Exact design of switched-current ladder filters

The authors discuss the implementation of exact simulations of passive filters by switched-current techniques, using the bilinear transformation. It is shown that the synthesis can be easily done directly, without passing through an intermediary switched-capacitor filter. The realization of the input branch, which is somewhat different from the ones usually used for switched-capacitor realizations, is detailed, with various possible forms shown. Some aspects of the proposed realizations, like sensitivity, are also discussed