[Show abstract][Hide abstract] ABSTRACT: This brief presents an adaptive excess loop delay (ELD) compensation technique for continuous-time delta-sigma modulators. This technique utilizes a predictive comparator with adaptive control using the sign least-mean-square algorithm to estimate the compensation coefficients. Contrary to other state-of-the-art compensation methods, the proposed technique is immune to manipulation of the loop filter transfer function and loop circuitry. Consequently, it will not deteriorate the performance of the modulators. Simulations performed on two different delta-sigma modulators show the effectiveness of the proposed technique to compensate the ELD in low-pass and bandpass delta-sigma modulators.
Full-text · Article · Sep 2009 · Circuits and Systems II: Express Briefs, IEEE Transactions on
[Show abstract][Hide abstract] ABSTRACT: A new excess loop delay compensation technique for continuous-time DeltaSigma-modulators by using signal interpolation is presented. This technique uses an auxiliary differentiator in the feedforward path to construct a signal interpolation at the input of the quantiser to enable an early decision that compensates for excess loop delay. A simple tuning for the interpolation coefficient makes this technique suitable for lowpass, as well as bandpass, modulators. The proposed technique enables the compensation of any amount of delay and does not impose modification on loop filter transfer function or circuitry.
No preview · Article · Jul 2009 · Electronics Letters