论文部分内容阅读
本文论述了基于共模负反馈的平衡运放的研制。研制得到的平衡运放不仅具有很好的常规特性而且还有极好的共模信号抑制能力。鉴于平衡运放在设计上的特殊性,本文详细讨论并比较了它与一般的双端输出运放的区别和优点,并提出了基于共模负反馈实现平衡运放的具体方法。电路设计采用了PSPICE辅助分析。芯片投片的测试结果表明,在一基本平衡结构单元中,当输入共模电压为2V时,输出共模电压低于50μV,完全达到设计要求。它可以被广泛用于连续时间滤波器、开关电容滤波器、A/D以及其它模拟电路领域。
This article discusses the development of balanced op amps based on common-mode negative feedback. Balanced operational amplifier developed not only has good conventional characteristics but also excellent common mode signal rejection. In view of the particularity of the balanced op amp, this paper discusses and compares the differences and advantages between the op amp and the general double-ended op amp and puts forward the specific method to balance the op amp based on the common mode negative feedback. Circuit design used PSPICE auxiliary analysis. The test results show that, in a basic balanced structure unit, when the input common-mode voltage is 2V, the output common-mode voltage is lower than 50μV, which fully meets the design requirements. It can be widely used in continuous-time filters, switched capacitor filters, A / D and other analog circuits.