全差分可调频率四阶Chebyshev滤波器的实现  

Realization of Fully Differential Fourth-Order Chebyshev Filter with Tunable Frequency

作　　者：江金光[1] 何怡刚[1] 吴杰[1] 

机构地区：[1]湖南大学电气与信息工程学院,长沙410082

出　　处：《电子与信息学报》2004年第5期800-806,共7页Journal of Electronics & Information Technology

基　　金：国家自然科学基金(No.50277010);湖南大学撷英计划资助课题

摘　　要：提出了一种新的全差分运算放大器,该运算放大器在具有电压共模负反馈的同时还具有电流共模负反馈,能较好地稳定其工作点。通过利用MOS管工作在线性区便能作可变电阻之用的特性,设计实现了基于R-MOSFET-C运放的全差分频率连续调节的四阶Chebyshev低通滤波器。该滤波器采用台湾联电(UMC)2层多晶硅、2层金属(2P2M)5V电源电压、0.5μm CMOS工艺生产制造。其芯片面积大小为0.36mm^2,截止频率调节范围为20kHz到420kHz,输入信号频率在100kHz,2.5Vpp时的失真小于-65dB,功耗仅为16mW。A fully differential R-MOSFET-C fourth-order Chebyshev filter employing fully differential operational amplifier, passive resistors and current-steering MOS transistors is proposed, this proposed implementation relies on the tunability of current-steering MOS transistors in the triode region acting as variable resistors in order that the cutoff frequency of the filter could be tuned continuously, the amplifier is not only with voltage commonmode negative feedback, but also with current common-mode negative feedback, which will benefit for the stability of its de operating point, the filter whose cutoff frequency range is from 20kHz to 420kHz, demonstrates better than 65dB THD with 100kHz, 2.5Vpp input signal in Taiwan UMC 2P2M(2-Poly, 2-Metal) 0.5μm CMOS technology, the filter measures 0.36mm^2, and consumes only 16mW from a single 5.0V power supply.

关 键 词：全差分式 电流共模负反馈 四阶Chebyshev滤波器 低通滤波器 

分 类 号：TN713.4[电子电信—电路与系统]