Hybrid continuous-time/discrete-time cascade σδ modulator with adaptive inter-stage resonation

A novel architecture of a hybrid continuous-time/discrete -time cascade SigmaDelta modulator that takes advantage of both circuit techniques, by including implicit anti-aliasing filtering and reduced sampling requirements, while presenting high robustness to circuit non-idealities, is presented. These circuital features are combined with programmable resonation to optimally distribute the zeros of the noise transfer function. In addition, the unity signal transfer function is implemented in all the modulator stages in order to reduce the integrator´s output swing. All these characteristics make the proposed architecture well suited to the implementation of reconfigurable A/D conversion in future generations of wireless telecom systems.