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Dc-gain enhanced folded cascode Op-amp using a new positive feedback method

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Abstract

In this paper, a novel operational amplifier is demonstrated which is established on the folded cascode Op-amp structure. A new technique of positive feedback is proposed to increase the open loop gain of Op-amp while not limiting its linearity. The proposed structure is simulated by HSPICE software using level 49 parameters (BSIM3V3) in a typical 0.18 µm CMOS technology. HSPICE simulation verifies the theoretical estimated improvements.

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Authors and Affiliations

  1. Faculty of Engineering, Shahrekord University, Shahrekord, Iran

    Majid Eslami Farsani & Noushin Ghaderi

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  1. Majid Eslami Farsani
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  2. Noushin Ghaderi
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Correspondence to Noushin Ghaderi.

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Farsani, M.E., Ghaderi, N. Dc-gain enhanced folded cascode Op-amp using a new positive feedback method. Analog Integr Circ Sig Process 89, 771–779 (2016). https://doi.org/10.1007/s10470-016-0780-7

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  • DOI: https://doi.org/10.1007/s10470-016-0780-7

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