一种亚阈值有源共源共栅补偿运算放大器  

A subthreshold active cascade compensation operational amplifier

作　　者：张春茗 王梦海 严展科 ZHANG Chunming;WANG Menghai;YAN Zhanke(College of Electronic Engineering,Xi’an University of Post and Telecommunications,Xi’an 710121,China)

机构地区：[1]西安邮电大学电子工程学院,陕西西安710121

出　　处：《现代电子技术》2020年第6期13-17,共5页Modern Electronics Technique

基　　金：国家科技重大专项课题资助项目(2016ZX03001003 006)。

摘　　要：针对低压低功耗高增益高带宽应用背景的运算放大器,提出一种新型亚阈值有源共源共栅补偿(SACC)运算放大器。通过使用亚阈值跨导提升辅助放大器,以非常低的功耗成本改善整体电路的带宽,同时有效地减小补偿电容的数值,且输出级采用动态前馈结构,显著提升电路摆率。当驱动10 pF容性负载时,放大器的补偿电容仅需60 fF即可实现稳定,从而大大减小了放大器的版图面积。提出的放大器在28 nm CMOS工艺下设计并验证,并且当驱动10 pF的容性负载时,仿真结果表明,在0.9 V电源电压下,可实现69.5 dB的直流增益和13.3 MHz的增益带宽积,且功耗仅为4.5μW。此外,提出的放大器与现有的方案相比较具有更好的品质因数(FOM)。A novel subthreshold active cascade compensation(SACC)technique is proposed for the application background of low voltage,low power consumption,high gain and high bandwidth.The booster amplifier is promoted by means of the subthreshold transconductance to improve the bandwidth of the whole circuit at very low cost of power consumption,and effectively reduce the value of the compensation capacitor.The slew rate of the circuit is improved significantly with the dynamic feed-forward structure adopted in the output stage.The required compensation capacitance to stabilize the amplifier is only 60 fF when driving a 10 pF capacitive load,so that the layout area of the amplifier is greatly reduced.On the basis of the 28 nm CMOS process,the proposed amplifier is designed and verified.The simulation results show that,when driving the 10 pF capacitive loading at the supply voltage of 0.9 V,the proposed amplifier can achieve DC gain of 69.5 dB and gain-bandwidth product(GBW)of 13.3 MHz,and the power consumption is only 4.5μW.Moreover,the proposed amplifier achieves a better quality factor(FOM)in comparison with the existing solutions.

关 键 词：亚阈值共源共栅补偿 亚阈值区域 运算放大器 低压低功耗 稳定性分析 仿真验证 

分 类 号：TN722.77-34[电子电信—电路与系统]