Abstract: Two high-performance switched-capacitor (SC) integrators which use different approaches for the compensation of the operational amplifier finite dc gain and offset voltage are considered. Analytical expressions for the gain, phase and offset voltage errors of the Baschirotto-90 integrator are derived and compared with the corresponding errors of the Shafeeu-91 integrator. Both the integrators are used as building blocks of a high-Q bandpass SC biquad. The resultant filters are compared in terms of the percent deviations from the ideal case of the central frequency and the quality factor. Subsequently, the slight shift in the frequency response of the biquad with Shafeeu-91 integrator is eliminated by modifying the values of two capacitors.
Key words: Gain compensation, offset compensation, operational amplifiers, switched-capacitor integrators, filters.