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An enhanced folded cascode Op-Amp using positive feedback and bulk amplification in 0.35 μm CMOS process

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Abstract

In this paper a new operational amplifier is presented which is based on the conventional folded cascode Op-Amp structure. A new method of positive feedback is used to increase dc-gain. This method does not limit the range of the output voltage swing. True performance of the Op-Amp in higher output voltage swings is another advantage of the proposed Op-Amp in comparison with the conventional structures. Bulk amplification and positive feedback are used to improve the Op-Amp specifications. Proposed structure has been simulated by HSPICE software using level 49 parameters (BSIM3v3) in a typical 0.35 μm CMOS technology. The HSPICE simulation confirms the theoretical estimated improvements.

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Acknowledgment

The authors are grateful to reviewers for their valuable comments.

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Authors and Affiliations

  1. Department of Electrical Engineering, Microelectronic Research Laboratory, Urmia University, Urmia, Iran

    Ali Dadashi, Shamin Sadrafshari, Khayrollah Hadidi & Abdollah Khoei

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  1. Ali Dadashi
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  2. Shamin Sadrafshari
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  3. Khayrollah Hadidi
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  4. Abdollah Khoei
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Correspondence to Ali Dadashi.

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Dadashi, A., Sadrafshari, S., Hadidi, K. et al. An enhanced folded cascode Op-Amp using positive feedback and bulk amplification in 0.35 μm CMOS process. Analog Integr Circ Sig Process 67, 213–222 (2011). https://doi.org/10.1007/s10470-010-9561-x

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  • DOI: https://doi.org/10.1007/s10470-010-9561-x

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