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

  • Ali Dadashi
  • Shamin Sadrafshari
  • Khayrollah Hadidi
  • Abdollah Khoei
Article
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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.

Keywords

Folded cascode Bulk driven Positive feedback block Linearity 
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Notes

Acknowledgment

The authors are grateful to reviewers for their valuable comments.

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Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • Ali Dadashi
    • 1
  • Shamin Sadrafshari
    • 1
  • Khayrollah Hadidi
    • 1
  • Abdollah Khoei
    • 1
  1. 1.Department of Electrical Engineering, Microelectronic Research LaboratoryUrmia UniversityUrmiaIran

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