Calibrated fully differential RC filter

摘要

A calibrated RC filter ( 4 ) includes a fully differential calibration circuit ( 10 ) and finite state machine ( 8 ) for determining processing variations in the resistive and capacitive components of a RC filter ( 6 ). The finite state machine controls tunable capacitors ( 7 ) in the RC filter ( 6 ) according to the results of the calibration. In order to provide a symmetrical coverage range, an asymmetrical correction code is used for the nominal case.