基于伪差分结构跨导器的Gm-C复数滤波器设计  

Design of a Gm-C complex filter based on a simple frequency tuning circuit

作　　者：钟伦贵[1,2] 杨海钢[1] 刘飞[1] 高同强[1] 程心[1,2] 

机构地区：[1]中国科学院电子学研究所,北京100190 [2]中国科学院研究生院,北京100049

出　　处：《中国科学院研究生院学报》2011年第2期235-240,共6页Journal of the Graduate School of the Chinese Academy of Sciences

基　　金：国家863高技术研究发展计划课题(2008AA010701)资助

摘　　要：提出了一种可以灵活配置共模反馈模块的伪差分结构跨导器.跨导器具有高线性度以及高输入动态范围,输入输出共模可以设置在同一电平,能方便用于滤波器级联设计.提出了一种频率控制方法,用于实现复数滤波器中心频率的自动调节.该频率调谐电路主要由基本数字电路和一个振荡器构成,与传统的锁相环结构相比,更加适合在低功耗应用场合.基于该方法,设计了一个3阶巴特沃斯Gm-C复数滤波器并采用Chrt35dg 2P4M CMOS工艺进行流片.试验结果表明,该滤波器能够达到足够的镜像抑制能力来满足IEEE802.15.4协议的要求.A pseudo differential transconductor with configurable common mode feedback block is proposed.It has high linearity and high input dynamic range,and its input and out common-mode voltage can be set at the same level.Due to its good performance,a complex filter can be easily formed by using cascade design method.A frequency control method is also presented based on a simple tuning circuit to auto-adjust the center frequency of the complex filter,which is more suitable on low power applications when compared with the traditional tuning way based on PLL（phase lock loop） architecture.The tuning circuit consists of some basic digital circuits and a simple oscillator.Based on the aforementioned techniques,a three-order Butterworth Gm-C complex filter is designed and fabricated in Chrt35dg 2P4M CMOS process.The measurement results show that it can provide sufficient imagine rejection to satisfy the requirements of IEEE802.15.4 standard.

关 键 词：复数滤波器 频率调谐 Gm-C 跨导器 

分 类 号：TN432[电子电信—微电子学与固体电子学]