一种4 MHz复数滤波器及其自动调谐系统的设计  

Design of a 4 MHz Complex Filter with Automatic Tuning System

作　　者：杜定坤[1] 李永明[1] 王志华[1] Tan Seeteck 

机构地区：[1]清华大学微电子学研究所,北京100084 [2]O2Micro公司,新加坡554914

出　　处：《微电子学》2006年第6期820-824,共5页Microelectronics

基　　金：国家自然科学基金资助项目(60475018;60236020);北京市科技计划项目(D0305003040111)

摘　　要：介绍了一种基于蛙跳式低通滤波器原型综合而成的复数滤波器。该电路具有较低的灵敏度,从而提高了稳定性。滤波器的自动调谐系统具有设计简单、精度易控制等特点,并可在调谐完成后关闭,减少了功耗以及与滤波器的互扰。电路采用0.18μm CMOS工艺设计,滤波器的中心频率为4 MHz,带宽为2 MHz,增益约为0 dB,可达到约53 dB的镜像抑制比,调谐精度可以控制在3%左右,功耗为7.5 mW。A complex filter synthesized from the leapfrog lowpass prototype is proposed. The filter has low sensitivity and, therefore, an improved stability. The tuning system, which is easy to design and well controlled, can be turned off on the completion of tuning, which reduces power consumption and interference with the filter. Implemented in 0. 18 μm CMOS process, the filter is centered at 4 MHz with a bandwidth of 2 MHz and a voltage gain of about 0 dB. The image rejection ratio of the filter is up to 53 dB and its tuning accuracy is about 3%. The device consumes 7.5 mW of Dower.

关 键 词：复数滤波器 有源RC滤波器 运算放大器 自动调谐系统 

分 类 号：TN713.5[电子电信—电路与系统]