The week's pick
Reseach Article
A Novel High Input Impedance AC-Coupled Buffer
| Communications on Applied Electronics |
| Foundation of Computer Science (FCS), NY, USA |
| Volume 5 - Number 4 |
| Year of Publication: 2016 |
| Authors: Emad Alnasser |
10.5120/cae2016652278
|
Emad Alnasser . A Novel High Input Impedance AC-Coupled Buffer. Communications on Applied Electronics. 5, 4 ( Jun 2016), 17-22. DOI=10.5120/cae2016652278
Abstract
Designing an AC-coupled buffer that works in the extremely low frequency range, a few Hertz, when the coupling capacitor is very small, a few pico-farads, forms a complex designing problem. In this article, a novel and simple scheme is proposed to realize such an AC-coupled buffer. The proposed buffer shows extremely high input impedance at the low frequencies. This feature enables the proposed buffer to capture extremely low frequency signals which is coupled to it through a very small capacitor. The main advantage of the proposed method is that, it can be implemented on a chip or by using general purpose discrete electronic components very easily. The characteristics of the proposed buffer have been obtained and measured experimentally, analytically and, by using a computer aided design software.
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