具有反馈偏置的折叠共源共栅运算放大器

Folded cascode operational amplifier with feedback bias

文章分析了基于传统偏置的折叠共源共栅运算放大器,提出了一种具有反馈偏置的折叠共源共栅运算放大器;在不降低运放其他性能指标的前提下,抑制了折叠共源共栅运放由于共模输入电平变化以及工艺失配而造成的尾电流源的电流变化,稳定了运放的直流工作点,提高了运放的共模抑制比。

This paper analyzes the drawback of traditional biased folded cascode operational amplifier and proposes a new biased folded cascode operational amplifier. This new circuit restrains the variety of the tail current source of the folded cascode for the variety of input common voltage and mismatch. The new circuit not only stabilizes the operational point of the amplifier and increases the CMRR,but it also reduces the other performance of the amplifier.