具有寄生极点的二阶电流模式滤波器的可调性
TUNING OF SECOND-ORDER CURRENT MODE FILTERS IN THE PRESENCE OF PARASITIC POLES
-
摘要: 积分器寄生极点离主极点不是很远时,会引起全集成滤波器参数的偏差。文中分析了积分器有限直流增益和非主极点的影响,给出了二阶滤波器极点频率和品质因数的微变公式,研究了滤波器的可调控性。在此基础上,提出了增益可调型电流模式连续时间积分器,用这种积分器实现的滤波器能实现fp和Q的双调控。Abstract: The characteristics of fully integrated filters would deviate from the desired values in the presence of parasitic poles. The effects of the finite DC gain and non-dominant poles of the integrators on filter perfomance are analyzed, deviation fomulas of pole frequency and quality factor for the second-order filters are given, and tuning of filter characteristic parameters is dealt with. Moreover, a gain-tunable current-mode continuous-time integrator is presented. Both fp and Q can be tuned with the filter based on the integrator.
-
Kozma K A, Johns D A, Sedra A S. Automatic tuning of continuous-time integrated filters using an adaptive filter technique. IEEE Trans. on CAS, 1991, 38(11): 1241-1248.[2]Kozma K A, Johns D A, Sedra A S. Tuning of continuous-time filters in the presence of parasitic poles[J].IEEE Trans. on CAS-I.1993, 40(1):13-20[3]Zele R H, Lee S S, Allstot D J. A 3V-125MHz CMOS continuous-time filter. in Proc. IEEE Symp. Circuits Syst, Chicago, IL: 1993, 1164-1167.[4]Zele R H, Allstot D J. Low-power CMOS continuous-time filters. IEEE J. of Solid-State Circuits, 1996, SC-31(2): 157-168.[5]Smith S L, Sanchez-Sinencio E. Low voltage integrators for high-frequency CMOS filters using current mode techniques. IEEE Fans. on CAS-II, 1996, 43(1): 39-47.[6]希维迪斯著,叶金官,等译.MOS晶体管的工作原理及建模.西安:西安交通大学出版社,1989,268-304.[7]Klumperink E A M, Seevinck E. MOS current gain cells with electronically variable gain and constant[8]bandwidth. IEEE J. of Solid-State Circuits. 1989, SC-24(5): 1465-1467. -
计量
- 文章访问数: 2058
- HTML全文浏览量: 112
- PDF下载量: 591
- 被引次数: 0
下载:
