一种带消失调电路的高线性度可变增益放大器  

A High Linearity Variable Gain Amplifier with DC Offset Cancellation

作　　者：王景帅 赵毅强[1] 叶茂 赵公元 胡凯[1] Wang Jingshuai;Zhao Yiqiang;Ye Mao;Zhao Gongyuan;Hu Kai(Tianjin Key Laboratory of Imaging and Sensing Microelectronic Technology, School of Electronic Information Engineering, Tianjin Universit)

机构地区：[1]天津大学电子信息工程学院,天津市成像与感知微电子技术重点实验室,天津300072

出　　处：《南开大学学报（自然科学版）》2018年第2期47-51,共5页Acta Scientiarum Naturalium Universitatis Nankaiensis

基　　金：国家高技术研究发展计划(2015AA042605)

摘　　要：基于0.18μm CMOS工艺,设计了1种带消失调电路的高线性度可变增益放大器,在实现增益d B线性连续可调的前提下,提高了放大器的线性度;同时,设计了1种片上滤波器型消直流失调电路,可实时抑制放大器的输出直流失调电压.后仿结果表明,在3.3 V的供电电压下,连续增益动态范围为(-21.5)-21.5 d B,-3 d B带宽为27.5 MHz,在0 d B增益下,输入1 d B压缩点为10.7 d Bm,等效输入直流失调电压标准差为1.831 m V.A high linearity variable gain amplifier（VGA） with DC offset cancellation（DCOC） is designed by 0.18 μm CMOS process. The VGA adopts two-stage in cascade based on feedback structure. It realizes continuous decibel linear gain variation, as well as achieves the high linearity characteristic. The proposed DCOC function block features an adequately low cut-off frequency and completes the challenge of integration on chip. Post-simulation results show that the VGA has a variable gain range of（-21.5）-21.5 d B, and the standard deviation of the input-referred DC offset residue is 1.831 m V. The-3 d B bandwidth（BW） is 27.5 MHz at the maximum gain. And the input P1 d B is up to 10.7 d Bm under the unity gain configuration.

关 键 词：可变增益放大器 线性度 DB线性 指数电路 消直流失调 

分 类 号：TN722[电子电信—电路与系统]