An Adaptive ELD Compensation Technique Using a Predictive Comparator

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.