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A Novel High Input Impedance AC-Coupled Buffer

Emad Alnasser. Published in Circuits and Systems.

Communications on Applied Electronics
Year of Publication: 2016
Publisher: Foundation of Computer Science (FCS), NY, USA
Authors: Emad Alnasser

Emad Alnasser. A Novel High Input Impedance AC-Coupled Buffer. Communications on Applied Electronics 5(4):17-22, June 2016. BibTeX

	author = {Emad Alnasser},
	title = {A Novel High Input Impedance AC-Coupled Buffer},
	journal = {Communications on Applied Electronics},
	issue_date = {June 2016},
	volume = {5},
	number = {4},
	month = {Jun},
	year = {2016},
	issn = {2394-4714},
	pages = {17-22},
	numpages = {6},
	url = {},
	doi = {10.5120/cae2016652278},
	publisher = {Foundation of Computer Science (FCS), NY, USA},
	address = {New York, USA}


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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AC-coupled buffer, impedance, frequency response, noise, generalized impedance converter