Integrated circuit arrangement with active filter has trimmer that sets bias current of first and further transconductance stages so transconductances differ according to sum of output conductances

摘要

The integrated circuit arrangement has an active filter including transconductance stages. A trimmer sets the bias current of the first transconductance stage to achieve a desired characteristic and sets the bias current of at least one further transconductance stage so that the transconductance of the further stage(s) differs from that of the first according to the sum of output conductance values loading the transconductance stage outputs. The integrated circuit arrangement has an active filter including transconductance stages (gm1,2) that can each be adjusted with a bias current and a trimmer for trimming the filter that sets the bias currents of the transconductance stages. The trimmer sets the bias current (Itun1) of the first transconductance stage to achieve a desired characteristic for this stage and sets the bias current (0.8asteriskItun1 + Itun2) of at least one further transconductance stage so that the transconductance of the further stage(s) differs from that of the first by a value corresponding to the sum of output conductance values loading the transconductance stage outputs. AN Independent claim is also included for the following: (a) a method of trimming an active filter in an integrated circuit.