A CMOS multi-gain transconductance amplifier and its applications

  • Hussain Alzaher
Mixed Signal Letter


Transconductance amplifier (gm) based circuits are attractive due to their inherent programmability features. Single output gm’s are often replaced by multi-output gm’s to reduce the number of active devices for a given application. However, this usually results in losing the circuit programmability features. This work shows that this problem can be circumvented through adopting a new programmable multi-gain gm. The advantages of the proposed multi-gain gm are demonstrated using two filter design examples. They show that the proposed multi-gain gm reduces the number of active devices by two-third compared with their single output gm based counterparts while maintaining their versatile programmability characteristics. Experimental results obtained from a 0.18 μm CMOS process for one of the applications are provided.


Transconductance amplifier Programmable devices CMOS analog filter design 



The author would like to thank King Abdulaziz City for Science and Technology (KACST) for the financial support (Project No. AT-32-94).


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© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Electrical Engineering DepartmentKing Fahd University of Petroleum and MineralsDhahranSaudi Arabia

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