线性可调全差分OTA的实现  

Realization of linearly tunable fully differential OTA

作　　者：李志军[1,2] 曾以成[3] 

机构地区：[1]湘潭大学信息工程学院,湖南湘潭411105 [2]湘潭大学智能计算与信号处理教育部重点实验室,湖南湘潭411105 [3]湘潭大学光电工程系,湖南湘潭411105

出　　处：《电路与系统学报》2013年第1期102-106,112,共6页Journal of Circuits and Systems

基　　金：国家自然科学基金项目(61176032);湖南省重点学科资助项目

摘　　要：为了解决CMOS OTA跨导增益不能线性调节的问题,本文采用AB电流镜对NMOS和PMOS差分对管实现的基本OTA进行电流偏置,从而实现了一个跨导增益可以宽幅线性调节的全差分CMOS OTA电路。提出的OTA能够通过调节外部电流Iadj实现线性调节跨导增益,其误差小于2%,外部电流Iadj的调节范围为-40 A^40 A。OTA的差分输入电压摆幅为200mVp-p,输出电流的非线性度小于1.2%。电路的性能通过PSPICE仿真得到了验证。A CMOS operational trans-conductance amplifier（OTA） which trans-conductance gain can be electronically and linearly tuned is proposed in this paper.The realization method is achieved by biasing the two balanced CMOS OTAs with AB current mirror.The trans-conductance gain of the proposed OTA can be linearly adjusted through an external bias current,I adj,for two decades with less than 2% error.The linear adjusting rang of I adj is from-40 A to 40 A.The input-voltage range of about 200mV p-p with less than 1.2% nonlinearity is obtained.The performance of the proposed OTA is discussed and confirmed through PSPICE simulation results.

关 键 词：AB电流镜 跨导线性 OTA 跨导增益 线性可调 

分 类 号：TN713[电子电信—电路与系统]