Analysis and Design of Switch Current Filters

• Main Authors: Shuenn-Yuh Lee, 李順裕
• Other Authors: Tai-Haur Kuo
• Format: Others
• Language: zh-TW
• Published: 1994
• Online Access: http://ndltd.ncl.edu.tw/handle/99573564185650356325

碩士 === 國立成功大學 === 電機工程研究所 === 82 === An efficient and relatively simple model of switched-current integrators is presented. By using the simple model, the systematic analysis and design procedure of switched-current filters are discussed. The nonidealities of switched-current( SI) circuits resulted from clock feedthrough, current mirror mismatch , and finite output impedance are analyzed and merged as a simple error model which consists of gain error and offset error. Based on the error model, the efficient and relatively simple analysis and design procedure for a complex SI filter are demonstrated. In addition, the output offset error of switched-current filters can be reduced by two proposed methods and the unstable system caused by gain error of integrators can be avoided as adding proper feedback loss. The techniques for Z- domain analysis, Z- transform calculations, and sensitivity analysis for frequency response are also included. Based on the above analysis and methods, as an example, a 5-th order Chebyshev filter is designed, verified, and fabricated. Also, the analysis and methods can be easily extended for the analysis of other switched -current systems.