Interstage network to control overload in cascaded continuous-time ΣΔ modulators

An improved interstage network suitable for avoiding overload and for increasing the signal-to-noise ratio in low-oversampling-ratio cascaded continuous-time SigmaDelta modulators is reported. Feedforward coefficients, going from the input signal to the second stage, are used to control overload without affecting the behaviour of the noise cancellation filters. Moreover, the anti-aliasing functionality is preserved. Simulation results show the utility of the proposed network in terms of the overload performance