A DISCRETE OPTIMIZATION METHOD OF CASCADED SWITCHED CAPACITOR FILTERS

A discrete optimization method using a noninteraction property between the different sections of cascade switched-capacitor filter is described. The optimization, realized with a reduced set of intermediate parameters characterizing each section, yields to a non minimum capacitive area structure, but which has very accurate capacitor ratios and which could be realized with minimum unit capacitors. This method may be applied to switched-current filters (aspect ratios of transistor discretization). An eighth order band-pass Cauer filter and a fifth order low-pass Cauer filter show the effectiveness of this method.