Low Power Operational Transconductance Amplifier (OTA) with Enhanced DC Gain and Slew-Rate

Abstract:

This paper presents a low-voltage differential operational transconductance amplifier (OTA) with enhanced DC gain and slew-rate. Based on the current mirror OTA topology, the optimization techniques are discussed in this work. The proposed structure achieves enhanced DC gain, unit gain frequency (UGF) and slew-rate (SR) with adding four devices. The design of the OTA is described with theory analysis. The OTA operates at the power supply of 1.8V. Simulation results for 0.18μm standard CMOS technology show that the DC gain increases from 60.6dB to 65dB, the UGF is optimized from 2.5MHz to 4.3MHz, the SR is enhanced from 0.88 V/μs to 4.8 V/μs with close power consumption dramatically.

• Periodical: Applied Mechanics and Materials (Volumes 411-414)
• Pages: 1645-1648
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.411-414.1645
• Online since: September 2013
• Authors: Xiao Zong Huang, Lun Cai Liu, Jian Gang Shi, Wen Gang Huang, Fan Liu, Jun Luo, Zhou Liang
• Keywords: Enhanced Slew-Rate, High DC Gain, Low Power, OTA

References

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