The class of 1-bit Multi-Step Look-Ahead ΣΔ modulators and their applications

Abstract

The class of 1-bit Multi-Step Look-Ahead (MSLA) ΣΔ modulators is presented. They take into account current and future quantization errors improving upon the stability and noise shaping characteristics of conventional 1-bit ΣΔ modulators. The MSLA modulator system is found to be equivalent to a number of parallel conventional ΣΔ modulators sharing a multi-input 1-bit quantizer. The number of look-ahead steps along with other design parameters enable fine-tuning of performance vs. hardware complexity according to the application. The performance of MSLA modulators for various design parameter values is investigated, highlighting their advantages in a multitude of applications like digital transmitters, class-D power amplifiers and DACs.