Abstract
In this paper, a low voltage and ultra low power operational transconductance amplifier (OTA) is presented. As will be shown, the transient response and open loop gain of the proposed OTA are improved using adaptive biasing and DC gain enhancement techniques. The contributions of the proposed OTA are ultra low power consumption (only 3.977 μw), low supply voltages (±0.6 V), high swing, high speed, and high gain. It can clearly be seen that for the proposed OTA, the gain of the differential half-circuit in the input stage (A d ), DC gain (A 0), gain bandwidth (GBW), and slew rate (SR) are increased, whereas the settling time (T S ) is decreased. The results of simulations done using 0.18 μm Silterra CMOS process technology and the measurement results are presented to validate and compare the advantages of this work and other related works.
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This paper is the result of a research project supported by Kharazmi University.
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H. Fathabadi is also currently a Post-Doctoral researcher at National Technical University of Athens, Greece.
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Fathabadi, H. Ultra Low Power Improved Differential Amplifier. Circuits Syst Signal Process 32, 861–875 (2013). https://doi.org/10.1007/s00034-012-9475-1
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DOI: https://doi.org/10.1007/s00034-012-9475-1