demonstrated by experimental results using commercially available AD844type CFOAs.

Keywords

Oscillators, Current-feedback-operational amplifiers, current-mode circuits, single element controlled oscillators, very low-frequency oscillators

Copyright

This work is licensed under a Creative Commons Attribution 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/

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