| Summary: | 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.
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