Shifting the frequency response of switched-capacitor filters by nonuniform sampling

Author

Hurst, Paul J.

Author_Institution

Dept. of Electr. Eng. & Comput. Sci., California Univ., Davis, CA, USA

Volume

38

Issue

1

fYear

1991

fDate

1/1/1991 12:00:00 AM

Firstpage

12

Lastpage

19

Abstract

A clock with nonuniformly spaced sampling times can be used to shift the frequency response of switched-capacitor filters. By using such a clock, which deviates only slightly from a uniform sampling clock, small shifts in the frequency response of a switched-capacitor filter can be realized. The nonuniform sampling generates undesired modulation sidebands which are small if the deviation from uniform sampling is small. Computer simulations and measured data are presented to support equations that predict the frequency response shift and the amplitude of the undesired sidebands. This technique can be used to correct frequency response errors in monolithic switched-capacitor filters caused by capacitor ratio inaccuracies. It may also be useful in applications such as spectrum analyzers and tone generators

Keywords

frequency response; switched capacitor filters; SC filters; active filters; capacitor ratio inaccuracies; clock; error correction; frequency response; frequency response shift; modulation sidebands; monolithic filters; nonuniform sampling; nonuniformly spaced sampling times; spectrum analyzers; switched-capacitor filters; tone generators; Clocks; Computer errors; Computer simulation; Equations; Error correction; Filters; Frequency measurement; Frequency response; Nonuniform sampling; Sampling methods;

fLanguage

English

Journal_Title

Circuits and Systems, IEEE Transactions on

Publisher

ieee

ISSN

0098-4094

Type

jour

DOI

10.1109/31.101299

Filename

101299