Right-direct (BI) type wide bandpass SC ladder filter with compensation for finite amplifier gain and offset voltage

Abstract

In this paper gain- and offset-compensated (GOC) modification of a sixth-order right-direct (BI) type wide bandpass switched-capacitor (SC) ladder filter is proposed. It is based on the use of simple and fast operational amplifiers (op amps) with low but precisely known and stable dc gain A. At first, the conventional integrators in the filter are replaced with GOC integrators and the unswitched capacitors in the capacitive loops are split into two capacitors. Subsequently, the nominal op amps gain value A0 is taking into account in the capacitance sizing of some appropriately chosen capacitors. .