High-Gain Class-AB OTA with Low Quiescent Current

  • Jeongjin RohEmail author


High-performance operational transconductance amplifier (OTA) is designed for switched-capacitor applications. Without using a cascoded output stage, which limits the voltage swing, the output resistance is significantly increased for high DC gain by accurately controlling the output current. Also, the output stage has class-AB operation, so the overall power efficiency is improved. With significantly low quiescent current, the presented new OTA achieves higher DC gain than conventional OTAs. Theoretical analysis and HSPICE simulations prove the performance of the new OTA.

Key Words

operational transconductance amplifier OTA transconductance slew rate 


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Copyright information

© Springer Science + Business Media, Inc. 2006

Authors and Affiliations

  1. 1.Department of Electrical Engineering and Computer ScienceHanyang UniversityAnsanKorea

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