余量增益单元测试平台下高增益运算放大器设计  

Design of high gain operational amplifier on MDAC testing platform

作　　者：薄鹏 宋树祥[1] 岑明灿 BO Peng;SONG Shuxiang;CEN Mingcan(School of Electronic and Information Engineering,Guangxi Normal University,Guilin 541004,China)

机构地区：[1]广西师范大学电子与信息工程学院,广西桂林541004

出　　处：《广西大学学报(自然科学版)》2025年第1期83-93,共11页Journal of Guangxi University(Natural Science Edition)

基　　金：国家自然科学基金项目(62061005);广西自然科学基金项目(2022GXNSFBA035646)。

摘　　要：余量增益单元(MDAC)中运算放大器性能直接决定MDAC建立速度、建立精度和功耗,且随着对MDAC性能要求的提升,对运放的增益、带宽、相位裕度和功耗的要求也变得更加严格。然而,目前运放的设计及测试与应用是相对独立的,设计出的运放在实际应用中存在可靠性与准确性问题,同时针对性调整时还面临测试反馈周期长等问题。本文搭建无采样保持电荷分享型MDAC测试平台,该平台实现了运放设计、测试与应用的一体化,从而提升了运放在实际应用中的准确性和可靠性。设计了带增益提升(Gain-boost)技术的Cascode补偿两级全差分运算放大器结构,通过增益提升技术提升整体运算放大器增益,引入Cascode补偿技术提供了更高频的次级点并抵消了高频零点来保证运放稳定性。采用TSMC180 nm工艺,仿真结果显示运放开环增益为127 dB,单位增益带宽为1.733 GHz,1000次蒙特卡洛仿真下MDAC建立时间平均值为2.5 ns,建立精度平均值为101 dB,最大功耗为1.77 mA。The performance of the operational amplifier in MDAC directly determines the setup speed,accuracy,and power consumption of MDAC,and with the improvement of MDAC performance requirements,the requirements for gain,bandwidth,phase margin,and power consumption of op amps are also more stringent.At present,the design,test and application of op amp are relatively independent,which leads to the reliability and accuracy problems of the op amp in the application,and there are also problems of weak pertinence and long test feedback cycle when contrapuntally adjusting.In this paper,a sample-free charge-sharing MDAC test platform was built for the integration of design,testing,and application of the opamp,which improved the accuracy and reliability of the opamp in practical application.The two-stage fully differential opamp structure with Gain-boost technology was designed,and the overall gain of the opamp was improved by the gain boost technology,and the introduction of Cascode compensation technology provided the secondary point of higher frequency and offsets the high frequency zero point to ensure the stability of the op amp.Adopting TSMC 180 nm process,and the simulation results show that the operating loop gain is 127 dB,the unit gain bandwidth is 1.733 GHz,the average MDAC setup time under 1000 Monte Carlo simulations is 2.5 ns,the average establishment accuracy is 101dB,and the maximum power consumption is 1.77 mA.

关 键 词：增益提升技术 全差分运算放大器 蒙特卡洛仿真 余量增益单元 模数转换器 

分 类 号：TN432[电子电信—微电子学与固体电子学]