一种可编程高线性CMOS OTA的设计  

Design of a Programmable Linearized CMOS OTA

作　　者：魏镜[1] 王卫东[1] 

机构地区：[1]桂林电子科技大学信息与通信学院,广西桂林541004

出　　处：《电子器件》2011年第4期415-418,共4页Chinese Journal of Electron Devices

基　　金：广西科学研究与技术开发计划项目(0731021)

摘　　要：采用SMIC 0.18μm工艺,±0.9V电源电压,提出了一种可编程高线性全对称伪差分CMOS OTA电路。提出的伪差分输入级电路基于基本伪差分(PD)结构并采用HD3前馈技术消除三阶谐波失真,输出级采用可编程电流放大器实现。使用Cadence软件的Spectre仿真器进行电路仿真可得,G_m值三个数量级可调,-3db带宽达到779MHz。最后,设计一个双二阶OTA-C滤波器验证其正确性。Based on SMIC 0. 18μm CMOS process for a power supply of ±0.9 V, a fully balanced structure of a programmable operational transconductance amplifier with high linearity is described. The proposed circuit is based on a conventional pseudo-differential structure with a third-order harmonic distortion feedforward technique to cancel out the output 3rd harmonic component, and a programmable-gain current amplifier as output stage. The performance of the proposed circuit is confirmed through Cadence Spectre simulation results. Its transconductance gain can be linearly tuned by an external bias current for more than three decades and -3 dB bandwidth of 779 MHz. Finally, design of a biquad OTA-C filter to verify the correctness.

关 键 词：可编程运算跨导放大器 共模前馈 HD3前馈 电流放大器 

分 类 号：TN752[电子电信—电路与系统]