Optimum design of low-pass switched-capacitor ladder filters

A general technique for realizing Bruton\´s LDI transformation in low-pass switched-capacitor ladder filters is presented, which results is switched-capacitor integrators that are insensitive to parasitic capacitances. It is shown that the correct filter response may be obtained by realizing only the stable poles of the LDI transformed network. Realization of these "stable" poles is reduced to the problem of solving a system of nonlinear equations. The design of a third-order Chebyshev low-pass filter is presented as an example.