In this study, a local positive feedback technique is proposed to enhance the performance of the folded cascode (FC) operational transconductance amplifier (OTA) when working in its saturation region. The enhanced FC-OTA has a higher gain bandwidth (GBW), higher DC gain and higher slew rate (SR) over its conventional counterparts and popular recycling FC-OTAs. The proposed enhanced FC-OTA is implemented by reusing the current generated by the input transistors through the proposed local positive feedback loop to provide additional transconductance and negative resistance. It is then fabricated with SMIC 180nm process. To verify the effectiveness of the proposed FC-OTA performance enhancement strategy, extensive mathematical analysis, small-/large-signal stability analysis, simulation and experimentation are thoroughly investigated in this study. Simulation and experimental results agree well with the theoretical analysis and the expected performances, which corroborates the control design.

中文翻译：

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基于鲁棒局部正反馈的非循环折叠级联 OTA 性能增强策略

在这项研究中，提出了一种局部正反馈技术，以提高折叠共源共栅 (FC) 运算跨导放大器 (OTA) 在饱和区工作时的性能。增强型 FC-OTA 比传统同类产品和流行的回收 FC-OTA 具有更高的增益带宽 (GBW)、更高的直流增益和更高的压摆率 (SR)。建议的增强型 FC-OTA 是通过重新使用输入晶体管产生的电流通过建议的本地正反馈回路来实现的，以提供额外的跨导和负电阻。然后采用中芯国际 180nm 工艺制造。为了验证所提出的 FC-OTA 性能增强策略的有效性，本研究对广泛的数学分析、小/大信号稳定性分析、仿真和实验进行了深入研究。