A CMOS low sensitivity switched-capacitor video filter

The very low sensitivity properties of a switched-capacitor structure based on a parallel connection of two allpass filters has been recently demonstrated by computer simulations. This paper presents the IC design of a SC video filter using this technique. Initially some of the sensitivity properties are demonstrated by presenting experimental results obtained in the laboratory, using a discrete prototype filter. Then a methodology for testing the filter basic building blocks is reported. Post layout simulation results are shown, as well, to verify the IC design.